UNITED STATES
ENVIRONMENTAL PROTECTION
AGENCY
REGION VI11
1860 LINCOLN STREET
DENVER, COLORADO
80295
EPA 908/5-81-002
JANUARY 19S1
EPA TECHNICAL REPORT
APPENDIX to
FINDING OF NO SIGNIFICANT IMPACT
CLEAR CREEK
INTERCEPTOR PROJECT
METRO DISTRICT
COMMERCE CITY, COLORADO
PREPARED BY:
DAMES & MOORE
GOLDEN- COLO. 80401
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United States
Environmental Protection Agency
Region VIII
1860 Lincoln Street
Denver, Colorado 80295
EPA 908/5-81-002
January, 1981
TECHNICAL REPORT APPENDIX to
Finding of No Significant Impact
CLEAR CREEK INTERCEPTOR PROJECT
Metro District
Commerce City, Colorado
Prepared by:
Dames & Moore
Golden, Colorado
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DISCLAIMER
This report has been reviewed by the U.S. Environmental
Protection Agency, Region VIII, Water Division, Denver, Colorado
and is approved for publication. Mention of trade names or
commercial products does not constitute endorsement or recommen-
dation for use.
ADDITIONAL COPIES
This report is available to the public through the
National Technical Information Service, U.S. Department of
Commerce, Springfield, Virginia 22161.
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-i-
SUMMARY
EPA Region VIII contracted with Dames & Moore to prepare a study
analyzing the flow-related impacts of the Clear Creek Facilities Plan,
including both the Clear Creek Interceptor 201 plan approved by Metro
District (MDSDD) and the recently announced Golden/Coors municipal
wastewater treatment plant. Dames & Moore's studies included data
gathering activities, impact analysis, mitigation technique development
and negotiations and consultation. The study focused on the effects of
changes in Clear Creek streamflow caused by both the proposed interceptor
to the MDSDD Central Plant and the addition of a new Golden/Coors plant.
The heart of the impact analysis was a water balance on Clear Creek which
provided monthly average streamflows for present conditions and allowed
the calculation of streamflow changes for the present and year 2000
situations with the project in place. Streamflow changes were also
calculated for conditions in which the project is in place and existing
in-basin wastewater treatment plants (WWTP) operated by Clear Creek
Valley Water and Sanitation District, City of Arvada and Wheat Ridge
Sanitation District close down. Based on these results, impacts on water
rights, water quality, agricultural lands and aquatic habitat were
assessed. The study also included consideration of utilization of the
proposed interceptor corridor for recreational purposes after pipeline
construction.
FINDINGS
1. The results of the impact analysis indicated that the project
(MDSDD Clear Creek interceptor and Golden/Coors plant) will have sub-
stantial streamflow related impacts on the Clear Creek Basin. Stream-
flows will be augmented in the reach of Clear Creek between Mclntyre and
Youngfield Streets during irrigation season months. If the existing
in-basin plants remain open, a portion of the streamflow benefits will
continue all the way down to the Clear Creek and Platte River Ditch near
Pecos Street. If the in-basin plants close, increased flows due to the
Golden/Coors plant will not be enough to avoid adverse impacts on stream-
flow in the reach of Clear Creek from Marshall Street to Pecos Street.
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2. An assessment of Che aquatic habitat potential was made for Clear
Creek. Physical stream characteristics and streamflow indicate that the
reach from below Croke Canal to Youngfield Street has extremely limited
aquatic habitat potential because of channelization and lack of flow; the
reach from Youngfield Street to the Wheat Ridge WWTF has reasonable
physical streambed, riparian, and water quality characteristics for a
fishery and is essentially limited only by streamflow; and the reach
below the Wheat Ridge plant to the confluence with the South Platte is
severely degraded by urban runoff, landfill leachate and wastewater
treatment plant discharges, with a limited substrate for aquatic habitat.
3. Findings in this study indicate that the low flow value of 42.7 cfs
used in the past wasteload allocation studies is an order of magnitude
higher than typical low flow conditions at the existing and planned WWTP
discharge points, allowing adverse water quality impacts even when
currently proposed discharge requirements are met.
4. Adverse impacts resulting from streamflow losses on Clear Creek
include:
a) diversion losses to the Clear Creek and Platte River and
Colorado Agricultural Ditches during the runoff season and to the above
ditches plus Fisher Ditch during the late summer/fall irrigation season;
b) improvement in water quality for pollutants emitted by WWTP's,
such as chlorine and ammonia, in Clear Creek below the existing in-basin
plant discharges but further degradation below the Golden/Coors plant
outfall at Mclntyre Street, depending upon new in-stream water quality
and discharge standards. In the reduced flow reach below Marshall
Street, agricultural and urban runoff quality will play an increasing
role in determining in-stream water quality.
c) mixed impacts of the project on aquatic habitat and establish-
ment of fisheries. Increases in streamflow in the higher potential
(under present conditions) reach of Clear Creek above Marshall Street may
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possibly be nullified by future quality degradation. Further study of
the critical minimum flows required for fish survival in Summer and
Winter conditions is needed to assure benefits to aquatic habitat by the
Golden/Coors plant and recommended mitigation measures. Conditions in
the reach below Marshall Street may not be significantly improved
by in-basin plant closures.
d) adverse impacts on agricultural lands will occur in the Fisher,
Colorado Agricultural, and Clear Creek and Platte River ditches service
areas. While impacts on Fisher Ditch are not considered substantial
since agricultural lands served will probably urbanize anyway, impacts on
lands in the other ditches' service areas will be substantial, since some
lands will not be developed and are considered Prime Agricultural Lands.
These latter lands are the most significant remaining agricultural
lands within Clear Creek Basin.
e) impacts on potable water supplies will be mixed. While the
quantity of supply to Northglenn and, primarily, Thornton from Fisher,
Colorado Agricultural and Clear Creek and Platte River ditches will be
significantly depleted, quality of supply to Crestview Water and
Sanitation District through Kershaw Ditch, in addition to Northglenn and
Thornton, will be improved by closure of the existing in-basin plants.
RECOMMENDATIONS FOR MITIGATION
Based on the study, the following mitigation measure alternatives
have been proposed to augment streamflows, enhance water quality and
aquatic life habitat in selected stream reaches, and protect existing
irrigated agriculture in the lower Clear Creek area. One or a number of
these alternatives could be combined to best meet overall Clear Creek
needs:
a. Increasing in-basin treatment at the Golden/Coors plant of native
flows;
This would involve a cooperative agreement to treat current Metro
flows of native water at the Golden/ Coors plant.
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b. Pumping back effluent from the Metro plant to Clear Creek;
While this would protect lower Clear Creek agricultural lands,
it is unclear who would pay for this service.
c. Modify stream classifications and treatment standards;
To meet some of the higher use possibilities (drinking water,
aquatic life goals) some form of advanced waste treatment might be
necessary at both the Golden plant and the three wastewater planes.
d. Purchase in-stream flow rights;
This would be done to allow water maintained in-stream for water
quality, aquatic life, to be diverted at the lower Clear Creek
ditches.
e. Transfer municipal points of diversion to maintain water in Clear
Creek.
This would involve keeping municipal water supply diversions through
the lower Clear Creek ditches and upgrading the treatment plants on
the Creek.
In addition, findings of this study indicate that a recreational
corridor, probably a horse trail, is feasible utilizing the proposed
interceptor route in the reach from Youngfield Street to either Kipling
Street or Wadsworth Boulevard. Further, several Federal, state and local
funding sources, including EPA 201 construction grants funds, are avail-
able to construct the trail over the pipeline. However, need and support
for the trail among local governments and parks agencies must be estab-
lished. If the need is established, the City of Wheat Ridge and MOSDD
would need to negotiate an agreement on a funding mechanism, and later to
complete designs on the recreational trail and manage coordination of
trail and pipeline construction.
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TABLE OF CONTENTS
Page
SUMMARY I. i
1.0 PURPOSE AND OBJECTIVES 1-1
1.1 HISTORY 1-1
1.2 SCOPE 1-3
1.3 OBJECTIVES 1-4
1.4 REPORT STRUCTURE 1-4
2.0 EXISTING CONDITIONS 2-1
2.1 WASTEWATER TREATMENT 2-1
2.2 WATER RIGHTS 2-6
2.2.1 Diversion Facilities 2-6
2.2.2 Diversions and Use 2-11
2.2.3 Metamorphosis of Diversion Pattern 2-12
2.3 STREAMFLOWS 2-22
2.4 WATER QUALITY 2-42
2.4.1 General Consierations 2-42
2.4.2 Water Uses and Discharges 2-44
2.4.3 Water Quality Data 2-47
2.4.4 Water Quality Standards 2-55
2. 5 FISHERIES - AQUATIC HABITAT 2-57
2.5.1 Present Aquatic Inhabitants 2-57
2.5.2 Potential Aquatic Inhabitants 2-60
2.5.3 Physical Stream Characteristics 2-64
2.5.4 Chemical Stream Characteristics Specific
to Aquatic Life 2-70
2.6 AGRICULTURAL LANDS 2-72
2.7 USES FOR POTABLE WATER SUPPLY 2-80
2.8 RECREATION 2-81
3.0 ALTERNATIVES 3-1
3.1 FACILITY PLAN ALTERNATIVES 3-1
3. 2 PROPOSED ALTERNATIVE 3-1
3.3 TECHNICAL REPORT/FNSI ALTERNATIVE 3-2
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TABLE OF CONTENTS (Continued)
Page
4.0 IMPACTS 4-1
4.1 WASTEWATER TREATMENT 4-1
4.1.1 Facilities 4-1
4.1.2 Fate of In-Basin Municipal Plants 4-1
4.1.3 Reuse of MDSDD Central Plant Effluent 4-3
4.2 DIVERSIONS AND WATER RIGHTS 4-3
4.2.1 Diversion Records 4-3
4.2.2 Operations Study Parameters 4-4
4.2.3 Impacts Summary 4-7
4.3 STREAMFLOWS 4-8
4.3.1 Methodology 4-8
4.3.2 Winter Streamflow 4-12
4.3.3 Late Irrigation Season Streamflow 4-12
4.3.4 Runoff Season Streamflow 4-13
4.4 WATER QUALITY IMPACTS 4-20
4.4.1 General Considerations 4-20
4.4.2 Issues Not Specific to the Chosen Alternative... 4-20
4.4.3 Issues Specific to the Chosen Alternative 4-22
4.5 AQUATIC/FISHERIES 4-27
4.5.1 Possible Areas of Habitat Loss -
Short/Long Term 4-27
4.5.2 Future Importance of the Fishery 4-28
4.5.3 Impacts Resulting from Specific Alternative 4-28
4.6 AGRICULTURAL LANDS 4-31
4.6.1 Summary of Impacts 4-31
4.6.2 Slough Association 4-32
4.6.3 Fisher Ditch 4-33
4.6.4 Clear Creek and Platte River Ditch (CCPRD) 4-35
4.6.5 Colorado Agricultural Ditch 4-36
4.7 POTABLE WATER SUPPLIES 4-36
4.8 RECREATION 4-37
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TABLE OF CONTENTS (Continued)
Page
5.0 MITIGATION MEASURES 5-1
5.1 OBJECTIVES 5-1
5.2 STRATEGIES 5-1
6.0 REFERENCES 6-1
APPENDIX A
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LIST OF TABLES
Page
2-1 Existing Wastewater Discharges - 1979 Quality 2-4
2-2 Cotter Corporation, Schwartzwalder Mine, Effluent
Discharge Quality - 1979 2-5
2-3 Clear Creek Ditch, Municipal and Major Industrial
Ownership 2-14
2-4 Clear Creek Flows - January 1977 2-25
2-5 Clear Creek Flows - September 1977 2-28
2-6 Clear Creek Return Flow - Irrigation Year 1977 2-35
2-7 Clear Creek Diversions - Irrigation Year 1977 2-36
2-8 Clear Creek Gages - Irrigation Year 1977 2-37
2-9 Clear Creek Diversions - Irrigation Year 1975 2-41
2-10 Clear Creek Gages - Irrigation Year 1975 2-41
2-11 Annual Flows Pre- and Post-1967 2-43
2-12 Water Quality Data; Selected Averages -
Fecal Coliform 2-48
2-13 Water Quality Data; Selected Averages -
Ammonia (Total) 2-49
2-14 Water Quality Data; Selected Averages -
Phosphorus (Total) 2-50
2-15 Water Quality Data; Selected Averages -
Iron (Total) 2-51
2-16 Water Quality Data; Selected Averages -
Zinc (Total) 2-52
2-17 Water Quality Data; Selected Averages -
Copper (Total) 2-53
2-18 Water Quality Data; Selected Averages -
Manganese 2-54
2-19 Existing Water Quality Standards - Clear Creek 2-56
2-20 Results of Fishery Surveys in Clear Creek
Between Golden and South Platte River 2-58
2-21 Relative Abundance of Macro-Intertebrates
Collected from Clear Creek Below Golden 2-61
2-22 Fish Species Collected from Streams near
Clear Creek in the Early 1900s 2-62
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LIST OF TABLES (Continued)
Page
4-1 Effects of Project on Water Rights 4-9
4-2 Annual Changes in Flow on Clear Creek with MDSDD
Interceptor and Golden/Coors Plant 4-11
4-3 Estimated Changes in Stream Flow from Existing
Conditions (for Month of September) 4-18
4-4 Estimated Change in Diversions for Month of September 4-19
4-5 Proposed Water Quality Standards; Colorado
Department of Health; Clear Creek 4-24
4-6 Proposed Water Quality Standards; Adolph Coors
Company; Clear Creek 4-25
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LIST OF FIGURES
Page
1-1 Basin Locator Map 1-2
2-1 Point Discharges, Sampling, and Gaging Points 2-2
2-2 Diversions and Return Flows 2-7
2-3 Clear Creek Flows - January 1977 2-31
2-4 Clear Creek Flows - September 1977
Existing Conditions (1) 2-32
2-5 Clear Creek Flows - August 1977 2-33
2-6 Clear Creek Flows - May 1977 2-34
2-7 Existing Non-Point Source Discharges 2-4S
2-8 Agricultural Lands and Irrigation Ditch Service Areas 2-73
2-9 Agricultural Service Areas Below Standley Reservoir 2-75
2-10 Agricultural Service Areas - Clear Creek and Platte
River and Colorado Agricultural Ditches 2-76
2-11 Jurisdictional Boundaries, Conservation Areas,
and Floodplalns 2-78
2-12 Major Planned and Existing Recreation Features 2-82
4-1 Clear Creek Flows - September'1977 (Condition No. 2) 4-14
4-2 Clear Creek Flows - September 1977 (Condition No. 3) 4-15
4-3 Clear Creek Flows - September 2000 (Condition No. 4) 4-16
4-4 Clear Creek Flows - September 2000 (Condition No. 5) 4-17
4-5 Affected Agricultural Lands - Fisher Ditch Service Area.... 4-34a&b
(two figures)
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1-1
1.0 PURPOSE AND OBJECTIVES
1.1 HISTORY
The planning process leading to this study began in 1974 when
CH2M Hill conducted water quality studies in Clear Creek Basin at the
request of the Denver Regional Council of Governments (DRCOG). These
studies recommended construction of a satellite treatment plant on Clear
Creek. Such a plant would augment in-stream flows for downstream use,
and help maintain water quality. The Clean Water Plan published by DRCOG
in 1977 reaffirmed this position by recommending the satellite facility,
but noted possible difficulties in attaining stream quality sufficient to
maintain desired uses.
In August 1977, the Metropolitan Denver Sewage Disposal District No.
1 (MDSDD) completed a facility plan for the Clear Creek Basin as required
i
under Section 201 of the Clean Water Act. This plan considered two basic
approaches for handling the increasing wastewater flows in the basin.
One was construction of a satellite plant on Clear Creek, as recommended
by the DRCOG studies. The other was expansion of the existing inter-
ceptor system which conveys flows from the Clear Creek basin to the MDSDD
Central Plant in Commerce City. The Facilities Plan concluded that cost
effectiveness considerations strongly favored the expanded interceptor
plan, and this was thus designated as the proposed alternative (CH2M
Hill, 1977). The Clear Creek Basin, which constitutes the Facility Plan
area, is shown on the locator map in Figure 1-1.
EPA prepared an "Overview" Environmental Impact Statement (EIS) for
ten Denver Metropolitan Area 201 planning studies including Clear Creek
in 1978. The final action document associated with the EIS defined the
following special condition for Clear Creek:
"EPA prefers that a sub-regional facility be constructed
in the Clear Creek Basin below Golden and Coors which
would serve to maintain in-stream water quality and
flows. Additional study is necessary through the Clean
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1-3
Water Plan and facility planning to resolve any con-
flicts. EPA will reserve judgment on whether the re-
mainder of the basin should receive treatment at the
Metro facility until such time as the State decides upon
the Clean Water Plan's proposed classification for Clear
Creek and further analysis is made to determine the
feasibility of discharging effluent from these facilities
to Clear Creek or to downstream irrigation ditches on a
full or part time basis."
DRCOG reversed its former position in March 1979 by voting to
approve the interceptor alternative for the Clear Creek Basin. In
addition, several municipalities announced plans to alter their use of
Clear Creek flows, and other new circumstances arose subsequent to
Facility Plan completion. Most recently, the City of Golden and the
Adolph Coors Company signed an agreement under which Coors would treat
their combined municipal wastewater flow at a locally-funded treatment
plant below Golden.
As a result, EPA determined that a re-analysis of overall impact of
the combined interceptor and Golden/Coors plant was necessary to comply
with National Environmental Policy Act provisions relating to the 201
Facility Plan. EPA subsequently contracted with Dames & Moore to conduct
such a study, the results of which are reported herein.
1.2 SCOPE
During this study, Daiaes & Moore conducted data gathering, impact
analysis, mitigation technique development, and negotiation and consulta-
tion work. Field work was limited to a brief reconnaissance along the
creek and field checking of agricultural lands, with all other analysis
being based on existing information and direct contacts with pertinent
parties. Flow impact studies conducted in the facilities plan and a
supplementary study (Leonard Rice, 1978) were extended to account for
effects of new in-basin treatment facilities under the Golden/Coors
proposal. Environmental impact studies concentrated on assessing
the effects of the proposed interceptor expansion and Golden/Coors
plant on stream flows, water quality/use, water rights, aquatic habitat/
fisheries, agricultural lands, and recreation.
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1-4
1.3 OBJECTIVES
The studies reported herein were designed to provide EPA with the
information to evaluate the impacts on the Clear Creek Basin from the
MDSDD proposal given EPA's position on the "Overview" EIS and with the
recentl/ proposed wastewater treatment plant changes. EPA tentatively
expects to issue a Finding of No Significant Impact (FNSI) for the Clear
Creek Facility Plan at this point in time.
1.4 REPORT STRUCTURE
This technical report independently evaluates the Impact of the
MDSDD proposal on Clear Creek Basin and will serve as a support document
for the FNSI. Support information contained herein is incorporated in
the FNSI by reference. Readers desiring further detail on any determina-
tions or impact assessments presented in the FNSI will find this report
serves that need. Descriptions of some of the more complex methodologies
used in this study have been appended in the interest of keeping the text
more readable.
Sections 2 and 4, the existing conditions and impacts discussions
respectively, are organized by the major study issues with parallel
subheadings to facilitate comparisons. The general methodology employed
involves analysis of streamflows and related or affected aspects of the
local environment. The basis of the discussions is an analysis of
existing gauged streamflows, diversion patterns, water uses, return
flows, and wastewater discharges, to yield estimates of average monthly
streamflow along Clear Creek from the U.S.G.S. gauge above Golden to the
mouth. These estimates have been completed for past, present, and future
conditions to identify the effects of the existing interceptor and the
proposed project and to allow assessments of impacts on water quality,
agriculture, aquatic habitat and fisheries, and water rights.
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2.0 EXISTING CONDITIONS
In this section, data are presented which allow the analysis of
flow-related impacts in Section 4.0. Also, information is presented
which allows the analysis of opportunities for enhancement of recre-
ational use of the Clear Creek corridor by use of the interceptor route.
Sections 2.0 and 4.0 are organized in parallel to facilitate comparison
of the existing environment with the future project affected environment
of the Clear Creek Basin. The basin is illustrated in relation to the
rest of the State of Colorado in Figure 1-1.
2.1 WASTEWATER TREATMENT
A profile of existing methods of wastewater disposal for the
Clear Creek Basin is provided in this section to aid in the under-
standing of existing Clear Creek water quality problems (Section 2.4) and
the effects of the chosen alternative (Section 3.0) on wastewater treat-
ment methods and future water quality.
The existing wastewater treatment facilities and discharge points in
the Clear Creek Basin are shown in Figure 2-1. The Clear Creek Inter-
ceptor shown is actually the chosen plan, but follows roughly the same
route as the existing interceptor to the MDSDD Central Plant, where most
of the municipal wastewater treatment for the basin is provided. Other
municipal facilities presently operating in the basin include plants
operated by Wheat Ridge Sanitation District, City of Arvada, Clear Creek
Valley Water and Sanitation District, and Northwest Lakewood Sanitation
District. All except Clear Creek Valley are members of the MDSDD and
contribute additional wastewater flows to the existing interceptor and
central plant. The Northwest Lakewood plant discharges all wastewaters
to the interceptor. The Arvada plant discharges to Ralston Creek just
above its mouth.
One major industrial discharger, Adolph Coors Company, operates
facilities in the basin. It should be noted that Coors employs two
process wastewater discharge points. During winter months, roughly
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2-3
November through March, effluent is discharged to Croke Canal, which
diverts from the north bank of Clear Creek about tvo-thirds miles east of
the plant (Jaquet, 1980). The remainder of the year, effluent is dis-
charged to Clear Creek about 300 yards east of Mclntyre Street. In
addition to process wastewater, Coors discharges non-contact cooling
water to Clear Creek at several points near its main plant. Other
industrial type dischargers in the basin are Cotter Corporation's
Schwartzwalder Mine, Public Service Company's (PSC) Leyden gas storage
facilities, and Western Paving Company. Leyden PSC involves well pumping
into ponds which seldom discharge to surface waters. Cotter Corporation
discharges mine water to Ralston Creek above Ralston Reservoir. Western
Paving has a very small discharge from its asphalt plant at 64th and
Pecos.
Table 2-1 shows the type of treatment, NPDES permit limitations,
and effluent flow and quality in 1979 for the major municipal and
industrial dischargers. In addition to those discharges listed in Table
2-1, Cotter Corporation Schwartzwalder Mine has limitations and discharge
parameters listed in Table 2-2.
The municipal plants are achieving marginal secondary treatment.
The Arvada and Wheat Ridge plants are trickling filter type and have
trouble meeting BOD and TSS limitations during the cold weather months.
The Arvada, Wheat Ridge, and Clear Creek Valley plants have all had
trouble meeting fecal coliform and residual chlorine requirements
(Woodling, in preparation) although Clear Creek Valley had no violations
during 1979. The MDSDD Central Plant discharges to the South Platte
River rather than Clear Creek, as shown in Figure 2-1, and effectively
provides secondary effluent quality. The Crestview Water and Sanitation
District plant is shown in Table 2-1, since it contributed pollutants and
stream flow to the lower part of the basin in the recent past.
Data for Coors in Table 2-1 show that there are different permit
limits for BOD, TSS, and Total Residual Chlorine when discharge is to
Croke Canal rather than Clear Creek. Limits for discharge to Clear Creek
are in Table 2-1; limits for discharge to Croke Canal are as follows:
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TAIiI.E 2-1
EXISTING
WASTEWATER DISCHARGES
1979 QUALITY
(1)
PI ant/Discharger
Arvada
Wheat Ridge
Clear Creek Valley
Northwest Lakewood
MDSDD Central
Coors
Crestview
Type of
Treatment
Trickling
Filter
Trickling
Filter
Activated
Sludge
Primary
Activated
Sludge
Activated
Sludge
Trickling
Filter
Flow
MOD
0.82
(0.9 CAP)
1.57
(2.5 CAP)
1.85
(2.1 CAP)
2.2
(2.2 CAP)
24-147 (3>
(170 CAP)
3.20
(6.5 CAP) W
0.8
(1.0 CAP)
BOD
mg /I
Effluent
TSS
mg/1
19.1 ( 27.8
(30/45r ' (30/45)
30.9
(30/45)
12.8
(30/45)
25.5
(30/45)
16.2
(30/45)
DISCHARGE PRIMARY
Quality (NPDES Limit)
F.COLI
///100ml
190
(1000/2000)
1178
(3000/6000)
1001
(1000/2000)
EFFLUENT TO
C12
mg/1
0.41
(0.5)
0.45
(0.5)
0.48
(0.5)
NH3
mg/lasN
16.4
11.9
( - )
_
( - )
MDSDD INTERCEPTOR
19
(20/30)
12.3
20(Daily
19
(20/30)
560<5>
Avg) (2650/3975)
LAST OPERATED IN
271
(1000/2000)
236
(1000/2000)
1977
0.5 ,,,
d.5)(6)
0.48
(0.05)^'
(- )
1.18
(3.0)
(1) a-b Indicates Avg. to Maximum Monthly Quality Data, Unless Noted Otherwide
(2) (c/d) Indicates Monthly and Weekly Averages (6) Max. 2-Hour Sample
(3) e-f Indicates Clear Creek Interceptor and Total MDSDD Plant Flow
.(4) BOD and C12 LJmits for Discharge to Clear Creek (5) Ib/day TSS; (Daily Avg./Instantaneous)
to
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TABLE 2-2
Cotter Corporation
Schwartzwalder Mine
Effluent Discharge Quality - 1979
(1)
Permit Limits
Effluent Quality
Flow, MGD
BOD
TSS
Tot. Iron
Tot. Manganese
Tot . Uranium
Tot. Lead
Tot . Zinc
Tot . Barium
Tot. Cadmium
Tot. Arsenic
Oil & Grease
Radium, pCi/1
Fecal Coliform(2)
#/100ml
Avg.
-
10
20
0.5
0.05
3.0
0.05
0.5
1.0
1.0
0.05
-
3
1000
Max.
-
15
30
1.0
0.1
5.0
0.1
1.0
2.0
2.0
0.1
10
10
2000
Average
0.56
11
14
0.74
0.07
2.18
0.04
0.02
0.11
0.01
0.01
0
2.2
40
(1)
(2)
All in mg/1 except as noted
Permit limits are 30-day avg. & 7-day avg.
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Mass Limits, Ib/day Concentration Limits, mg/1
BOD 2650/3975 30/45
(Daily max./Inst.) (30-day avg./7-day avg.)
C17 0.5 (maximum)
One new plant is now being constructed in the basin by Coors. This
will be a new process WWTP, located less than 1 mile east of the existing
plant, and discharging at the same two points as the existing plant.
This plant will be sized for an average flow of about 6.0 MGD (Holmer,
1980); based on projections of production, the plant will be at or
slightly above this level in the year 2000 (Jaquet, 1980). Information
on treatment requirements for this plant are not available to date, and
will depend on the final content of revisions to the Colorado water
quality standards now under consideration (see Section 4.4).
2.2 WATER RIGHTS
2.2.1 Diversion Facilities
Between the Welch Ditch headgate, which is located one mile upstream
of the Clear Creek near Golden U.S.G.S. gaging station, and the con-
fluence of Clear Creek and the South Platte River, there have his-
torically been approximately 24 headgates through which stream flows have
been diverted. The general alignment and location of the ditches and
headgates are shown on Figure 2-2.
Each of the ditches has its own unique characteristics which
make it different from any other ditch on the stream. The Welch Ditch
and the Agricultural Ditch are both administered by the Agricultural
Ditch and Reservoir Company (Neill, 1980). In addition to using the
direct flow water associated with each of the two ditch headgates, the
ditch company receives water from several reservoirs which are located
further upstream. These reservoirs are Loch Lomond, Lake Carolyn, Twin
Lakes, Ice Lake, Ohman Lake, Chinns Lake, Upper Chirms Lake, and Wild
River Reservoir (Consolidated case No.'s W-8036(75) and W-8256(76),
1977).
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2-8
Diversions of the Church Ditch and the City of Golden are taken out
of the Church Ditch headgate, however, City of Golden water is separated
from the Church Ditch water almost immediately downstream. The Church
Ditch is a carrier ditch now owned by the City of Northglenn. In addi-
tion to supplying water to agricultural users, the ditch structure is
used by various municipalities for delivering water to Standley
Reservoir. The ditcn officially ends near 100th and Simms at what is
called the Ketner Weir. Downstream of the Ketner Weir is the Dry Creek
Valley Ditch which is entitled to receive 58% of the Church Ditch water
(Vukelich, 1980). At the point where the Dry Creek Valley Ditch crosses
Walnut Creek there is a take out for another ditch called the Equity
Ditch. The Equity Ditch is entitled to 11.6 % of the Church Ditch water.
The 11.6% is included in the 58% allocated to Dry Creek Valley Ditch.
The Dry Creek Valley Ditch eventually empties into the Community Ditch,
which is part of Farmer's Reservoir and Irrigation Company's (FRICO)
Marshall Division. The Community Ditch is entitled to 8% of the water
diverted at the Church Ditch headgate (Sauer, 1980).
The Farmers Highline Canal is officially organized as the Farmers
Highline Canal and Reservoir Company. Reservoirs owned by the company
are Leyden Reservoir and Hiatt Reservoir. In addition, there are approx-
imately 80 small individually-owned reservoirs or holding ponds which are
used to store fluctuating flows received from the canal for future use.
This canal is also unusual in that, even though it is a mutual ditch
company, some of the water rights that are decreed at the canal's head-
gate are not owned by all the shareholders within the company. Some of
the water was given out to ownership under schedule rights, and some of
the water is what is called contract water. Contract water is served to
a small area in the upper part of the system in which the water rights
are attached to the land as part of the water rights decrees. These
priorities of the contract water are senior so that lands associated with
these rights always have a good water supply. Schedule rights are also
attached to specific parcels of land, but share equally in the water
diverted in association with the ditch company's headgate decree with
the rest of the ditch and reservoir company, up to a cutoff date. This
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2-9
canal also has the ability to deliver water to Standley Reservoir
(Anderson, 1975; Dirrim, 1980).
The Croke Canal is the official feeder ditch for Standley Reservoir.
Both facilities are owned by TRICO. There is no irrigation at all
between Clear Creek and Standley Reservoir, so all of the water that Is
delivered or diverted by the Croke Canal is delivered to lands which lie
outside the Clear Creek basin. These lands are all in the Dry Creek
Basin north of Clear Creek (Zeigler, 1980; Bolander, 1980).
The Coors Industries Ditch, Wannamaker Ditch, Rocky Mountain
Ditch, Miles and Eskin's Ditch, Lee, Stewart and Eskin's Ditch, and
South Side Ditch are all associated with the Adolph Coors Company,
although Wannamaker Ditch and Lee, Stewart and Eskin's Ditch have other
shareholders who use water for agricultural and municipal purposes. The
Coors Industries Ditch is used for diverting cooling water only. The
Rocky Mountain Ditch, Wannamaker Ditch and Miles and Eskin's Ditch
structures are used by Coors to fill its Jefferson Storage System. The
Jefferson Storage System is made up of several gravel pits which lie
downstream of the Coors plant. Water is diverted into the reservoir
system under their own junior decree or the 1962 decree for the Coors
Industries Ditch or by exchange. The exchange is discussed in Section
2.2.3. The Miles and Eskin's water right has been transfered to the
Rocky Mountain Ditch headgate by Coors and is used to irrigate the
Applewood Gold Course. The South Side Ditch is used for replacement
water only. Coors is the operator of the Lee, Stewart and Eskins Ditch,
however, this ditch is not put to any special use as are the others
associated with Coors (Griggs, 1980; Jaquet, 1980).
The Reno and Juchem Ditch is officially organized as the
Consolidated Juchem Ditch Company. This ditch company is similar
to the Farmers Highline, at least according to the City of Arvada,
in that all of the water rights associated with the headgate are not
shared equally by all of the shareholders. Shareholders of the
Consolidated Juchem Ditch Company, other than the City of Arvada, feel
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2-10
that all of Che rights are owned in common by all shareholders (Sullivan,
1980).
The Slough Association is not really an association at all; rather,
it is a carrier ditch for several ditch companies. There are 20 ditches
diverting water from the main Slough Ditch. All of these ditches are
fairly small and to some degree unorganized. This association has been
administered, for many years, as one entity. However, in 1978, the State
Engineer started monitoring the amount of water that was diverted by each
ditch individually (Rock, 1980; Anderson, 1980).
The Cort, Graves and Hughes Ditch, Boyles Ditch, Oulette Ditch and
Kershaw Ditch are all small ditches with just a few water users. The
Kershaw Ditch, along with the Manhart Ditch on Ralston Creek provides
water for the Crestview Water and Sanitation District (Spano, 1980;
Boyce, 1980; Heckers, 1980).
The Fisher Ditch Company is another ditch company that diverts
water not only for itself but for another company. The ditch officially
ends at Copeland Lake located just east of 1-25. At this point, United
Water Company takes over administration of Fisher Ditch water and
is entitled to 44.9% of the water diverted at the Fisher Ditch headgate.
United Water Company also picks up the tail water from the north branch
of the Rocky Mountain Ditch at Dewey Lake. However, United Water Company
is not officially entitled to any share of the Rocky Mountain Ditch
water (Firole, 1980; Gaccetta, 1980).
The Colorado Agricultural Ditch Company and the Clear Creek and
Platte River Ditch Company both take water through the same headgate.
However, shortly downstream the Colorado Agricultural Ditch takes off
from the Clear Creek and Platte River Ditch. The ditches closely
parallel each other and serve approximately the same lands (Rullo, 1980;
Fukaye, 1980).
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2-11
The Welch Ditch, Agricultural Ditch, Church Ditch, Farmers Highline
Canal, Rocky Mountain Ditch, Fisher Ditch, Colorado Agricultural Ditch,
and the Clear Creek and Platte River Ditch all deliver water to lands
which lie both within and outside the Clear Creek Basin boundaries. The
Croke Canal delivers water to lands which lie outside Clear Creek Basin
exclusively. The rest of the active ditches deliver water to lands which
lie ccnpletely within Clear Creek basin boundaries. The Lee's Island
Ditch, John S. Risdon Ditch, John S. Risdon Seepage Ditch, Ramboz No. 3
Ditch, and Page Ditch, which have been identified in past studies, are no
longer active (Anderson, 1980).'
The only major municipal or industrial user which has any wells
located in the Clear Creek alluvium is the Adolph Coors Company. Coors
has approximately 49 alluvial wells located in the stretch of Clear Creek
between the upstream end of the Coors plant and the point where Clear
Creek crosses underneath Interstate 70 at Youngfield. There are plans to
locate another 23 wells in this same stretch of streambed. All of the
present and future wells are covered in the Coors plan of augmentation
(Consolidated Case No.'s W-8036(75) and W-8256(76), 1977).
2.2.2 Diversions and Use
In the State of Colorado the distribution of water is governed
by the "prior appropriation" doctrine. This doctrine states that the
first diverter of water in a stream system has a prior or "senior"
right to the use of water, during periods of scarcity, over later
diverters. Thus, in any given stream system, water rights are rated
according to their priority or order of first use. When a water user
with a more senior priority is not receiving its full allocated water
supply as a result of another diverter further upstream with a more
junior priority diverting the available water, the senior diverter will
"call" for his allocated share. When this happens the junior appropria-
tor is legally obligated to pass the amount of water called for down-
stream to the senior appropriator. The call that is being exercised on
the stream at any given time is usually referred to by the name of the
structure for which the water is being called and the point in time when
the water right associated with the structure was first used.
-------
2-12
In the Clear Creek Basin, there is one call or another on the
stream throughout most of the year. During the winter time, the Croke
Canal puts its 1902 call on the creek and dries up the creek at its
headgate. During the early spring runoff, the call on the lower end of
Clear Creek is usually junior to the 1902 Croke call and originates from
a diverter on the mainstream South Flatte River. Near the end of June,
the Farmers Highline Canal normally calls for its 1872 water. From the
end of June to early August, the calls rapidly progress through the Welch
71, Colorado Agricultural 67, Colorado Agricultural 63, Fisher 61 and
Clear Creek and Platte River 61 call. The Fisher 61 and Clear Creek and
Platte River 61 calls are normally on the river during the months of
August, September, and October. During these months there is an unusual
situation on Clear Creek in that the calls of various structures on the
stream become more senior as one progresses upstream. The call emanating
from the Rocky Mountain Ditch (Miles and Eskins 6-11-1861 right) is
senior to that of the Fisher Ditch (6-29-1861 right) which is in turn
senior to that of the Clear Creek and Platte River Ditch (11-1-1861
right).
As a result, during this time period, the creek is dried up at the
Rocky Mountain Ditch headgate, the Slough Association headgate, the
Fisher Ditch headgate and the Clear Creek and Platte River headgate. The
Slough Association has some 1860 rights which allow it to call out more
senior rights such as those owned by the Rocky Mountain Ditch Company.
However, since there is enough return flow between the Rocky Mountain and
the Slough to satisfy the Slough, it does not need to do so. This
phenomenon occurs at other points along the stream such as at the Oulette
Ditch, Cort, Graves and Hughes Ditch and Kershaw Ditch headgates. During
the dryer years, the calls become more senior and the senior calls appear
earlier (Anderson, 1980).
2.2.3 Metamorphosis of Diversion Pattern
In the late 1800's, agriculture and grazing were established
over large areas of the plains and lower portions of the Clear Creek
basin. Irrigation canals were constructed to deliver water to thousands
-------
2-13
of acres of irrigated farm land. Following the second World War in the
early 50's, urbanization, rapidly expanded and was accompanied by some
industrialization. But urbanization and industrialization today heavily
impact the lower basin as Golden, Arvada, Northglenn, Westminster,
Thornton and the other western suburbs of Denver continue to grow and
expand. This has a direct effect on the water rights in Clear Creek
basin in that many of the land's that were once irrigated are taken out of
agricultural production and many of the water rights that were once used
for irrigation have been purchased by municipal and industrial users
(Sullivan, 1980).
One can see by examining Table 2-3 that very few of the ditches
within the Clear Creek basin have been untouched by municipal and
industrial interests. According to this exhibit, almost all of the
ditches are anywhere from 30 to 100% owned by either municipal or
industrial entities. The only major ditch that has remained unaffected
is the Welch Ditch.
Before any of the municipal and industrial users are able to
change the point of use and type of use from what has historically
been associated with their share of the Clear Creek ditches they must
demonstrate to all objectors and the Water Courts that such a change in
point and type of use will not cause any adverse impact on other water
rights that depend on Clear Creek waters as a source of supply. In order
to eliminate adverse impacts, all water transfers include a clause which
limits future beneficial use to that which has been associated with the
rights historically. In addition, the entities are required to make up
return flows that resulted from historical irrigation practices in
quantity, place and time that they historically occured. The vehicle
used for assuring that such make up water is available is normally called
a plan for augmentation. Coors and Westminster already have plans
of augmentation approved for most of their interest in the Clear Creek
while Arvada, Northglenn and Thornton are in the process of obtaining
that approval. The proposed uses and plans are described below.
-------
2-14
TABLE NO. 2-3
CLEAR CREEK DITCHES
MUNICIPAL AND MAJOR
INDUSTRIAL OWNERSHIP
(percent)
Golden1
2
Arvada
Westminster
A
Northglenn
Thornton
Broomfield
Wheat Ridge
Consolidated
Mutual ^
Crestview
W&S8
Adams County
Subtotal
9
Coors
PSCo10
Subtotal
TOTAL
Welch
0
0
0
0
0
0
0
2.5
0
0
2.5
0
0
0
2.5
Church
1.1
Negligible
9.8
7.3
0.311
29.4
0
0
0
_0
47.9
2.23
0
2.23
50.13
City of Golden
100
o'
0
0
0
0
0
0
0
0
0
0
0
0
100
Agricultural
0
0
0
0
0
0
0
33.9
0
_0
33.9
12.9
0
12.9
46.8
-------
2-15
TABLE NO. 2-3
'(Continued)
CLEAR CREEK DITCHES
MUNICIPAL AND MAJOR
INDUSTRIAL OWNERSHIP - CONTINUED
(percent)
Coors
Industries
Golden
Arvada
Westminster
Northglenn
Thornton
Broomfield
Wheat Ridge
Consolidated
Mutual
Crestview
W&S
Adams County
Subtotal
Coors
PSCo
Subtotal
TOTAL
0
0
0
0
0
0
0
0
0
0.
0
100
0
100
100
Farmers
Highline
0
4.0
25. 412
0.7
10. 711
0
0
0
0
_o
40.8
1.9
0
1.9
42.7
Wannamaker
0
0
0
0
0
0
0
0
0
2
0
56.7
0
56.7
56.7
Lee, Stewart
and Eskins Croke
0
0
0
0
0
0
0
50.2
0
0
50.2
19.4
0
19.4
69.6
0
0
1
J31.0
0
0
0
0
2
0
0
0
0
31.0
-------
2-L6
TABLE NO. 2-3
(Continued)
CLEAR CREEK DITCHES
MUNICIPAL AND MAJOR
INDUSTRIAL OWNERSHIP - CONTINUED
(percent)
Golden
Arvada
Westminster
Northglenn
Thornton
Broomfield
Wheat Ridge
Consolidated
Mutual
Crestview
w&s
Adams County
Subtotal
Coors
PSCo
Subtotal
TOTAL
Rocky
Mountain
" 0
0
0
0
0
0
0
0.6
0
0
0.6
71.4
0
71.4
72.0
Miles &
Eskins
0
0
0
0
0
0
0
0
0
0
0
100
0
100
100 -
Reno &
Juchem
0
37.1
0
0
0
0
0
0
0
0
37.1
8.8
0_
8.8
45.9
Slough
Association
0
12.5
0
0
0
0
0
0
0
0
12.5
14.3
0
14.3
26.8
-------
2-17
TABLE NO. 2-3
(Continued)
CLEAR CREEK DITCH]
MUNICIPAL AND MAJI
INDUSTRIAL OWNERSHIP - (
(percent)
Golden
Arvada
Westminster
Northglenn
Thornton
Broomfield
Wheat Ridge
Consolidated
Mutual
Crestview
W&S
Adams County
Subtotal
Coors
PSCo
Subtotal
TOTAL
Oulette
0
0
0
0
0
0
33.3
0
0
0
33.3
0
0
0
33.3
South side
0
0
0
0
0
0
0
0
0
C_
0
100
0
100
100
Cort, Graves &
Hughes
0
1.8
0
0
0
0
0
0
0
1.8
0
0
0
1.8
Boyles
0
0
0
0
0
0
0
0
0_
0
0
0.
0_
0
-------
2-18
TABLE NO. 2-3
(Continued)
CLEAR CREEK DITCHES
MUNICIPAL AND MAJOR
INDUSTRIAL OWNERSHIP - CONTINUED
(percent)
Colorado
Golden
Arvada
Westminster
Northglenn
Thornton
Br cornfield
Wheat Ridge
Consolidated
Mutual
Crestview
W&S
Adams County
Subtotal
Coors
PSCo
Subtotal
TOTAL
Kershaw
0
0
0
0
0
0
0
0
38.0
0
38.0
0
0
0
38.0
Fisher
0
0
0
0
9.410
0
0
0
\
0
0
9.4
0
19.4
19.4
28.8
Agricultural
0
0
0
0
20.814
0
0
0
0
0
20.8
0
0
0
20.8
Clear Creek
& Platte River
0
0
0
4.2
29.2
0
0
14
0
4.2
37.6
0
0
0
37.6
-------
2-19
TABLE NO. 2-3
(Concluded)
FOOTNOTES
L(Case No. 79CW236, 1980)
2(Sullivan, 1980)
3(Case No. W-8743-77, 1980)
4
(U. S. Environmental Protection Agency, 1980)
5(Sauer, 1980)
6(Heckers, 1980)
7(Case No. 79CW236, 1980)
8(Boyce, 1980)
(Case No. W-7690-74, 1975)(Consolidated Cases
Nos.,W-8036(75) and
W-8256(76), 1977)
10(Firole, 1980)
(Denver Water Department, 1976 pp. 56-59)
Westminster owns 100% of priorities #1 and 7/48
13(Bolander, 1980)
I4(Fukay, 1980); (Rullo, 1980)
-------
2-20
Arvada plans on putting most of its Clear Creek water into Blunn
Reservoir, which is presently being constructed on Ralston Creek. They
plan to accomplish this by discharging their pro rata shares of Church
Ditch and Farmers Highline Canal water into Ralston Creek and re-
diverting it at a pump station located near where the Croke Canal crosses
Ralston Creek. Arvada1s Reno and Juchem and Slough Association water
will be diverted in the Croke Canal on an exchange basis and delivered to
the pumping station. During the times the Croke Canal is diverting,
additional water from Arvada1s Reno and Juchem and Slough Association
rights will be taken, up to the total of those rights or the remaining
flow in the Creek, whichever is less. Arvada will be making up, in the
plan of augmentation, any return flow water that would have historically
accrued to the stream by the former use of Arvada shares. The plan has
the effect of reducing the water flow between the Croke Canal and Slough
Association Ditch during those times when water may be exchanged between
those two facilities (Sullivan, 1980; Case No. 8083-75, 1975; Case No.
W-8762-77, 1977).
Westminster's decreed plan of augmentation and Northglenn's proposed
plan of augmentation should affect Clear Creek in about the same manner.
Both cities plan on diverting their shares of Church Ditch and Farmers
Highline Canal water for delivery to Standley Reservoir. Both cities
will be required to return augmentation water to the stream at the
headgate to make up for any return flows that would have historically
accrued to the river but will no longer be present because of the change
in point of use. Clear Creek flows will be slightly Increased at the
headgates due to the fact that the make up water for these return flows
is placed in the creek at one specific point rather than being distribut-
ed throughout the reach of the stream as historical return flows would
have returned. This statement is not entirely true in Westminster's case
in that Westminster is claiming some return flow from lawn irrigation
that reaches Clear Creek by way of Little Dry Creek about one-third mile
west of Pecos (Case No. W-8743-77, 1980).
Northglenn also plans on implementing an exchange with Farmers
Reservoir and Irrigation Company (FRICO). In this exchange Northglenn
-------
2-21
will use FRICO water stored in Standley Reservoir and replace this water
with treated sewage effluent for the benefit of the FRICO shareholders.
This exchange will not affect Clear Creek flows or return flows (Case No.
79-CW235, 1979; Case No. 79-CW236, 1979).
Thornton has a proposed plan of augmentation which involves using
their rights to Clear Creek and Platte River Ditch water to augment flows
in the South Platte River caused by pumping Thornton's South Platte
alluvium wells out of priority. This would have the effect of augmenting
flow in Clear Creek near the mouth, although no point of return has been
established (Case No. W-7851-74, 1974). Thornton also has plans to
utilize Standley Reservoir in roughly the same manner as Northglenn and
Westminster, although no plan of augmentation has been filed to date.
Coors will be diverting water from their wells for the purpose
of using it in their brewing process. The general location of the
wellfield is shown in Figure 2-2. Water from the wells leaves the
brewery as product. Water from the Jefferson Storage System will be
used for domestic use and process water. Coors has a third point of
diverson at Coors Industries Ditch. Most of the water diverted at this
point is used in the cooling process. All of these water rights are
fairly junior. In order to be able to divert water, Coors has developed
an augmentation plan which will utilize its ownership in the various
ditches on Clear Creek. According to the plan, during times when Coors'
water rights are out of priority, Coors will add up all of its diversions
associated with the wells, Coors Industries Ditch and the Jefferson
Storage System and subtract from this the amount of discharge to Clear
Creek from its various cooling water and wastewater return points. The
difference will be the amount of water that needs to be replaced by
Coors. They will do this by returning to the stream their share of the
water diverted by the most senior ditches in which they have ownership.
The plan has the effect of increasing flows slightly in Clear Creek in
the stretch between the Church Ditch headgate and the Coors Industries
Ditch. Between the Coors Industries Ditch and the Slough Association
Ditch, creek flows are reduced from historical flows due to increased
-------
2-22
upstream diversions. Below the Slough Association Ditch, no change is
noticeable in the creek (Consolidated Case Nos. W-8036(75) and
r-J-8256(76), 1977).
There are several matters concerning Clear Creek that are presently
being litigated. Some of these, such as the Arvada, Northglenn and
Westminster plans of augmentation, have been discussed above. In addi-
tion, proposed revisions of in-stream water quality standards for Clear
Creek discussed in more detail elsewhere in this study, have been
reviewed in hearings before the Colorado Water Quality Control Commission
during Summer, 1980 (Colorado Department of Health, 1980). Numerous
ditch companies and industrial-municipal users are opposing this reclas-
sification for one reason or another. There are other minor disputes on
the stream such as the one between Arvada and the Consolidated Reno and
Juchem Ditch concerning the structure of the ditch company and one
potentially between the City of Golden, Northglenn, Coors and FRICO
concerning the ownership of the Berthoud Pass Ditch which diverts western
slope Fraser River water to the Clear Creek Basin.
2.3 STREAMFLOWS
The USGS maintains two gaging stations on Clear Creek that relate to
this study. The upper station is Clear Creek near Golden and the lower
is Clear Creek at mouth near Derby. The locations are presented on
Figure 2-2. For the period 1928-1976, the average annual flow at the
Golden gage was about 157,000 acre-feet (A-F). The lowest flow of record
was 68,200 A-F in 1954; the highest flow was 283,000 A-F in 1957. For
the same period of record, the average annual flow at the Derby gage was
about 67,000 A-F. The lowest annual flow at Derby was 10,900 A-F in
1954 and the highest was 187,000 A-F in 1965.
The flow in Clear Creek changes considerably in the 17-nile stretch
between the gages. Most of the flow reductions that occur are due to the
numerous diversion ditches that take water from Clear Creek. Except
during periods of high runoff, it is very common for one or more of the
various ditches to divert all of the flow in the creek. Due to these
-------
2-23
diversions, the flow in Clear Creek is an artificial regime; it bears
little or no resemblance to natural free-flowing stream conditions.
The operation of wastewater treatment plants (WWTP's) also affects
the flows in Clear Creek. Currently, four WWTP's discharge treated
effluent into Clear Creek: Coors' process wastewater, Wheat Ridge,
Arvada and Clear Creek Valley. Other plants have historically discharged
to Clear Creek but now discharge into the existing MDSDD interceptor. It
should be noted here that a fifth WWTP, Crestview, discharged treated
effluent to Clear Creek through April of 1977, at which time the plant
was closed.
To define existing conditions, a monthly water balance was attempted
for Clear Creek for the years 1975 and 1977. In 1975, the annual flow
past the Golden gage was 153,000 A-F and, therefore, it was considered an
average year. In 1977, the annual flow was only 75,500 A-F, the second
lowest flow of record. Thus, 1977 was taken as a dry year. The flows
passing the Derby gage for 1975 and 1977 were 62,800 A-F and 15,600 A-F,
respectively.
The flow information gathered was of three types: diversion
records, wastewater flows and Coors flows. Diversion records were
obtained from the State Engineer's office. The records were judged to be
accurate except as they applied to Coors. Wastewater records were
obtained through personal communications and NPDES records. Generally,
the wastewater flow records were unavailable on a monthly basis.
Incomplete records were estimated by average daily flows as determined by
the annual flows.
Flow data for Coors1 operations was somewhat difficult to obtain.
Prior to aiid-1977, flow data for the Coors Industries Ditch (Golden
Milling Co. Ditch) was not included In the State Engineer's records.
However, under Coors1 Plan of Augmentation, Coors provides daily records
of all Coors flows to the District No. 7 Water Commissioner. The water
rights aspect of Coors' Plan of Augmentation were provided in Section
2.2.
-------
2-24
Make-up water that Coors supplies from its water rights in other
diversion ditches to offset depletions is handled by an accounting system
whereby water that Coors is entitled to at that ditch headgate is
effectively left in the stream by diverting it, measuring Coors' portion,
and then returning that portion to the stream. This fact complicates the
water balance analysis since most of the diversion records available
from the State Engineer's office only show total diversions and do not
show this return flow.
We have attempted tc reduce the complex Coors' data to a form usable
in monthly water balances. However, no records are available prior to
late 1975 and, therefore, monthly water balances cannot be performed
prior to that time. Prior to May of 1977, the Coors1 diversions and
replacements of cooling waters were not recorded by the Water
Commissioner. We have, therefore, had to make estimates for the cooling
water diversions based on the available records and from assumed
conditions on the stream.
Tables 2-4 and 2-5 show the calculations and flows determined for
Clear Creek for the months of January and September of 1977. These
months were determined to be the lowest flow conditions of the stream and
represent wintertime and late summer/fall irrigation season conditions.
Figures 2-3 and 2-4 are a graphical representation of the flow determin-
ation for the above two months. The months of August and May represent
stream conditions when flow in the stream is higher and are presented in
Figures 2-5 and 2-6. Table 2-7 summarizes the flow data used for stream
diversions. Table 2-6 summarizes stream return flows, and Table 2-8
shows the recorded monthly stream flows for the year 1977 at the above-
mentioned stream gages.
A critical low flow of 180 acre-feet or 3 cfs is shown on the
flow graphs, Figures 2-3 through 2-6. This figure (3cfs) is shown on the
basis that there is a minimum streamflow below which significant impacts
-on—aqua Lic~ habitat will occur due to the combined effects of water
quality degradation and habitat loss; this minimum flow would have to be
-------
STREAM
NILE POIN1 ON CIEAR CRKKK
(I) (2)
DISTANCE
BETWEEN
POINTS
(3)
18.30 Wt-lLtl DIlLh
18.00 Cliuri.li Ulli.li
18.00 Cliy of Co [Jo,,
I/. 34 USCS btre.lniC.lge
16.42 AgilcuUur.il Ullcli
16. 18 Cuoru liiduutriul Ditch
16. J3 r..,iiB Cu.illug Helu
16.3) furmura lllglilliie Caii.il
16.15 a HI i a Cooling Retiirn(OOB)
16.12 Coura Cuulliig lli:Ciirii Eafclus
14 IM C..oru MM IP H«l""« 0*>
_
.
-
-
-
-
950.4
-
-
-
-
-
-
-
370.1
-
.
2537.0
2543.5
23J8.7
2340.0
2355. 8
1061.6
„ 2012.9
2012.9
2016.0
20 16 . 5
2016.8
2019.5
1859.0
106 1.7
„ 2243.3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
WITHOUT , ,
UASTEHATER
1OTAL IMrORII
FLOW FLOW
(13) (14)
2537.0
2543.5
2328.7
2340.0
2355.8
1061.6
2012.9
2012.9
2016.0
2016.5
2016.8
2019.5
1859.0
1861.7
2243.3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
rO
hJ
01
-------
TABLE NO. 2-4 (con11.)
CLEAR. CHEEK FLOWS
JANUARY . 1977
(All Valued In Acre Feel:)
FLOW IN LRKtK BEFORE
REMAINING FLOW IN CREEK
SIREAH
MILE
(1)
13 42
IJ.42
12 96
12.22
11. J5
11.25
10 J8
10.25
9.61
8.20
7 50
6 70
6.31
6.1J
6.23
6.18
DIVEKSIOMS OR
DISTANCE WASTEUATER FblURN
BETWEEN TOTAL IMPORTED
POINT ON CLEAR CKEEK
(2)
HI lua & Euklna
{ 1102ft
Couia WWIP Return* '
Runt* & luLlltioi
Slough Attune lotion
South Side
Oulelte
N.U. L.ikcuooJ UUn*
trulLJale UUCP
Lund Culi.li
Cult, (•laved & Hughes
Ulitjt Ridge WWIP
CKiir Cicuk Val. WWII'
Arv.nl.i UWIP
Kulaluii Cii.uk
buy 1 uu
Kuruliiiu Dlicli
POIK1S
(3)
0
.46
.74
.87
.10
.87
. 13
.64
1.41
.70
.80
.J7
0
. 10
.05
.90
FLOU
(4)
4 81
0
16.0
41. B
72.1
14.2
44.5
4V. 0
71.3
143.2
156.0
421.8
580.6
657.5
1010.6
1012.2
FI.OU
(5)
0
0
0
0
0
0
0
0
0
0
0
251.1
40 J.I
480.0
480.0
480.0
CAIN IN
CREEK FLOW
BETWEEN
PO1I11S
<6)
0
16.0
2S.8
30.3
3.5
30.3
4.5
22.3
46.0
25.9
12.8
14.7
6.8
0
350.0
3 1
1.6
28.0
DIVERSION (LOW
BY DI1CIIES
TOTAL IMPORTED
DIVERSION
(7)
48.1
-
0
0
61.4
0
-
_
-
0
-
-
-
_
0
0
DIVERSION
(8)
0
-
0
0
0
0
_
_
-
0
-
_
-
-
0
0
RETURN INCLUDING
FLOWS UASTEWA1EB(C>
TOTAL IMPORTED TOTAL 1HPOH1EU
WATER WATER FLOW
(9) (10) (11)
0
0 00
16.0
41.8
10.7
14.2
44.5
49.0
117.3
143.2
251.1 251.1 «07.l
152.0 152.0 573. B
76.9 76.9 657.5
1007.5
1010.6
1012.2
FIOW
(12)
0
0
0
0
0
0
0
0
0
0
251.1
403.1
480.0
480. 0
480.0
480.0
WITHOUT
WASIEWATEB (c)
1UTAI. IllTOaiED
FLOW
(13)
0
0
16 0
41.8
10.7
14.2
44.5
49.0
117.3
143.2
407.1
573. a
657.5
1007.5
1010.6
1012.2
FLOW
(U)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
to
ro
eft
-------
TABLE MO. 2-4 (concluded)
CLEAR CHEEK FLOWS
JANUARY . 1977
(All Vdluee In Acre Feet)
FLOW IN CREEK BEFOME
REMAINING FLOW IN CHEEK
STREAM
HUE
(1)
5.28
3 69
3 69
3.25
J.24
3.03
3 03
.52
0
POINT ON CLEAR CHEEK
(2)
tinder Ditch
UeatuliiBler UUfP
1 Illlu Uiy Creek
Uisteri! r.ivlng
Cieatvluw WUTP
Colorado Ag. Ditch
Clcjr 1,'iuek 6 Plutte R.
U.S.C.S. Stream Cage
Suulh Pintle River
DISTANCE
BETUF.tN
POINTS
(3)
1.S9
0
.44
.01
.21
0
Ditch
2.51
.52
DIVERSIONS OK
WASTEUATER RETURN
TOTAL IMPORTED
FLOW FLOU
(4) (5)
1040.2
690.6
690.6
774.3
776.5
841.8
847.8
926
942.2
480.0
480.0
480.0
480.0
480.0
480.0
480.0
480. 0
480.0
GAIN IN DIVERSION FLOU HETURN WASTEUATER
CREEK FIjOU BY OlldlRS FLOWS 1OTAI. IMPORTED
HETUKKN 10TAL IMPORTED TOTAL IMPORTED p.™. FLOU
POINTS DIVERSION DIVtRSIOH WATER WATER mt n,v
(6) (7) (B) (9) (10) * '
A&I.2 tsa.n
49
0
70
13
6
0
78
16
399.0
.4
.0
.7
.3
.5
0
0
.0
.2
0 -
690
760
1.9 0 "6
64.8 0 84i
o 841
0 . . «*'
926
942
.6
.5
•2
.3
.a
.8
.2
480.0
480.0
480.0
480.0
480.0
480.0
4BO.O
4BO.O
•*a\lll«'U*
WASTEWATEK
10TAL IHPOI
FLOU FLI
(13) (11
161.2 O
210.6
280. S
296.2
361.3
367.8
367.8
446.0
462.2
0
0
0
0
0
O
0
O
Totals 965.1
Apparent gain between atrodu gages - 931.3 AF
4427.3
1867.2
(a) I iid lea ecu wantouuter from Arvuda. Ulieat Ridge and Clear Creek Valley planLa
(b) IciJIcutca Nl'DKS permit discharge point
-------
TABLE HO. 2-5
CLEAR CREEK FLOWS
SEPTEMBER , 1977
(All Valuea In Acre Feet)
SIKtAH
MIIE
(I)
IB. JB
18.00
18 00
17.34
16.42
16.38
16.31
16.33
16 15
16.12
16.10
15.94
15.6.1
15.47
14. UD
14.110
14. BO
rOINI ON CIEAR CULEK
(2)
Welol. Dllch
Cliuii.li 1)1 tcli
Clly ot CulJun
USUS Slrc.im Cdge
AIJI Icullural UlLi.li
Coo i a lailuuLrlal DI Lull
(b)
Cuuru Cooling Helurn(006)
Fiiriiiura lll|;lilliie Ciiuul
Cum a Cool I iiB Ruluin(OOO)
Coucu Cooling Rclurn(OIO)
Coma Cooling Return (005)
Cuura Cooling Kelurn(007)
U.iiiiuinuklL III ti-h
leu, Slcwurt & Eaklim
FLOW IN CREEK BkPORB
REMAINING FLOW IN CHEEK
Ciokt. L.HIM!
Hot ky Mountain Dllcli
DIVERSIONS OR
SI'ANCb WASTtWATEH RETURN
TUEEN rilfAL IMPORTED
OINIS FLOW
(3)
.30
0
.66
.92
.04
.05
0
. IB
.03
.02
.16
.Jl
.16
.67
0
0
. J8
(4)
4975
4986
4986
4690
4716
J647
1278
3837
1478
1478
1479
14A4
1492
1101
94 J
943
943
.3
.1
.1
. I
.9
.0
.5
.0
.9
.5
.O
.8
.1
.5
.5
.5
FLOW
(5)
712.8
712.8
712.8
712.8
712.8
0
0
0
0
0
0
0
0
0
0
0
0
RAIN IN DIVERSION Fl OU
CREEK FLOW BY DITCHES
BETWEEN TOTAL IMPORTED
POINTS DIVERSION
(6)
10.
0
IB.
26.
1.
1.
0
5.
.
_
4.
B.
4.
19.
0
0
74.
(7)
0
8
0
314.8
7
_
1
1118.7
1
2371.3
4
_
2393.8
|
9
_
6
_
5
_
8
556. B
5
176.6
O
-
0
558.6
2
DIVERSION
(8)
0
0
0
_
712.8
0
_
0
_
.
_
_
0
0
_
0
0
KETURN INCLUDING
FLOWS WASTEWATEH
TOTAL IMPORTED TOTAL IMPORTED
WATER WATER FLOW
(9) (10) (ID
4975.
4986.
4671.
4690.
49.4 - M«-
1276.
2559.5 0 W31.
29.2 - ""•
0 "'<*•
0 1478.
0 1479.
0 >*84-
160.6 - >°96-
924.
0 0 943.
943.
384 .
3
1
3
0
8
6
5
9
0
9
5
0
6
5
5
5
9
FLOW
(12)
712. B
712.8
712. B
712.8
0
0
0
0
0
0
0
0
0
0
0
0
0
UUIIUUT
WAS'lEWATER
TOTAL IMPORTED
FLOW
(13)
4975.3
4986.1
4671.3
4690.0
3646. B
1276.6
3837.5
1472.9
1478.0
1478.0
1479.5
1484.0
1096.6
924.5
943.5
943.5
384.9
FLOW
(14)
712.8
712.8
712.8
712.8
0
0
0
hJ
0 1
ho
0 °°
O
0
0
0
0
0
0
0
-------
TADI.B NO. 2-5 (ron't.)
CLEAR CREEK FLOWS
SEPrKMIIER , 1977
(All Valued In Acre Feel)
FLOW IN CREEK BEFORE
REMAINING Fl OU IN CHiEK
DIVERSIONS OR
SIKfcAM
MILE
(0
13.42
13.42
12.96
12.22
II. 15
11.25
10. 18
10 25
9.61
8.20
7.50
6. 70
6. JJ
6.1)
6 2)
6. IB
rOIHI ON CIEAR CHEEK
(2)
Ml lea & Eaklna
COUTH VWI'P Return......
(002)
Runti & Jin:hi±u
Slough AaauLlutlon
South Side
OulcLlu
N.W. Lnkcuuod WHIP
Frill J.I l« WWTP
Luna Culcli
Coil, Graved & MngllCd
When 1 Hldge WWII'
Clear Crk. Val. WUIP
Aivj.1,1 WUIP
ILilntuii Cicuk
Buy lt!ti
Kerahuw Dltcli
DISTANCE
BETWEEN
POINTS
(3)
0
.46
.74
.87
.10
.87
.13
.64
1.41
.70
.BO
.37
0
. 10
.05
.90
WASTEUATER RETURN
TOTAL
FLOW
(4)
459.1
240.8
564.2
604.0
116.2
121.6
49.6
56.6
91.0
195.5
97.0
325.3
483.6
558.0
1042.3
1045.1
IMPORTED
FLOW
(5)
0
0
0
0
0
tt~
0
0
0
0
0
204.0
351.1
425.5
425.5
425.5
UAIN IN
CREEK FLOW
BETWEEN
POINTS
(6)
0
24. 7
3). 8
46.8
5.4
46.8
7.0
34.4
61.7
42.8
21.3
24.3
11.2
0
4/R.8
S.I
2.8
49.3
DIVERSION FLOW RETURN INCLUDING
BY DITCHES FLOWS UASTEWATEH
TOTAL
DIVERSION
(7)
218.3
_
0
534.6
0
118.8
-
-
-
119.8
-
-
-
_
0
615. 8
IMPORTED TOTAL
DIVERSION WATER
(B> (9)
0
298.7
0
0
0
0
-
-
-
0
204.0
147.1
74.4
_ _
0
0
IMPORTED 101AI.
WAVER FLOW
(10) (11)
240.8
0 539.5
564.2
69.4
116.2
2.8
49.6
56.6
152.7
75.7
204.0 301.0
147.1 472.4
74.4 558.0
1036.8
1042.3
429.3
IMPORTED
FLOW
(12)
0
0
0
0
0
0
0
0
0
0
204.0
351.1
425.5
425.5
425.5
425.5
WITHOUT
UASlbWATER
TOTAL
FLOW
(13)
240.8
539.5
564.2
69.4
116.2
2.8
49.6
56.6
152.7
75.7
97
121.3
132.5
617.4
622.9
9.9
IMPORTED
FI.OW
(14)
0
0
0
0
O
O
0
fs>
0 1
\n
0
a
a
a
a
a
a
0
-------
1ABI.E HO. 2-5 (concliideil)
CLEAR CHEEK FLOWS
SEPTKHUKR . 1917
(All Values In Acre Feet)
FIOU IN CKEKK BEFORE
REMAINING FLOW IN CHEUK
SI REAM
MILE
(1)
5.28
J 69
3.69
3.^5
3.24
3.03
J.03
.52
O
I'UINT ON CI.EAK UREEK
(2)
Mdlier Ditch
UeuLiiiliitiler UUTP
1.1 L lie Dry deck
Ufeutcm I'uvliig
Cicstvluu UWIP
Colurailo Ag. Illlcli
Cluui Clunk & Plntte R.
USLb Stream Uafjc
boiuli I'luttu River
DISTANCE
BETWEEN
I'OINIS
(3)
I.S9
0
. 44
.01
.21
U
U.
J.51
.52
DIVERSIONS OR CAIS IN DIVERSION FLOW
WASTEWATER RETURN CREEK FLOW BY DITCHES
TOTAL IMPORTED BETWEEN TOIAL IMPORTED
>LOU
(4)
478.8
249.5
249.5
366.3
366.9
378.5
37H.5
138
166.6
FLOW POINTS DIVERSION DIVERSION
(5) (6)
87.
^j
92.
24.
m
II.
J
133.
23.
(7) (8)
316.8 0
5
_
6 -
2
-
6
_
6
0 0
378.2 0
0
_ _
6
— —
RETURN
TOTAL IHTORTLI) T*
INCLUDING
WASTEWATER
L IIIPOKTEU
UATER WATER FLOH
(9) (10) <">
162.
249.
342.
0 0 366.
366.
378.
_
138.
166.
0
5
1
3
9
5
3
0
6
FLOW
(12)
162.0
162.0
162.0
162.0
162.0
162.0
.3
.3
.3
U11IIUUT
WAS1EWATER
101AL IMPORTED
FLOW
(13)
-2!>7.4 0
87.5
180.1
204.3
204.9
216.5
-161.7 0
138. 0
166.6
KLOU
(14)
0
0
0
O
O
O
0
0
O
to
|
LO
Totula 1600.1 9792.9 712.8
Apparent Cain lletwuun Si ream Cagea - 1403
3S22.9
(a) Waatcwoicr re (ere tu existing Arvaila, Uliaut Rlilgc. and Cleat Creek Valley plants.
(It) IndlralCB MPOES permit discharge point.
-------
PAGE NOT
AVAILABLE
DIGITALLY
-------
TABLE NO 2-6
CLEAR CREEK
KliTURN FLOW
IRRIGATION YEAR 1977
FACILITY
Coora Cooling Water
Coors Aiigmuntatlnn Muter
NOV
1700
DEC
1600
JAN
950
0
'FEU MAR
1440 1772
128.7
'APR
2200
'MAY
2803
34.9
JUNE
3187
JULY
3960
AUC
3601
7.2
SEPT
2560
239.2
OCT SUM
2078 27,851
106.2
Coora/Coldcn W.W.T.P.
Wheatrldge W.W.T.P.
287.0 324.0 370.1 323.1 331.2 323.2 422.0 375.7 325.4 351.0 298.7 297.3 4028.6
207.0 145.7 251.1 212.8 244.9 228.0 238.7 237.0 213.9 173.6 204.0 232.5 2589.2
Clear Creek Val. W.W.T.P.
Arvada W.W.T.P.
Western Paving
Crcstvlew W.W.T.P.
Totals
147.1
76.9
.9
45.0
152.0
74.4
1.9
47.0
152.0
76.9
1.9
64.8
1866.8
137.3
69.5
1.7
47.5
152.0
76.9
1.9
45.2
2752.8
147.1
74.4
1.8
42.3
152
76.9
1.9
3729.4
147.1 152
74.4 176
1.8 0
PLANT
152
.9 76.9
0
CLOSED
4 36 1 . 7
147.1
74.4
0
3523.4
152
76.9
0
2942.9
1789.7
905.4
13.8
f
ui
Notes:
1. No data avaJlable for Coors Cooling Water returns for the months of November 1976
through April 1977. Values shown for these months are estimates
2. Coors Augmentation Water shown only Includes waters that were actually diverted through
ditch headgaies and then returned to the stream
3. The return flows for the Coors/Goldcn WWTP was assumed to be transferred directly
to the Croke canal from November 15 thru March 31; For the rest of the year the return
flow was assumed to return to Clear Creek near the Miles & Eskins lleadgate.
-------
Table No. 2-7
Clear Creek Diversions
Irrigation Year 1977
SirucLure
Nov
Dec
Jan
Feb
Mar
Apr
May
June
July
Aug Sept
Oct
Sum
Welch DUch
Cliurcli Ditch
City of Coldon
Agricultural IHtcli
Coors Industrial D.
Farmers UJghllne
Uannaniiiker
I.ec, Stewart & Esklns
Croke Canal
Rocky Mountain I).
MI leu & l-sklns
Keiio tn .lucliem 1).
SLougli AasocfatJon
Soutli Side
Court, Craves & Hughes
lloyles
OlLcli
0
0
207.9
0
1709.7
2544.3
224
99
1294.9
0
0
0
0
59.4
0
0
0
0
0 83.2
(194)
0 2467.1
0000
0000
214.8 214.8 194.0 214.8 207.9 213.8
0000 242.2 839.5
1599.8 1294.9 1445.4 1993.9 2188.5 2651.6
0000 1893.9 4296.6
152.5 0 17.8 83.2 799.4 1014.4
0 0 30.7 92.1 122.8 352.4
2864.1 2243.3 1865.2 2183.9 824.7 0
(26.7)
000 519.4 1861.8
0
0
0
0
0
0
0
0
0
0
0
0
0
0 178.2
0 229.7
0 1314.7
61.4 61.4 55.4 61.4 59.4
24.8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 118.8
0 71.3
0 38.6
0 205.9
477.2
(27.7)
2991.8
2059.9
(136.6)
1496.9
3130.4
6737.0
823.7
532.6
0
2666.9
31.7
297.0
1431.5
4.0
219.8
169.3
96.0
485.1
257.4 154.4
0
0
586.1 0
(51.5) (16.4)
461.5 296.2 314.8
(1049.4)(993.9)(712.8)
1524.6 1342.4 1118.7
3779.8 3174.5 2371.3
3181.9 2746.3 2393.8
456.0 581.3 556.8
310.9 178.2 69.3
000
1075.9 431.8 305.3
0 .8 106.9
130.3 34.7 0
1142.5 637.6 534.6
000
174.2 137.6 118.8
181.2 160.4 119.8
25.7 0 0
538.6 465.1 615.8
0
0
211.5
435.6
2006.9
2648.9
486.3
120.8
0
314.4
48.1
0
508.9
0
87.1
114.8
0
295.0
972.2
(221.7)
6045.0
(67.9)
2957.9
(2892.7)
6999.9
26346.7
26478.7
5195.4
1908.8
11276.1
(26.7)
7175.5
365.7
691.7
5569.8
387.2
856.3
816.8
160.3
2605.7
-------
Table No. 2-7
(Continued)
Structure
Nov
Dec
Jan
Feb
Mar
Apr May
June
July Aug Sept
Oct
Sum
Fisher I)J toh 386.1 399.0 399.0 360. A 399.0 672.2 956.3 954.4 952.4 645.5 316.8 568.3
Colorado Ag. Ditch 000000 712.8 1989.9 427.7 000
Clear Creek & Platte R. 0 0 0 0 0 0 2063.2 2578.0 1366.2 881.1 378.2 778.0
To ta1 a
7009.4
3130.4
8044.7
(26.7)(194) (164.3)(1100.9)(1010.3)(712.8)
6525.3 5291.6 4213.4 3968.9 5028.3 7530.4 19694.7 27319.1 16572.911868.1 9320.9 8660.6
(3209.0)
125994.2
(a) Numbers in ( ) .indicate Imported water
Table No. 2-8
Clear Creek Cages
Irrigation Year 1977
Stream Gauge
Clear Creek
Col dun Cage
Clear Creek
lie r by Cage
Nov
3710
1300
Dec
3180
1270
Jan
2340
926
Feb
1890
1010
Mar
2330
1050
Apr
4690
1370
May
11870
1710
June
22710
5300
July
9900
2540
Aug
6150
434
Sept
4690
138
Oct
4360
155
Sum
77820
17203
10
u>
-------
2-38
maintained in the future to avoid adverse streamflow impacts on aquatic
habitat. However, 3 cfs has not been derived by any technical analyses,
but is only an assumed value for discussion purposes.
The Colorado Division of Wildlife has suggested a flow of 15 cfs
which will "preserve the natural environment to a reasonable degree."
However, Clear Creek has net been a "natural environment" for 120 years,
evidenced by the fact that 15 cfs is only exceeded throughout the reach
below Golden during the runoff period (Figure 2-6). The Colorado Water
Conservation Board has set minimum flow values for several small streams
in the Williams Fork River Drainage of from one to five cfs. These are
designed to protect trout fisheries from the dewatering effects of water
supply diversions and include higher flow values during late summer.
Setting of similar standards for a warm water fishery along Clear Creek
would provide a goal for continuing efforts in establishing a fishery and
preserving overall in-stream values.
The monthly water balances help to define the existing condition in
terms of monthly average diversions, return flows, and stream flows.
There are two seasons of water use: winter and summer. Most of the
diversion ditches take water from about April through October (the summer
season), and use it primarily for irrigation. From November through
March (the winter season), there are five ditches that divert significant
amounts of water for primarily municipal and industrial use: the
City of Golden, Coors, Wannamaker, Croke and Fisher.
The two largest winter diverters are Coors and the Croke Canal.
Essentially, all of Coors' diversions are returned to Clear Creek by
the time it reaches Croke Canal. The Croke Canal then takes effectively
all of the flow in Clear Creek, including the Coors process WWT?
effluent. Thus, during the winter season, Clear Creek is dry below
the Croke. Flows are critically low (less than 3 cfs) until the creek
reaches the vicinity of Ralston Creek. At this point, Clear Creek
undergoes substantial gains in flow from Ralston Creek and the Wheat
Ridge, Clear Creek Valley and Arvada WWTPs. Downstream of this point,
-------
2-39
the flow remains above the critical level. A portion of the avail-
able water is diverted by the Fisher Ditch, but the flow remains above
the assumed critical flow.
Flows during the summer season are of two types: runoff months
(generally May, June and July) where flow is plentiful, and non-runoff
months where the amount of water available is limited. During May of
1977 there are no areas where monthly average flow becomes critically low
(less than 180 A-F/mo (3 cfs) ).
The situation is quite different in the non-runoff summer months.
September is a fairly typical base month for low flows. With reference
to Table 2-5 and Figure 2-4, there are three locations of critical flow.
The first reach with critical flows is below the Slough Association Ditch
headgate and extends to the Wheat Ridge WWTP. With the contributions of
the three WWTPs and Ralston Creek, the flow in Clear Creek rises well
above the critical low flow. However, the Kershaw Ditch (just downstream
of Ralston Creek) diverts over half of the Clear Creek flow. About 1
mile further downstream the Fisher Ditch diverts enough water to bring
the remaining flow in Clear Creek to a critical low flow (less than
180 A-F/mo). Natural gains increase the flow to above critical flow
until the Clear Creek and Platte River Ditch is reached. This ditch
diverts all flow in the stream leaving the flow below the headgate at
essentially zero. Although Clear Creek accrues some gains in the flow
below the Fisher Ditch, the flow remains at a critical level as it
continues downstream to the South Platte River.
The methodology used for the water balances is a summation of
inflows and outflows. The flow at the Derby gage plus the sum of the
diversions minus the WWTP inflows usually gives a value higher than the
flow at the Golden gage. Thus, the river experiences a net gain. The
gains have been apportioned to major side drainage inflow points and
to creek reaches on a per-mile basis, drawing on discussions with Dale
Anderson and Coors combined with the known diversions. The apportioning
-------
2-40
is only approximate; no data is available that accurately defines tribu-
tary and other miscellaneous Inflows to the river. This is true for the
flows contributed to Clear Creek from Lena Gulch, Ralston Creek and
Little Dry Creek which are important sources of water for the ditches or.
the lower portion of Clear Creek. For the low flow months, reasonable
estimates can be made for these flows based on diversions downstream of
these major drainage flows.
The same type of water balance analysis was not performed for 1975.
The lack of accurate data on Coors' flows would induce enough error in
the calculations to render them meaningless. However, the flow informa-
tion that is available provides a comparison between dry year and average
year diversions. Therefore, the data available for 1975 diversions and
gage flows is presented in Tables 2-9 and 2-10. For almost all ditches,
the 1975 diversion amounts were much higher than in 1977, indicating that
if more water is available, it would be used, and the stream conditions
probably would not differ substantially from what has been presented for
a dry year.
Due to an absence of accurate historical records, a similar analysis
for conditions that existed from 1960 to 1967 (pre-interceptor) isn't
possible. However, the MDSDD Predesign Report (1961) contained the same
type of analysis for 1954 and 1959. That analysis contained some signif-
icant differences from this one. The MDSDD report apportioned net gains
or losses per river mile with no consideration of major side drainage
inflow. Coors1 operations appear to have been neglected. In 1954, there
were eight WWTP's discharging into Clear Creek. Combined, they dis-
charged about 3,560 A-F of treated effluent into Clear Creek. In 1977,
the sum of the discharges of the Wheat Ridge, Clear Creek Valley and
Arvada WWTP's amounted to 5,285 A-F.
In general, with the above differences taken into account, the
Predesign Report showed very similar flow regimes. That is, critical
flows occurred at the Croke Canal during the winter season, and below the
-------
TABLE 2-9
CLEAR CREEK DIVERSIONS
IRRIGATION YEAR 1975
STRUCTURE
Welch Ditch
Church Ditch
City of Golden
AgrLcuitiirdI Ditch
Coors Industrial D.
Fanners IlighlLne
Wannaiiiciker D.
Lee, Stewart & Eskins
Croke Canal
Rocky Mountain D.
Miles b Eskins
Reno & Juchein D.
Slough Association
South Side
Oulctte
Court, Craves & Hughes
Boyles
Kersluw Ditcli
Kiblicr Ditch
Colorado Ag. Ditch
Clear Crk. 4. Platte R.
Totals
NOV
0
0
208
0
-
600
224
168
2980
95
214
0
0
137
0
0
0
0
297
0
0
4923
DEC
0
0
215
0
-
0
152
151
2973
0
198
0
0
196
0
0
0
0
584
0
0
4469
JAN
0
0
131
0
-
0
202
165
2809
0
194
0
0
192
0
0
0
0
497
0
0
4190
FliB
0
0
139
0
-
0
174
159
2686
0
166
0
0
119
0
0
0
0
471
0
0
3914
MAR
0
0
154
0
-
0
293
184
3222
0
198
0
0
95
0
0
0
0
244
0
0
4390
APR
0
1267
168
83
-
1275
493
52
933
143
255
0
0
129
0
0
0
0
881
0
51
5730
MAY
162
1857
184
1204
-
5625
853
386
341
568
220
275
986
152
73
137
59
251
1329
645
1447
16754
JUNE
622
4491
204
1374
-
8183
1251
1087
8255
946
214
255
1249
218
71
178
89
677
1576
1182
1420
33542
JULY
923
5001
216
2053
-
12676
738
1083
0
1766
222
311
1655
224
73
178
85
699
1600
1608
2180
33291
AUG
691
2447
216
1792
-
4948
618
612
0
1536
222
457
1725
224
73
154
61
699
1378
1139
1980
20970
SEPT
309
0
208
1725
-
2612
431
158
0
240
214
22
796
216
71
149
30
677
1622
539
1970
11989
OCT
63
0
216
869
-
2683
422
137
0
253
222
22
701
224
71
149
0
699
950
103
994
8779
SUMS
2,770
15,063
2,259
9,100
-
38,602
5,851
4,342
24,199
5,547
2,539
1,342
7,112
2,126
432
945
324
3,702
11,429
5,216
10,042
152.942
NOTE: No data available for Coors Industrial Ditch in 1975
TABLE 2-10
CLEAR CREEK GAGES
IRRIGATION YEAR 1975
STKIJAM CAGE
Clear Creek
Golden Gage
Clear Creek
Derby Gage
NOV
4040
1650
DEC
2910
1030
JAN
2800
1130
FED
2640
930
MAR APR
2990 2730
1150 1400
MAY
10750
2750
JUNE JULY
43460 44430
23090 25030
AUG
11960
2310
SEPT
7510
879
OCT
4860
685
SUMS
141,080
62,084
to
-------
2-42
Slough Association, Fisher and Che Clear Creek and Platte River ditches
during the summer season. The Predesign Report concluded that if all
WWTP's on Clear Creek entered MDSDD and used the proposed 1967 inter-
ceptor, then the water rights of the Fisher, Clear Creek and Platte River
and the Colorado Agricultural Ditch would be injured.
However, not all wastewater flows are being sent to the MDSDD
interceptor, and it appears that the above-mentioned ditches are not
being injured. Table 2-11 presents annual flow and diversion data for
the USGS gages and the three most downstream diversion ditches for three
average years and two dry years. Comparison of dry year 1977 versus dry
year 1954 shows that the annual amounts of water diverted in 1977 are
very similar to the 1954 amounts. The same situation holds true for a
comparison of 1958 and 1956 versus 1975 (all three are near average). It
appears that the 1967 interceptor has not decreased the flows available
to the lower Clear Creek ditches. The Leonard Rice report (1978)
presented a trend analysis of the lower Clear Creek ditches that indicat-
ed decreasing trends in flow. However, the trend analysis was followed
by a disclaimer that stated: "Changes in diversion rates are not an
accurate indicator of the water rights impacts of Metro facilities and no
definite conclusions can be drawn from their analysis."
2.4 WATER QUALITY
2.4.1 General Considerations
Water quality in Clear Creek from Golden to the South Platte River
is linked closely with several auxiliary issues such as WWTP discharges,
stream diversions, upstream pollutant discharges, and land use. The
existing water quality conditions are best described in relation to these
continually changing other factors.
In general, water quality in Clear Creek is or has been adversely
affected by abandoned mine drainage upstream of Golden, sewage treatment
plant discharges and urban runoff. Due to the periodic near-total
diversion of the stream flow, irrigation return flows, groundwater
-------
TABLE 2-11
Annual FJows, Pre-and Post 1967
All values in Acre-Feet
Year
Dry Years
L977 1
1954 2
Average Years
1975 i
1958 2
1956 2
USCS Cage
Golden
75,520
77,820
68 , 200
140,300
141,080
147,960
138,030
USCS Cage
Derby
15,550
17,203
10,934
61,960
62,084
88,580
56,347
Fisher
7009
7632
11,429
6632
7715
Colorado
Agricultural
3130
2400
5216
3428
6168
Clear Creek 4.
I'Jactc Valley
8044
7201
10,042
8700
9956
Irrigation Year
Calendar Year (from the MDSDD PredesJgn Report)
-------
2-44
seepage and point source discharges are significant contributors to total
flow in several stream segments. Thus the impact of the pollution
characteristics of these sources on in-stream water quality can be
critical.
2.4.2 Water Uses and Discharges
Wastewater Treatment Plants
Previous sections have discussed water diversions and discharges
from sewage treatment plants on Clear Creek. Of particular importance to
the water quality issue is the depletion of stream flow caused by diver-
sions and subsequently the increased impacts of the treatment plant
discharges. Specific impacts and water quality data are presented in
later sections.
Urban Runoff
Another discharge to Clear Creek consists of runoff from storm
events and snowmelt. As discussed in earlier reports, pollution loadings
from storm runoff can be quite high and is related strongly to land use.
Urban runoff loadings are usually applied the length of the stream,
however the presence of storm sewers or surface drainage systems converts
these non-point sources to point sources.
In the Clear Creek basin, a significant portion of the urban area is
served by storm sewers, and the remainder is served by ditch or gutter
systems. Figure 2-7 shows the approximate areas served by storm sewers
and approximate discharge points. Much of the urban runoff not dis-
charged directly to Clear Creek is collected in Ralston Creek, Little Dry
Creek and Lena Gulch. Thus a significant portion of the non-point
pollutant loading from urban runoff is concentrated in the reach between
Kipling and Sheridan Streets.
Irrigation Return Flow and Groundwater
Another issue is the effect of ground water and irrigation return
flow to Clear Creek. Irrigation return flow may enter the stream through
-------
PAGE NOT
AVAILABLE
DIGITALLY
-------
2-46
ground water discharge or direct return by ditches and feeder streams.
This flow contributes nitrogen, phosphorus, dissolved solids and chemical
pesticides and fertilizers. Ground water flow pollutants are contributed
via infiltration of runoff water and by leaching of pollutants from
subsurface sources, such as landfills.
It is expected that the majority of the irrigation return flow is
discharged to Clear Creek in the upper half of the segment studied or by
way of Ralston Creek, Little Dry Creek or other small tributaries.
Irrigation flow contributions to ground water will occur from leaky
ditches and at irrigated sites. The locations of irrigated fields and
irrigation ditches are discussed and shown in other sections.
Potential subsurface sources of pollution in the basin include
septic tanks, sewer lines and existing and abandoned landfills. Figure
2-7 shows the approximate locations of known abandoned and operating
landfills. Present regulations signficantly reduce the ground water
pollution hazards from the operating landfills, however the pollution
contribution from the numerous abandoned landfills is difficult to
evaluate. Municipal landfills can contribute a wide range of parameters
including iron, manganese, calcium, nitrogen and organics. Due to the
relatively slow processes involved, landfill generated pollutants are
released over periods of years and possibly decades, depending upon the
types of materials deposited, methods of placement, quantities involved,
depth and size of landfills and ground water conditions. The concen-
tration of landfills adjacent to Clear Creek between Sheridan and
Broadway Boulevards, presents a high pollution potential.
Mine Drainage
Obviously, the upstream water quality conditions provide a base to
which downstream contributions are added. Upstream of Golden the primary
impact on water quality is drainage from abandoned mines. Two particular
areas contribute the most significant loading of metals and reduced pH:
-------
2-47
the Argo Tunnel at Idaho Springs and the North Fork of Clear Creek
flowing from the mining district around Central City (Holm, 1980).
These and other mine drainage sources in the basin have deteriorated
the upper Clear Creek water quality to the point where fish and other
aquatic species cannot survive. However the effects of this drainage
are markedly reduced by the time Clear Creek enters the study area at
Golden. Flow diversions and dilution further reduce these values through
the study area.
2.4.3 Water Quality Data
Water quality in this segment of Clear Creek has been measured more
or less continuously since 1967 at the USGS stream gages above Golden and
near the mouth at Derby (York Street Bridge). Data has also been col-
lected at other stations shown in Figure 2-1. This data is available
from the STORET file, and has been presented in numerous previous
reports.
Generally, the data shows that significant parameters, in terms
of standards, and environmental and public health effects, are fecal
colifo/rm, various metals, ammonia, phosphorus and chlorine. Tables
2-12 through 2-18 present summaries of the STORET data for these
parameters for selected months since 1976.
The general trends evidenced by these data support earlier analyses.
Phosphorus increases downstream from Golden, probably due to sewage
treatment plant discharges and urban runoff. Ammonia follows the same
pattern, however a more marked increase is noted in the lower portion
than in the upper. Fecal coliforms increase downstream from Golden with
the largest increase in the segment above Kipling.
Figures 2-1 and 2-7 show the locations of sewage treatment plant
discharges and urban runoff returns via storm sewers or major drainage
-------
2-48
Date
Table 2-12
Water Duality Data
Selected Averages
Fecal Coliform
(per 100ml)
Above Golden Youngfield
Kipling St.
5/76 -
9/76 -
11/76 -
5/77 -
9/77 -
11/77 -
5/78 -
9/78 -
11/78 -
5/79 -
9/79 -
7/76
10/76
3/77
7/77
10/77
3/78
7/78
10/78
3/79
7/79
10/79
(13) 614
(23) 18
(56) 824
2440
45
838
93
410
4071
75
93
(77) 1617
(1500) 483
260 (288) 140
8980
320
4648
564
396
71
—
^^ —
York St.
(586) 583 (1180)
(2300) 430 (1082)
(787)9,007 (5153)
11,012 (2455)
973
4060
1648
270
1170
430
330
( ) Indicates special studies data
-------
2-49
Table 2-13
Water Quality Data
Selected Averages
Ammonia (Total)
(mg/1)
Date
5/76 -
9/76 -
11/76 -
5/77 -
9/77 -
11/77 -
5/78 -
9/78 -
11/78 -
5/79 -
9/79 -
7/76
10/76
3/77
7/77
10/77
3/78
7/78
10/78
3/79
7/79
10/79
Above Golden
(.13) .16
(.31) .03
(.00) .38
.19
.20
.42
.08
.15
.39
.15
.05
Youngfield Kipling St.
(.147) .163
(.32) .233
.00 (.473) .542
1.2
.45
.49
.27
.203
. 284
.23
.056
York St
(.44) 1.90
(.24) 1.03
(6.49) 4.81
.825
1.3
6.55
.505
.52
4.56
-
.06
•
(.67)
(1.20)
(6.24)
(3.83)
( ) Indicates special studies data
-------
2-50
Date
5/76 - 7/76
9/76 - 10/76
11/76 - 3/77
5/77 - 7/77
9/77 - 10/77
11/77 - 3/78
5/78 - 7/78
9/78 - 10/78
11/78 - 3/79
5/79 - 7/79
9/79 - 10/79
Above Golden
(.00) .03
(.00) .01
(.02) —
Table 2-14
Water Quality Data
Selected Averages
Phosphorus -(Total)
(mg/1)
Youngfield
.03
.02
.09
.13
.05
.13
Kipling St.
(.08) .193
(.12) .186
(.24) .226
York St.
(.32). .568.
(.22) .64
(1.41)1.79
103
558
507
145
.49
.26
.33
1.12
.43
.28
( ) Indicates special studies data
-------
2-51
Table 2-15
Water Quality Data
Selected Averages
Iron (Total)
(lig/1)
Date Above Golden Kipling St. York St.
5/76 -
9/76 -
11/76 -
5/77 -
9/77 -
11/77 -
5/78 -
9/78 -
11/78 -
5/79 -
9/79 -
7/76 (740)
10/76 (1297)
3/77 (2200)
7/77
10/77
3/78
7/78
10/78
3/79
7/79
10/79
1000
720
1290
780
340
1330
1100
575
585
1200
977
(875) 650
(887) 1100
(720) 823
650
0
375
1842
433
513
900
330
350
(460) 430
(41) 937
(1958) 725
570
1200
894
607
1147
1500
567
(1238)
(743)
(715)
( ) Indicates special studies data
-------
2-52
Table 2-16
Date
5/76 - 7/76
9/76 - 10/76
11/76 - 3/77
5/77 - 7/77
9/77 - 10/77
11/77 - 3/78
5/78 - 7/78
9/78 - 10/78
11/78 - 3/79
5/79 - 7/79
9/79 - 10/79
Water Quality Data
Selected Averages
Zinc (Total)
(ug/l)
Above Golden Kipling St. York
(220)
(333)
(775)
400
—
590
325
200
635
330
278
479
303
343
(185) 300
(117) 180
(155) 133
200
80
135
293
390
94
120
70
50
(99) 41
(64) 110
(138) 40
60
90
183
40
49
165
23
St.
(113)
(25)
(25)
( )Indicates special studies data
-------
2-53
Table 2-17
Water Quality Data
Selected Averages
Copper (Total)
(Wg/l)
Date
5/76 -
9/76 -
11/76 -
5/77 -
9/77 -
11/77 -
5/78 -
9/78 -
11/78 -
5/79 -
9/79 -
7/76
10/76
3/77
Till
10/77
3/78
7/78
10/78
3/79
7/79
10/79
Above Golden
(23) 0
(44) 42
(77) 38
16
0
45
37
29
45
50
46
Kipling St.
(26) 0
(21) 34
(7) 16
27
0
26
37
12
11
28
11
York St.
0
(25) 8
(36) 18
(58) 17
0
3
24
7
15
31
11
(17)
(16)
(15)
( ) Indicates special studies data
-------
2-54
Table 2-18
Date
5/76 - 7/76
9/76 - 10/76
11/76 - 3/77
5/77 - 7/77
9/77 - 10/77
11/77 - 3/78
5/78 - 7/78
9/78 - 10/78
11/78 - 3/79
5/79 - 7/79
9/79 - 10/79
Water Quality Data
Selected Averages
Manganese (ug/L)
Above Golden Kipling St.
(157)
( 60)
(1050)
690 (248)
- (227)
1037 (250)
320
470
720
—
- 510
650
563
763
250
310
243
60
0
85
530
168
246
235
90
York St.
350
(250) 170
497
(538) 185
2100
840
330
223
615
345
333
(273)
(263)
(400)
( ) Indicates special studies data
-------
2-55
channels. Urban runoff is concentrated in the reach of Clear Creek from
Kipling Street through Sheridan Boulevard, as are sewage treatment plant
discharges. This probably accounts for the significant phosphorus and
ammonia increases.
Critical low flow reaches of the stream have been identified in
Section 2.3. In these reaches, the influence of various discharge? on
in-stream water quality is increased. Increases in ammonia, fecal
coliform, and phosphous concentrations in Clear Creek from the wastewater
discharges will become more pronounced during low flow conditions.
Sewage was estimated to comprise 70 percent of the flow in Clear Creek
between Wadsworth Boulevard and Ralston Creek during low flow periods of
January and September, 1977.
The metals analysed show a general decrease downstream from Golden.
Copper and zinc decrease throughout the segments under study, but iron
and manganese increase in the lower segment of the stream. Iron and
manganese are associated with landfill leachate and the concentration of
abandoned landfills in this lower segment of the stream may account for
these increases.
2.4.4 Water Quality Standards
Current state classification of water quality in Clear Creek
is established to provide for secondary contact recreation, domestic
water supply and fisheries: cold-water above Golden and warm-water
below. Table 2-19 lists some of the parameters established by the
Colorado Department of Health to meet this classification.
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2-56
Parameter
Fecal Co11form
(30 day avg.)
Dissolved Oxygen
Temperature
pH.
Turbidity
TABLE 2-19
EXISTING WATER QUALITY STANDARDS
CLEAR CREEK
Bl
Above Golden
1000/I00ml
6mg/l
maximum 68°F
maximum change 2°F
6-9
no increase greater
than 10 JTU
B2
Below Golden
1000/lOOml
5mg/l
maximum 90°F
maximum change 5°F
6-9
no increase greater
than 10 JTU
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2r57
2.5 FISHERIES - AQUATIC HABITAT
2.5.1 Present Aquatic Inhabitants
Five post-1967 fish collections were conducted on Clear Creek
from Golden to the South Flatte River. All collections were obtained
during a four-year period (1976-1980). These recent investigations of
Clear Creek have been pursued in response to the potentially altered
utilization of the stream, while earlier investigations were focused
on reservoirs and gravel excavation pits adjacent to Clear Creek and
associated with the Wheat Ridge Greenbelt between Youngfield Street and
Wadsworth Boulevard. The dates of collection and personnel conducting
the post-1967 surveys on Clear Creek are as follows: 13 December 1976
(Woodling, Colorado Department of Health), 29 August 1979 (Whittaker,
Colorado Division of Wildlife), 18 April 1980 (Mars, Colorado Depart-
ment of Health), 8 May 1980 and 9 July 1980 (NUS for Adolph Coors
Company). Results of the collections are presented in Table 2-20 adapted
from NUS (1980). Based on the lack of systematic sampling and incon-
sistent levels of identification, this data should only be used for the
qualitative assessment of the fish inhabitants in Clear Creek between
Golden and the South Platte River.
Habitat preferences of the Inhabiting aquatic organisms generally
reflect the habitat characteristics of the stream. However, since
some individual fish and aquatic macroinvertebrates, in particular, were
identified only to genus, characterization of each collection site
based on the food or habitat preferences of the aquatic organism in-
habiting that particular section of stream is unjustified, because
within each genus different species will prefer different habitats.
Therefore, considering the preferred habitat of the aquatic organisms,
Clear Creek can only be generally characterized.
The White Sucker (Catostomus commersoni), specifically, is found
throughout Clear Creek from the Croke Canal diversion to York Street.
This Catostomid tends to avoid rapid currents and feeds on a variety of
animal food but predominately on insects. The stomach contents of an
individual are as much determined by the availability of a certain food
-------
TABLE NO. 2-2U
White
Sucker
Sucker
SiH.keru
DllCI!
Cicuk
Clml.
K.iLliund
Mtiinou
Siinil
Militur
Cui,.
MlnnouH
/.*>!> liiuiu
Hi own
Uiilllienil
Crucn
iillll flail
Suiit lull
1 III'KIMIIOIIL
A-Hjy U.
Croke
Canal
A
C.iliiHtoiiHia
f.oiniieiaopl
em-klevi.
Ctlaci!;i_ 96
..
KlilnlcliLliyii
CuLariictuii
bcinotl lilb
At rui'kiLiil/iLiiif ~
l'Jlllli|l|lillUH
Hoirii|ila (lellcliisiis
Illlflt,!.! lIl'llMl.l
Cvui'luua Cue 11 la
Amu j in IIH
ncbuluuua
1 ujfoiul a
J.L-L">l>llu HI'..
li Ml ci li-ma
I9UO (Coon.) 0=A|irll 18, I960
29, 197
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2-59
as by its food preference (Baxter and Simon, 1970). The Longnose Sucker
(Catostomus catostonus) was collected only at the Croke Canal diversion
and Youngfield Street. The Longnose Sucker feeds predominately on
insect larvae, plant material, and small molluscs, and prefers much the
same habitat as the White Sucker. The remaining Sucker collections are
comprised of unspecified Catostomids, possibly being a combination of
the two previously mentioned species.
Several species of the family Cyprinidae (minnows) were collected
throughout the lower segment of Clear Creek. These species include the
Longnose Dace (Rhinichthyes cataractae), the Creek Chub (Semotilus
atromaculatus), the Fathead Minnow (Pimephales promelas), the Sand
Shiner (Notropis deliciosus), and the Carp (Cyprinus carpio). The
Cyprinids consist of a group of fish whose individual species members
are adapted to various habitats and maintain certain feeding preferences.
The Longnose Dace can be found in riffles of both large and small streams
and are typically omnivorous, feeding on aquatic insects and algae. The
Creek Chub prefers fairly clear water with gravel bottoms for spawning
and is largely carnivorous preferring insects, crustaceans, and small
fish. The Fathead Minnow was generally found from Youngfield Street
to York Street. This minnow tolerates turbid water quite well and is
usually found in this type of habitat. The Fathead Minnow is mainly
herbivorous but may feed on small aquatic insect larvae and can be
very prolific given proper spawning habitat including submerged objects
which are suspended for the attachment of eggs on the underside. The
Sand Shiner is usually found in very shallow water in permanent sandy
streams. Little is known about its feeding habits, but it is generally
considered omnivorous. The Carp usually feed by "rooting" in the mud
for bottom dwelling aquatic insects. This Cyprinid occurs typically
in lakes, reservoirs, and large rivers but occasionally will be found
in small streams in pools and quiet waters.
The remaining groups of fish collected from Clear Creek include
the Brown Bullhead (Ameiurus nebulosus), the Green Sunfish (Lepomis
cyanellus), and the Largemouth Bass (Micropterus salmoides). The Brown
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2-60
Bullhead is usually found in rivers and streams having muddy bottoms
which is adequate for nest buiding. The Brown Bullhead feeds primarily
on insect larvae, crustaceans, and molluscs. The Green Sunfish prefers
the pools in small- to medium-sized streams and feeds on insects and
small fish. The Largemouth Bass is generally found in the backwaters
of slow streams whose summer water temperatures exceed 75°P. The
Largemouth Bass is carnivorous, feeding predominately on smaller forage
fish.
Fishing pressure on Clear Creek between Golden and the South
Platte River is virtually nonexistent (Woodling, 1980). A majority of
the angling effort is directed toward the more productive inundated
gravel pits adjacent to Clear Creek.
Because benthic macroinvertebrate collections were initially
recorded as relative abundance for some samplings, tabulations for
the purposes of this report are not quantified. The qualitative results
of the benthic macroinvertebrate samplings conducted by Woodling (in
preparation) on 13 September 1976 and by NUS (1980) on 8 May 1980
and 9 July 1980 are presented in Table 2-21. The relative abundance of
each taxon is represented as follows: P = present (1-5 individuals),
C = common (6-50 individuals), A = abundant (over 50 individuals).
Table 2-21 was adapted from NUS (1980).
2.5.2 Potential Aquatic Inhabitants
A literature review has revealed little information concerning
fish collections on Clear Creek near Denver and prior to 1967. The
only documented collection found was that of a Silvery Minnow
(Hybognathus nuchalis) collected by W.C. Ferril on 7 August 1900 in
Clear Creek near Denver. The Silvery Minnow is usually found in the
plains streams of eastern Colorado (Ellis, 1914).
In the early 1900s, several fishery surveys were conducted on
streams to the north and south of Clear Creek. Table 2-22 presents the
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2-61
TABLE SO. 2-21
Selaeive Abundance of Xacro-Lnverteoracas
Collected from Clear Creek Below Golden
Trlcaopeara (Caddiaflies)
ithyacophlli dae
Biyaeeanila
iydropaychidae
gydropaycha
Srachyceneridae
Braehyeentrua aaerleanua
aydropciUdae
Placopcera (Sconefliea)
Pseronarcidae
Pteronarcella
Chloroperlldae
Parlldae
Heaoeroperla aaeifiea
Spaemaropcara (Mayfllea)
Baecidae
Baecis
Ephemarella
Trteorythodas
Odonaca (Dragonflias)
Goophidae
Ophiegonnhua
Coenagrloaidae
Olpcera (True files)
Chironooddae
CeracoGogonldaa
Xhagionidaa
Athartx pachypua
Crake Mclncyre Toungfield Kinling Wadsworth ?ecoa tort
Canal Screac Sereec Screec Boulevard Screec Screec
3A 3 A A A A 3
(5-8-30) (9-13-80) (7-9-30) (9-13-76) (9-13-78) (9-13-76) (9-13-76) (7-9-30)
SiBuliidae
Orthocladinae
Physa (Snails)
Hlrudiaao (Leeches)
Nenacoda (iouodvoras)
Amhipoda (Crustaceans )
?
.
C P P A
P C
? - ? -
. - - ? C
-
?
-
-
-
-
A - Joooliag (Colorado Oeparccene of 3ealca,
3 - HUS (1980)
? - present (1-5)
C - common (6-50)
A - aounoanc (acre chan 30)
sreoaracion)
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2-62
TABU SO. 2-22
Tish Species Collected "raa
Screams Hear
Clear Creek in che Early
1900s - from tills (1914)
Coaiaon
:'anan.s)
Suckley's Sudcar
Gray Sucker
?lacce River Suucer
"ine-scaled Sucker
Goldfish
Scone- roller
Greased Chuo
Western Red-
Sallied Dace
31ack-headed Minnow
rat-nead
Silvery Kinnov
Sucker-aouched
Minnow
Cayuga Shiner
Platte River Shiner
"escern Shiner
Comon Shiner
•ledfin
Creek Chuo
Horned Dace
Mountain Dace
So ray-head
Indian Chuo
Jerker
Dulcls Mionow
'Jestera Long-nosed Dace
leora ;lsh
Zaera Top-oinnou
Uccle Red Fin
Little Green rap-minnow
Green Suniish
31ue-Soocced Sunfiao
Iowa Darter
Jonimv Darrer
Scienciric 3oulaer Creeic
lame lear 3oulder
(i)
Catostorais co™wrsoni
aueklii I
Cacoscomus 3r4seus X
Carasalus auracus
CamDostoma
anomalun X
Chrosonus ervthroMscer
dakoeensia X
Pimeohales srooelaa
Hybognathua nuchalis X
Phenaeobius alraoills
SotTopls eayuija X
locropis jtacoleals X
Mo crop Is sevlla X
Soerools eornacus X
Nocrools lutransis
Semotilua acronaculatua X
Couesius d'ssl=ll
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2-63
findings of four surveys directed by C. Juday and J. Henderson in 1903
on Boulder Creek near Boulder, by M.M. Ellis in 1912 on Boulder Creek
six miles east of Boulder, by A.G. Vestal and M.M. Ellis in 1912 on
West Plum Creek near Castle Rock, and by C. Juday and C.W. Spangler
in 1903 on St. Vrain Creek near Longmont. Because of their proximity
to Clear Creek, these particular surveys were selected to determine those
fish species which possibly inhabited Clear Creek at the turn of the
century and do not inhabit it now. This is not to be interpreted
as being definite proof that these particular species also inhabited
Clear Creek in the early 1900s. However, based on the lack of data on
the subject stream, one can only extrapolate the probability of these
particular fish species occurring in Clear Creek. A brief comparison of
Tables 2-20 and 2-22 indicates a higher species diversity occurred around
1900 than does now. It should be noted that 15 of the 22 species in
Table 2-22 (Goldfish to Longnose Dace) are Cyprinids (minnows) and
species of this group have been generalized in Table 2-20. The only
species which occurred in any of the four early 1900 surveys and not in
the present surveys of Clear Creek include the Zebra Topminnow (Fundulus
zebrinus), the Little Green Topminnow (Fundulus floripinnis), the Iowa
Darter (Etheostoma iowae), and the Johnny Darter (Boleosoma nigrum
mesaeum). The Zebra Topminnow is a species of the shallow streams of the
plains, coming up to but not entering the true foothill streams (Ellis,
1914). The Little Green Topminnow, as described by Ellis (1914), is
found in the western portion of the South Platte drainage. The Iowa
Darter prefers cold rapid streams and is found throughout the northwest
portion of the Mississippi River drainage. The preferred habitat of the
Johnny Darter includes small spring-fed streams of steep gradient with
rock or gravel substrate (Cross, 1967). Based on the above findings,
there exists the possibility that the darters did inhabit Clear Creek
during a time when stream flows were more favorable. However, consider-
ing present stream flow variations and restrictions, prime habitat for
the Iowa and Johnny Darter is wanting in Clear Creek between Golden and
the South Platte River.
An additional ongoing study has been recently implemented by the
Colorado Division of Wildlife. This involves the initial planting of
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2-64
1,300 six-inch Channel Catfish (Ictalurus punctatus) on 1 August 1980 in
Clear Creek from Youngfield Street downstream through Wheat Ridge
(Woodling, 1980). The Colorado Division of Wildlife will be monitoring
this plant in the future to determine the extent of adaptability of the
Channel Catfish to this segment of Clear Creek.
2.5.3 Physical Stream Characteristics
For the purpose of aquatic habitat assessment, Clear Creek from
Golden downstream to the South Platte River will be divided into three
segments each of which has its own general characteristics. This will
include the following segments: (1) Golden to Youngfield Street, (2)
Youngfield Street to the Wheat Ridge Wastewater Treatment Plant (WWTP),
and (3) Wheat Ridge WWTP to the confluence of the South Platte River. In
most sections, the existing quality of stream habitat has been limited
due to an excess or a lack of various habitat-related parameters charac-
teristic to each segment.
Late summer stream flows, August through October, represented
in Table 2-5 (September, 1977) were chosen for assessing the present
adequacy of the stream for supporting a fishery. These flows are most
critical due to the subsidence of spring runoff and increased agricul-
tural utilization of the water remaining in the stream. The lack of
substantial instream flow can result in the stagnation of pools, should
they be present, causing severe oxygen depletions through lack of oxygen
transfer, organic decay and eutrophication (algal activity), and the
raising of water temperatures beyond the tolerance of most fish species.
Between Golden and Youngfield Street, stream flows fluctuate
frequently in response to water demands from agriculture and surrounding
municipalities. Table 2-5 indicates flows are generally adequate during
September to support a fishery from Golden to the Slough Association
ditch or Youngfield Street (4.2 miles). However, during January (Table
2-4) because of the rerouting of Coors WWTP effluent to the Croke Canal,
flows become critically low from the Croke Canal diversion to Youngfield
Street. Excessive channelization of this section of stream appears to be
limiting the perpetuation of a fishery. There is limited submerged
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2-65
aquatic vegetation and, due to fluctuating flow, most riparian vegetation
is located far from the stream's edge (Plate 1). The water quality in
this section is generally acceptable except for high concentrations of
residual chlorine which have been detected by Woodling (in preparation)
below the Coors process WWTP. For nine samples taken from Coors1
effluent on 13 December 1976, total residual chlorine averaged 0.7 mg/1
including three determinations of 0.0 mg/1. These high concentrations of
residual chlorine were, according to Wood ling, attributable to two
separate causes. Coors1 analytical methods were drastically underesti-
mating the residual chlorine concentrations. Since that time, Coors'
laboratory has acquired an amperometric tttration device which has
allowed the readjustment of the chlorine feed. The second cause lies in
the properties of the wastewater being treated. At the time the water
samples were obtained, Coors was treating both domestic and process
water. Some of the process water is the end result of a barley wash
operation which possibly introduces excessive bacteria counts to the
water. A high chlorine feed is thus needed to eliminate the bacteria.
These data are supported by the 1979 average chlorine concentration of
0.5 mg/1 (Table 2-1). Residual chlorine does have a tendency to dissi-
pate very rapidly and, as a result, prohibit? a fishery only immediately
below the effluent.
The major factors limiting a fishery in this section of stream
appear to be the fluctuating flows and the lack of instrearn and riparian
habitat. It is improbable any fish species would be capable of sustain-
ing itself through a complete life cycle in Clear Creek between Golden
and Youngfield Street. However, close attention should be paid to
prevent the degradation of downstream habitat by increased siltation
and decreased water quality.
At Youngfield Street, the stream channel becomes increasingly
confined with riparian vegetation immediately adjacent to the water's
edge, consisting of willows, cottonwood, and various grasses promoting
fish food (insects) and shading (cooling) of the water (Plate 2).
Instream substrate consists of cobble with some interstitial siltation.
Critically low flows persist through the entire section (4.7 miles) in
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2-66
PLATE 1
BELOW SLOUGH DITCH DIVERSION - RESTRICTED
FLOWS AND LACK OF RIPARIAN VEGETATION
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2-67
PLATE 2
PROSPECT PARK - OVERHANGING RIPARIAN
VEGETATION AND COBBLE SUBSTRATE
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2-68
both September and January due to the Slough Association diversion and
the rerouting of the Coors WWTP effluent to the Croke Canal,
respectively. Intermittent riffles and pools are found throughout this
section with the exception of the area impacted by 1-76 construction at
Wadsworth Boulevard which is expected to be temporary. In view of the
existing flow conditions, the pools in this segment would aid in the fall
and winter survival of the fish providing minimal eutrophication. Iron
and copper concentrations periodically exceeded EPA criteria at
Youngfield from mid-1976 to early 1977 (Section 2.4). No residual
chlorine concentration findings have been recorded for this section of
stream. Clear Creek between Youngfield Street and Wheat Ridge WWTP
appears to be habitable by most warm water species. The parameter which
would be the most limiting to a fishery in this section of stream would
be the fluctuating late summer flows and possible high concentrations of
iron and copper.
The overall quality of Clear Creek declines from the Wheat Ridge
WWTP downstream to the South Platte River. The water becomes more
turbid and the substrate consists mainly of silt and sparse cobble.
There is a limited number of very small (shallow) riffles and the ripar-
ian vegetation is stunted and in short supply. Accumulations of natural
and manmade litter are found throughout this section of the stream.
Marginally adequate flows occur during the fall throughout this section
of stream with the exception of the three miles of Clear Creek immedi-
ately above the South Platte River confluence. Where the water appears
to be stagnant, an organic scum covers the water's surface which is
possibly a result of leaching from nearby waste landfills (Plate 3).
Concentrations of ammonia (un-ionized) have exceeded EPA criteria
(of 0.02 mg/1) 300 meters downstream from the Wheat Ridge WWTP during
August and December of 1976; at Sheridan Street and Pecos Street during
June, August, and December of 1976; and at Broadway during February,
August, and December of 1976. At York Street this criterion'was exceeded
during September and October 1971; between November 1972 and March
1973; between September 1974 and March 1975; from May to July 1975;
from September 1975 to March 1976; from May 1976 to July 1976; from
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2-69
PLATE 3
BROADWAY - STAGNANT WATER WITH AN ORGANIC
SCUM COVERING THE SURFACE
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2-70
November 1976 to March 1977; from November 1977 to March 1978; during
September 1978 and from November 1978 to March 1979. Total residual
chlorine concentrations of 2.6 mg/1 were measured on 10 November 1976 in
the Wheat Ridge WWTP effluent and on 13 December 1976, 0.30 mg/1 was
measured in Clear Creek at Harlan Street by the Colordo Department of
Health. A total residual chlorine concentration of .20 mg/1 was detected
in Clear Creek at the Sheridan Street bridge which was presumably origi-
nating at the Clear Creek Valley and Arvada WWTPs.
Clear Creek from the Wheat Ridge plant to the South Platte River
appears to be the most unsuitable for a substantial fishery of any form
due to a combination of localized excessive concentrations of total
residual chlorine and unionized ammonia and restricted flows. Riparian
habitat and instrearn substrate is also of poor quality.
Maximum summer water temperatures from Golden to the Wheat Ridge
plant are marginally tolerable for cold water fish species based on EPA
storet data. Below the Wheat Ridge plant these temperatures approach
75°F which is generally not suitable for cold water fish species sur-
vival. Throughout the entire length of Clear Creek (Golden to the
South Platte River), the water temperatures are adequate for the survival
of warm water species and ideal for various Cyprinids (minnows). Dis-
solved oxygen concentrations range from 6.5 to 14.1 mg/1 which is well
within the range of tolerance for both cold and warm water species.
However, these dissolved oxygen concentrations may not reflect oxygen
sags during the night, especially below sewage treatment plants. Mea-
surements of pH throughout Clear Creek between Golden and the South
Platte River lie within the EPA criterion range for freshwater aquatic
life which is 6.5-9.0.
2.5.4 Chemical Stream Characteristics Specific to Aquatic Life
The only chemical parameters which are presently threatening the
quality of aquatic life in the lower segment of Clear Creek are un-
ionized ammonia and total residual chlorine. Ammonia has long been
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2-71
recognized as toxic Co fish (Belding, 1927; Grindley, 1946). The ammonia
toxicity to fish depends on Che portion of un-ionized ammonia in solution
which increases with temperature and pH. Un-ionized ammonia can also
reach toxic levels in highly alkaline waters. Although coarse fish such
as Carp survive longer in toxic solutions than salmonids, differences in
sensitivity among the species is probably small at prolonged exposure
(European Inland Fisheries Advisory Commission, 1970).
Laboratory experiments have demonstrated that lethal concentrations
at relatively short periods of exposure for a variety of fish species
ranges from 0.2 to 2.0 mg/1 NH,. The EPA criterion of 0.02 mg/1 NH, was
established to protect any aquatic organisms not yet examined for
sensitivity.
Total residual chlorine is acutely toxic to various species of fish
at different concentrations providing the fish are continually exposed.
Arthur (1972) found that fifty percent of the White Suckers, Largemouth
Bass, and Fathead Minnows perished after 96 hours of continuous exposure
to concentrations ranging from 0.09 to 0.30 mg/1 total residual chlorine.
Zillich (1972) found that fish held under continuous flow conditions at
Michigan treatment plants demonstrated that residual chlorine is not
extremely toxic for short periods of exposure. Fish were found to
survive in concentrations of chlorinated wastewater of 25 percent for 2
or 3 hours, 16 percent for 12 hours, and 7 percent for 24 hours (Zillich,
1972). Based on the following two findings, (1) total residual chlorine
rapidly dissipates after entering Che stream and (2) fish are known to
avoid toxic materials that are well below the concentrations required to
show toxic symptoms, it is apparent Chat only short segments of the
stream (below sewage treatment plants) are void of fish and that any
variations in the concentrations of total residual chlorine at the
effluent will probably not cause massive fish kills.
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2.6 AGRICULTURAL LANDS
An inventory was performed in July and August 1980 to identify
all agricultural lands in the Clear Creek Basin. June 1980 aerial
photography was analyzed and field checked. All agricultural parcels
exceeding approximately four acres were identified and classified by
type of agricultural activity.
Included in the inventory were lands classified as "oldfield,"
which are lands that were identified as having recently been cultivated,
but which have been abandoned and are not currently in production.
Fallow lands, by contrast, are lands not currently being cultivated,
but which are in rotation. Fallow lands were included in the unsegre-
gated cropland category. A description of each category of agricultural
lands is presented below. Agricultural lands are mapped in Figure 2-8.
Category
Unsegregated Cropland
Oldfield
Vegetable Cropland
Grains Cropland
Nurseries
Fruit Cropland
General Crazing
Improved Grazing
Unimproved Grazing
Hay Cropland (improved or
unimproved)
-Description
General category for fallow land and
land in cultivation, including for hay
and alfalfa, wheat, barley, grapes,
orchards, vegetables, etc., for which
no specific crop has been identified.
Recently abandoned croplands
Cultivated vegetables
Grains: wheat, barley, etc.
Trees, flowers, and plants, including
greenhouses
Cultivated fruits (apples, grapes,
etc.)
Lands used for grazing horses, cattle,
hogs, etc.
Fertilized, irrigated, or otherwise
"improved for grazing
Grazing lands not maintained; these
are not generally intensively grazed.
Includes alfalfa hay
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Agricultural parcels within the urbanized portions of the Clear
Creek Basin are generally quite small, with very few exceeding ten
acres. The primary uses of the urban areas parcels are horse grazing,
hay and alfalfa, nurseries, and truck gardens. It is unlikely that, with
the exception of nurseries, these parcels actually produce a profit for
the owners; most are cultivated and grazed for pleasure. Agricultural
parcels in the fringe areas (such as the area between Easley Road and
Mclntyre in Golden, western Adams County, and north of Arvada) are
generally larger and are devoted to a variety of agricultural uses. Many
of these parcels are farmed for profit.
Irrigation ditches service many of the parcels in the Clear Creek
Basin and its environs. The service areas of the irrigation ditches
that derive water from Clear Creek were determined through interviews
with officials of the several ditch companies. It is important to note
that the records of ditch companies on irrigation parcels are generally
incomplete. The service areas of the various ditch companies, shown in
Figure 2-8, include only the larger irrigated parcels. In the case of
several irrigation ditches (Welch, Agricultural, Slough, Reno and Juchem,
Colorado Agricultural, and Oulette Ditches), very general or no informa-
tion on service areas could be obtained. Therefore, assumptions had to
be made concerning the service areas of some ditches, such as the Slough
and Colorado Agricultural ditches. Approximately 4,352 acres of agri-
cultural land serviced by Clear Creek irrigation ditches were identified;
3,046 acres were located within the service areas of the Colorado
Agricultural and Clear Creek and Platte River Ditches.
A general agricultural service area is shown in Figure 2-9 for
lands serviced by Standley Reservoir and Farmers Highline Canal, which
passes just below the reservoir (Anderson, et al., 1976). These lands
are served primarily by Clear Creek Water. Also, the service areas of
Clear Creek and Platte River and Colorado Agricultural Ditches are shown
in Figure 2-10, extending to the north of Clear Creek Basin along the
South Platte River in Adams County.
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2-75
AGRICULTURAL SERVICE AREAS
B --W- T-A-W-&L-&Y-R E-&£-R-V- R
FIGURE 2-9
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2-77
Examination of land use plans of the several agencies with juris-
diction in the Clear Creek Basin indicates that much of the existing
agricultural land is planned to be developed for urban or park land uses.
The following is a discussion of local agencies and plans relevant to
agricultural land conversion within the basin. Figure 2-11 shows juris-
dictional boundaries.
Denver Regional Council of Governments (DRCOG). DRCOG is an
areawide planning agency responsible primarily for program implementation
and evaluation of grant applications for infrastructure investments in
the Denver metro region. Its influence on local land use planning
occurs through its review of infrastructure investment grant applica-
tions (primarily federal water and sewer system grant applications), but
DRCOG has no statutory land use policy implementation powers. DRCOG's
Regional Growth and Development Plan (RGDP) (1978, with subsequent
amendments) contains general policy guides for its grant application
review function. In this plan, general geographical areas are identi-
fied in which urban development is desirable, called "future service
areas." Generally, the City of Golden is included within the future
service area, as are Wheat Ridge and Arvada and most areas east of
Indiana Street. The DRCOG future service area boundary is depicted in
Figure 2-11. In areas outside (to the west of) the future service area
boundary, the RGDP states that "agriculture, forests, and other open
space uses should be the primary use of the land." Within the future
service area boundary, however, some areas are limited for development by
factors such as shrink-swell soils, floodplains, subsidence hazard areas,
and slope. The RGDP, however, is used as a general guideline; in many
areas within the future service area boundary, local governments have
planned for conservation uses, as is shown In Figure 2-11. Local plans
are generally more specific than the RGDP and in many cases are probably
better predictors of future land use.
City of Wheat Ridge. Clear Creek passes through Wheat Ridge for
approximately 4.5 miles, and Reno and Juchem, Swadley and Slough Ditches
service a few small agricultural parcels in the northwest part of the
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city. The city's Comprehensive Development Plan (City of Wheat Ridge,
no date) designates virtually the entire city for urban-type development,
except for greenbelts along Clear Creek and Lena Gulch and eight parks.
No areas are designated for agricultural preservation.
City of Arvada. Clear Creek traverses Arvada for about one mile,
and numerous agricultural ditches service lands within the city.
The Arvada Comprehensive Plan (City of Arvada, 1979) covers areas both
within the city and in the city's environs. Agricultural and conserva-
tion use designations are assigned to large areas of land southwest of
Standley Lake and near Leyden Lake, Tucker Lake, and Blunn Reservoir.
These areas are shown in Figure 2-11.
Jefferson County. Jefferson County's land use planning jurisdic-
tion covers all unincorporated county areas, within which many of the
agricultural ditches are located. The County Planning Department is
currently completing a new County Comprehensive Plan (Jefferson County
Planning Department, 1980) to replace its now-outdated plan. While this
plan does not specifically designate particular areas for development,
its preliminary land use suitability policies (not yet officially adopted
by the Jefferson County Board of County Commissioners) can be interpreted
through computer mapping to show areas that are most likely to undergo
urbanization by the year 2000. This analysis is based on the inherent
suitability of the land for development. Those areas with the highest
suitability are assumed to be most likely to urbanize (Blackburn, Groves,
and Dames & Moore, 1980). The policies set forth in the plan do not
prohibit floodplain development. Since such development will certainly
be highly restricted or prohibited, Figure 2-11 shows floodplain loca-
tions as well as areas rated likely to urbanize.
City of Westminster. The Farmer's Highline Canal services several
agricultural parcels within the City of Westminster. The city is formu-
lating a comprehensive land use plan, but no projection of its likely
ultimate policies can currently be made (Loving, 1980).
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City of Lakewood. The Agricultural Ditch and Rocky Mountain Ditch
traverse portions of northern Lakewood, but serve very few agricultural
parcels. The Lakewood Comprehensive Plan does not reserve any areas for
agricultural or conservation uses (Ospina, 1980).
Adams County. Much of the agricultural land serviced by agricultur-
al ditches from Clear Creek are located in Adams County, but only a small
portion are located within the Clear Creek Basin. The Adams County
Comprehensive Plan (Adams County Planning Commission, 1975) is a gener-
alized plan that designates the unincorporated area within the Clear
Creek Basin for development. However, much of this area is in a flood-
plain, has been farmed by families for decades, and is unlikely to be
developed (Perea, 1980).
2.7 USES FOR POTABLE WATER SUPPLY
Use of Clear Creek water for potable water supply occurs through
two general methods: (1) ditch diversions of surface flow into storage,
municipal water treatment plants, and potable storage and distribution
systems, and (2) individual withdrawal from shallow wells in alluvium for
home use as well as urban irrigation. Section 2.2 and Table 2-3 provide
a complete presentation of Clear Creek diversions by municipalities.
These data show the influence of Denver Water Board (DWB) supplies in the
near western suburban areas of Wheat Ridge, Lakewood, and Arvada.
Oulette Ditch diversions by Wheat Ridge are used raw for parks irriga-
tion, with virtually all potable supplies coming from the DWB Denver
system. Consolidated Mutual provides a portion of Lakewood's potable
supply from Clear Creek diversions chiefly through Agricultural and Lee,
Stewart and Eskins Ditches, but the bulk of their supplies come from the
Denver system. Arvada is planning to supply some new development areas
in its northwestern sector from Clear Creek diversions to newly con-
structed Blunn Reservoir but receives all but about one million gallons
per day from raw DWB supplies in Ralston Reservoir and the Denver system
at present. Also, Crestview Water and Sanitation District produces most
of its potable supply from Kershaw Ditch diversions.
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2-81
Other users of Clear Creek water for potable supplies are out-of-
basin municipalities to the north and northeast of Clear Creek Basin,
including Westminster, Northglenn, Thornton, and Broomfield. These
municipalities divert water through Standley Reservoir, as described
in Section 2.2. This trend is expected to continue in the future
with Northglenn and Thornton phasing out direct diversions through
Fisher, Colorado Agricultural, and Clear Creek and Platte River Ditches
in favor of storage rights in Standley Reservoir.
The other category of potable water use, alluvial wells, involves
over 700 domestic well supplies along the main steam of Clear Creek.
This estimate was derived by reviewing the master well list provided
by the State Engineers Office. Wells with recorded yields less than 50
gpm and less than 200 feet deep within the boundary of the Clear Creek
alluvium were assumed to be domestic or light industry. All wells with
individual ownership were assumed to be domestic. It is uncertain how
many of these wells are used for potable supply in addition to urban
irrigation. Two municipal supplies which come from wells in the alluvium
are owned by Wheat Ridge Mutual Water Company and Valley Water District.
An additional major well supply has been developed by Coors west of
Youngfield Street, but it is used primarily in brewing (Figure 2-2).
Wells used by Arvada for potable supply are deep, non-tributary wells.
2.8 RECREATION
The existing and proposed Clear Creek interceptors are located
in a corridor that is planned to serve as a central axis for a regional
recreation trails system. This trails system ultimately would provide
linkages to the many parks that currently serve the residents of the
Clear Creek Basin, as well as many of the parks planned for future
construction. A map of major recreational trails and parks is displayed
in Figure 2-12. The remainder of this section focuses on implementation
mechanisms, particularly funding, for trails plans.
Funding for implementation of recreational trails plans is available
from several sources. Local jurisdictions normally use general fund
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monies to perform comprehensive trails planning, and can apply to the
State Parks Board of the Parks and Outdoor Recreation Division of the
Colorado State Department of Natural Resources for state funding for
design, engineering, acquisition, and development expenses. However,
no funds have been available from the state for the past three years
(West, 1980).
Federal funding is available from the Department of Interior's
Heritage Conservation and Recreation Service (HCRS). HCRS Land and
Water Conservation funds are administered by the State Parks and
Recreation Division, and are available on a 50-50 matching grant basis.
The State Parks Board evaluates grant applications from local jurisdic-
tions after the applications have completed A-95 review by DRCOG, the
State Planning Division, and other agencies before forwarding applica-
tions to HCRS (West, 1980).
Federal funding for bikepaths is also available from the Federal
Highway Administration on an 80-20 matching basis. These funds are
administered by the Colorado State Highway Department. Grant applica-
tions are made by local jurisdictions to the State Highway Department,
undergo A-95 review, and are forwarded with recommendations to the
Federal Highways Administration. No funds have been appropriated by
Congress for 1980, however (Kloos, 1980).
Funding for recreation trails is also available under Section 201
of the Clean Water Act, administered by EPA. The Act provides for
funding for preparation of interceptor rights-of-way for recreational
trails but not for top-coating, as part of the overall 75 percent federal
grant.
In Jefferson County, funding for acquisition and development of
parks and trails is available through the Jefferson County Open Space
Program, which assesses a one-half cent county-wide sales tax. The funds
are used for planning, acquisition, development, and maintenance of parks
and trails, but not for major construction projects such as ballfields
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2-84
and swimming pools. The Jefferson County Open Space funds are allocated
to municipalities as well as to the unincorporated areas (Keith, 1980).
Numerous local jurisdictions are involved in the planning and
implementation of the planned trails and parks system. Each of the
cities in the Clear Creek Basin area and Adams County use general fund
monies and employ recreation and parks planners in the overall planning
process. Other agencies that play important roles in recreation imple-
mentation are the Denver Regional Council of Governments (DRCOG),
Jefferson County Open Space, the Parks and Outdoor Recreation Division of
the Colorado Department of Natural Resources, and the Colorado State
Highways Department. The roles of each jurisdiction are discussed
below.
DRCOG. The DRCOG Regional Growth and Development Plan (RGDP) (1978
as amended) designates the major existing and proposed trail systems and
park and recreation areas, as shown in Figure 2-12. The Clear Creek
trail is planned to extend from its junction with the Platte River trail
to the western border of Jefferson County, generally following Clear
Creek for its entire length. Most of the Clear Creek trail has been
completed between the Platte River and Youngfield Street. In the
DRCOG RGDP, the Clear Creek trail connects with trails along Leyden
and Ralson Creeks and the Platte River, affording hikers and bicyclists
access to all areas in the western Denver metropolitan area.
DRCOG's roles in recreation planning are primarily A-95 review
and intergovernmental coordination. As an A-95 review agency, DRCOG
evaluates federal and state grant proposals by local governments for
recreation funding, using the policies set forth in the RGDP as a general
guideline. Clear Creek Basin area trails and parks facilities identified
in the RGDP are depicted in Figure 2-12. DRCOG's coordination function
is largely ad hoc in nature, involving communication with jurisdictions
concerning funding opportunities and actions of other agencies. DRCOG
does not provide local jurisdictions with funding for recreation imple-
mentation but does in some cases provide recreation planning assistance.
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2-85
Jefferson County Open Space. Jefferson County Open Space is
funded through a one-half cent county-wide sales tax and is charged with
responsibility for land purchase and park planning and development in
Jefferson County. The Jefferson County Open Space Non-Motorized Recre-
ation Trails Plan (no date) calls for an extensive network of intercon-
necting trails which would connect all of the program's major parks.
The Clear Creek Trail west of Youngfield Avenue is designated as a
"Proposed Phase II" (design phase) trail in the Plan.
Parks and Outdoor Recreation Division, Colorado Department of
Natural Resources (PORD). PORD formulated a recreational trails plan in
1974 (Colorado Department of Natural Resources, 1974) but is currently
revising all recreation plans. The recreational trails plan, which is
in accord with the DRCOG RGDP (Figure 2-12) is used by PORD to evaluate
matching funding proposals from local jurisdictions. The western
reaches of the proposed Clear Creek trail are likely to be afforded only
a moderate priority once the new plan is completed since a primary
criteria for funding will probably be location near or in the central
Denver area (Mungan, 1980).
Colorado State Highway Department (CSHD). The CSHD works with local
jurisdictions in the planning and design of bikeways associated with
highway construction. Federal Highway Trust Fund moneys are avail-
able on a 90-10 matching basis. The 1-76 bikeway is being constructed
using these funds. As was previously noted, the CSHD also administers
highway funds provided by the Federal Highways Administration (Sabin,
1980).
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3-1
3.0 ALTERNATIVES
3.1 FACILITY PLAN ALTERNATIVES
As discussed in Section 1.0, the Facility Plan for Clear Creek
examined two basic configurations for the basin-wide treatment system,
the interceptor to the Central Plant, and various satellite plants.
Variations in treatment processes, plant sites, service areas, and flow
equalization systems yielded a preliminary list of eight alternatives
for examination in the Facility Plan. An iterative screening process
based on cost, engineering considerations, and implementation factors
reduced the list to three alternatives which were examined more closely
and compared on a present worth cost basis. Following preliminary
screening and public" involvement activities, two more alternatives were
added involving higher levels of treatment for wastewaters discharged or
reused in Clear Creek Basin. The Facility Plan concluded that the plan
to parallel the Clear Creek interceptor where necessary to transport flow
from the entire basin was the prefered alternative based on significant
cost savings.
3.2 PROPOSED ALTERNATIVE
The proposed alternative described in the facility plan involves
construction of a new interceptor parallel to the existing Clear Creek
interceptor. This pipe will be reinforced concrete, ranging in size from
33" at the Applewood/Pleasant View connection at Youngfield Street to 72"
at the siphon crossing of the South Platte River and inlet to the MDSDD
treatment plant.
Under this plan, the existing municipal treatment plants at Arvada,
Wheat Ridge, and Clear Creek Valley would continue to operate if eco-
nomically feasible or until discharge standards require substantial
rehabilitation or upgrading. However, the proposed alternative includes
eventual abandonment of these plants.
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3.3 TECHNICAL REPORT/FNSI ALTERNATIVE
During the planning process, numerous comments were made in favor
of maintaining a wastewater treatment plant in the basin for flow
augmentation and aesthetic purposes. In particular, the City of Golden
identified return flow obligations on Clear Creek which it would be
unable to satisfy without having its wastewater treated at an in-basin
plant and discharged to Clear Creek. Recently, Golden has announced its
intentions to associate with nearby Adolph Coors Company for treatment
and discharge of its wastewater to Clear Creek using the existing Coors
WWTP (Figure 2-1).
In view of this, the alternative evaluated in this study and sum-
marized in the FNSI includes both the Clear Creek Interceptor and the
Golden/Coors plant, In opting for treatment by Coors, Golden has advised
MDSDD of its desire to sever ties with MDSDD (Goudge, 1980). Although
the status of Golden's request is still uncertain due to MDSDD1s respon-
sibilities under State law (CRS Title 32, Part 5; 32-4-515) in granting
such a request, this study assumes that both the Clear Creek Interceptor
and the Golden/Coors plant are included in the alternative or proposed
project for review. The Golden/Coors plant will be locally funded,
however, without federal participation.
The Clear Creek Interceptor is described in Section 3.2 above. The
Golden/Coors plant will involve conversion of Coor's existing process
WWTP (see Section 2.1) for use in treatment of municipal wastewater.
The activated sludge plant has hydraulic capacity for 9.0 MGD average
day flow, but has capacity for much greater organic loading than will be
exerted by the largely domestic wastewater contributed by Golden and
Coors (McNeill, 1980a).
The plant will receive a loading of about 2.15 MGD from Golden and
Coors when it is converted in 1981 or 1982. Average flow in the year
2000 is expected to be about 3.00 MGD (Wheeler and Associates and Wright-
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3-3
Mclaughlin Engineers, 1974; MDSDD, 1980), far below plant capacity. The
plant is designed to provide high quality secondard treatment (BOD/TSS of
20-30 mg/1), but with greatly reduced loadings, it may be possible
to achieve some degree of ammonia conversion to nitrate.
Impact assessment for any other alternative configuration was beyond
the scope of this study.
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4-1
4.0 IMPACTS
In this section, the basic flow analysis approach applied to
existing conditions in Section 2.0 is extended to predict streamflow
conditions in the year 2000. Besides effects of the project on stream-
flow, future changes in diversion patterns are factored into the
analysis to produce as realistic a picture of future conditions as
possible. The impact analyses for Water Quality, Water Rights,
Aquatic/Fisheries, and Agricultural Lands follow from and utilize the
results of this analysis.
Pre-1967 conditions are also discussed and analyzed in this section
to provide insight into the effects of the original Clear Creek inter-
ceptor (operable in 1967) on streamflows.
4.1 WASTEWATER TREATMENT
4.1.1 Facilities
In the year 2000, wastewater treatment facilities operating in the
Clear Creek Basin will include the existing interceptor and proposed
project (Section 3.3), the Coors process wastewater plant, and the
Northwest Lakewood primary plant, which discharges to the existing
interceptor. In addition, the three existing municipal secondary
plants—Arvada, Wheat Ridge, and Clear Creek Valley—which discharge
effluents to Clear Creek may be operating. Total discharges to Clear
Creek will vary from 9.5 MGD to 15.0 MGD and discharges to the Clear
Creek Interceptor from 21.3 MGD to 26.8 MGD, depending on the status of
the existing in-basin municipal plants. The total of Clear Creek Basin
wastewater flows will be 36.3 MGD.
4.1.2 Fate of In-Basin Municipal Plants
The Clear Creek Interceptor pre-design includes capacity sufficient
to take all wastewaters now treated at the Arvada, Wheat Ridge, and Clear
Creek Valley (In-Basin) WWTP's. The reasoning for providing this excess
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4-2
capacity was the Facility Plan (CH2M Hill, 1977) cost-effectiveness
analysis, which showed the interceptor to be less costly compared to new
in-basin treatment plants. Since all the In-Basin WWTP's are at least 20
years old, it was assumed they will need replacement or extensive
refurbishment during the planning period, the costs of which will be high
compared to abandonment and use of the MDSDD interceptor.
Streamflow maintenance benefits of the In-Basin WWTP's were
considered to be outweighed by cost considerations in the Facility Plan
analysis. These streamflow effects are dealt with in detail in the
following sections.
Wastewater reuse was only considered for the regional in-basin
plants included in the Facility Plan alternative analysis. MDSDD recom-
mended that additional planning monies be made available so that govern-
mental units which operate existing In-Basin WWTP's can investigate the
potentials for continued operation or upgrading and effluent reuse (CH2M
Hill, 1977). To date, no additional facilities planning activities have
been initiated through MDSDD, although interest has been expressed by
Clear Creek Valley Water and Sanitation District and the City of Arvada
has made a request for funding priority directly to EPA.
A preliminary reclamation study was prepared for Arvada (Wright-
Mclaughlin Engineers, 1979) which identified about one MGD of non-
tributary well water which returns to Clear Creek at the Arvada WWTP and
could be reused for urban irrigation or discharged to Clear Creek and
exchanged for additional direct flow diversions from Clear Creek. No
action has been taken on this proposal by Arvada to date.
The proposed in-stream water quality standards for Clear Creek
(Colorado Department of Health, 1980) will have an important bearing on
all Clear Creek Basin wastewater management activities, including the
Golden/Coors and Coors process waste plants. These standards, described
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4-3
in more detail in Section 4.4, are more stringent than present standards.
Proposed standards would require upgrading of the existing In-Basin
WWTP's for nitrogen control as a minimum. Exact calculations of new
effluent limitations will be the responsibility of DRCOG, once the
standards are approved. The effect of upgrading requirements would
probably be to assure closure of the In-Basin WWTP's; the Golden/Coors
plant (converted existing process waste plant) will probably require
upgrading prior to initial use for municipal wastewater treatment and
discharge to Clear Creek in 1981 or 1982. The best opportunity for
continued operation of the In-Basin WWTP's would be in schemes involving
year-round diversion for reuse and no discharge to Clear Creek.
4.1.3 Reuse of MOSDD Central Plant Effluent
By the year 2000, as noted in Section 4.1.1, as much as 74 percent
or 26.8 MGD of Clear Creek Basin wastewater will be treated at the MDSDD
Central Plant. A large portion of MDSDD plant flows including those from
Clear Creek Basin originate from trans-mountain water supplies provided
by the Denver Water Board (DWB). DWB has plans for reuse of about 100
MGD of trans-mountain sewage return flow in its potable water system by
about 1995. This will involve construction of high technology reclama-
tion facilities near the MDSDD Central Plant, including a 1 MGD demon-
stration plant operable by about 1985.
4.2 DIVERSIONS AND WATER RIGHTS
4.2.1 Diversion Records
An operations study was performed, using data for the water year
1977, to see what effect the project might have on ditch diversions
within the Clear Creek basin. The year 1977 was selected as the study
year because it is the lowest streamflow year for which a complete
set of discharge records, diversion records and call records are avail-
able. The year 1977 is the third lowest streamflow year on record with
lower flows recorded in 1954 and 1963. The 1977 diversion records for
each of the 25 active ditches downstream of and including the Welch Ditch
headgate are summarized in Table 2-7. Most diversions do not begin until
April or May and cease during the month of November.
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4.2.2 Operations Scudy Parameters
Quantification of streamflow changes which are expected to occur
because of changes in sewage effluent return patterns are discussed
in section 4.3 of this report. This section discusses the assumptions
that are used in identifying the ditches which are benefited or injured
and in quantifying the amount of benefit or injury. Several of the
assumptions are applicable to all months while some only apply to
specific months. The specific months of water year 1977 for which the
operations study was developed are January, March, May, August, September
and October.
The three general assumptions made are: 1) that diversions and
streamflows would be the same in a dry year in the future as they
were in 1977; 2) that any flow changes attributable to the various
proposed and decreed augmentation plans would be minor; 3) that the Croke
Canal will divert all water that is legally available under its 1902
priority whenever the water is physically available at its headgate. It
is not known how long the first assumption may remain valid in that Clear
Creek is currently in the process of changing from a source of supply for
primarily agricultural interests to a source of supply for primarily
municipal and industrial interests. It is also possible that, in 1977,
municipal and industrial interests were not actively using water rights
which they have purchased and plan on using in the future. The extent of
water rights being held inactive is not known and therefore any potential
effect on streamflow conditions resulting from the future use of such
rights cannot be quantified at this time. However, to the extent that
the first assumption remains valid, the second and third assumptions
should be accurate. Assumptions applicable to each of the individual
months are as follows.
January and March
The same conditions exist on the creek for both of these months;
therefore, they will be discussed simultaneously. In both months
the Croke Canal is diverting water for eventual storage in Standley
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4-5
Reservoir. When the Croke Canal is diverting, it generally takes the
entire streamflow, thereby drying up the stream immediately below the
canal headgate. The only water being diverted downstream is at the
Fisher Ditch headgate. Since the creek is dry directly below the
Croke Canal, the Fisher Ditch is completely satisfied by return flows.
Also, since the water diverted at the Fisher Ditch headgate appears to
be an old agricultural right that is being used by Public Service
Company for its Cherokee Plant, there is a possibility that this is an
undecreed use and therefore the Fisher Ditch is not able to call out
the Croke Canal.
Thus, any additional flows introduced to the creek upstream of
the Croke will be diverted by the Canal. Any decrease in streamflows
below the headgate of the Croke Canal will be borne by either the creek
or by the Fisher Ditch. As stated earlier, it is doubtful that the
Fisher Ditch could pass the effect of any injury sustained to any other
ditch.
May
In May there were six days when the Clear Creek and Platte River
Ditch had its 11-1-1861 call on the creek, eleven days when the Colorado
Agricultural Ditch had its 11-5-1863 call on the creek, and three days
when the Colorado Agricultural Ditch had its 3-5-1867 call on the creek.
During the rest of the month the calls emanated from ditches on the South
Platte River. On most of the days when the South Platte Ditches called
for water, there was water flowing past the Clear Creek and Platte
River Ditch headgate. Also on all the days when the Colorado
Agricultural Ditch calls and the Clear Creek and Platte River Ditch calls
were on the river, there were several other upstream ditches diverting on
more junior priorities.
Based on the above conditions, the following assumptions are made.
Whenever one of the ditches on the South Platte River is the only call on
the creek, any changes in streamflow on Clear Creek will accrue to the
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South Platte River. Whenever the calling ditch is the Colorado
Agricultural Ditch or the Clear Creek and Flatte River Ditch, and there
is a net increase in streamflow that increase will accrue to the calling
ditch first and possibly the South Platte River. Whenever the calling
ditch is the Colorado Agricultural Ditch or the Clear Creek and Platte
River Ditch and there is a net decrease in streamflow, that decrease will
accrue to one of the upstream diverters as a result of that diverter
being required to reduce his diversions in order to satisfy the need of
the calling ditch. It cannot be determined who the decrease might accrue
to unless the diversion records of all of the diverters in the entire
Clear Creek Basin are examined.
August
During the month of August the Clear Creek and Platte River Ditch's
11-1-1861 call was on the river for 26 days; the Fisher Ditch's 6-29-1861
call was on the river for three days; and the Swadley Ditch's (part of
the Slough Association) 5-14-1861 call was on the river for seven days.
There were times when both the Fisher Ditch and the Clear Creek and
Platte River Ditch were calling and there were other times when both the
Swadley Ditch and the Clear Creek and Platte River Ditch were calling.
Based on the above conditions, the following assumptions are made.
Whenever the Clear Creek and Platte River call is the only call on the
creek below the proposed Golden/Coors plant, all changes in stream-
flow will accrue to the Clear Creek and Platte River Ditch. Whenever
the Fisher call is the only call on the creek below the proposed Coors/
Golden Plant and when both the Fisher call and the Clear Creek and Platte
River call are on the river simultaneously, all changes in streamflow
will accrue to the Fisher Ditch. Whenever the Swadley call is the only
call on the creek below the proposed Golden/Coors Plant or when the
Swadley call and the Clear Creek and Platte River call are being exer-
cised simultaneously, all increases in streamflow will accrue to the
Swadley Ditch Slough Association until the diversions total 11.077 cfs.
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4-7
All of the remaining increases in streamflow will then accrue to the
Fisher Ditch and possibly the Clear Creek and Platte River Ditch. All
decreases in streamflow below the Slough Association Ditch headgate will
accrue to the Fisher Ditch and possibly the Clear Creek and Platte River
Ditch.
September
During the month of September the Swadley Ditch's 5-14-1861 call was
on the creek for 22 days while the Fisher Ditch's 6-19-1861 call was on
the creek for eight days. Based on the above conditions, the following
assumptions are made. Whenever the Swadley call is the only call on the
creek below the proposed Golden/Coors Plant, all increases in streamflow
will accrue to the Swadley Ditch until the Slough Association diversions
total 11.077 cfs. All of the remaining increases in streamflow will then
accrue to the Fisher Ditch and possibly the Clear Creek and Platte River
Ditch. All decreases in streamflow below the Slough Association Ditch
headgate will accrue to the Fisher Ditch and possibly the Clear Creek and
Platte River Ditch. Whenever the Fisher Ditch call is the only call on
the creek below the proposed Golden/Coors Plant, all changes in stream-
flow will accrue to the Fisher Ditch and possibly the Clear Creek and
Platte River Ditch.
October
During the month of October the Fisher Ditch's 5-14-1861 call was on
the creek throughout the month. Based on this condition, the following
assumption was made. Whenever the Fisher Ditch call is the only call on
the creek below the proposed Golden/Coors Plant, all changes in stream-
flow will accrue to the Fisher Ditch and possibly the Clear Creek and
Platte River Ditch.
4.2.3 Impacts Summary
Impacts on water rights and diversions are summarized in this
section for the three general flow regime periods—winter, runoff
season, and late summer/fall irrigation season. Streamflow and
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4-8
diversion impacts for the low flow irrigation season are quantified in
Section 4.3.
Croke Canal benefits from increases in direct sewage discharges
from the Golden/Coors plant in the winter. Although depletions would
accrue to Fisher Ditch in winter, calculations based on January 1977
flows (Table 2-4 in Section 2.3) show adequate streamflow for satisfying
Fisher Ditch needs, even if the in-basin WWTPs close.
The situations for the runoff and later summer/fall irrigation
seasons are shown in Table 4-1. Fisher and Slough Association Ditch
diversions are affected in the later irrigation season. Changes in WWTP
discharges will affect Colorado Agricultural and Clear Creek and Platte
River Ditch (CCPRD) diversions in both the runoff and late summer/fall
irrigation seasons. Substantial adverse impacts will accrue to the
Fisher Ditch, Colorado Agricultural Ditch, and CCPRD as a result of the
project if the Wheat Ridge, Arvada, and Clear Creek Valley WWTPs close
down.
4.3 STREAMFLOWS
4.3.1 Methodology
To evaluate the impacts of the proposed MDSDD interceptor on stream-
flows, five conditions are considered. Condition 1 is the existing
condition, where 1975 was intended to be the base year. However, as
mentioned previously, available data was insufficient to analyze 1975 (an
average year), and therefore 1977 (a dry year) was analyzed on a monthly
basis. Although the specific flow amounts differ in a dry versus an
average year, the flow regimes are similar. That is, wastewater inflows
are essentially the same, and reaches of the stream that undergo low
flows in a dry year also undergo low flows in an average year. There-
fore, except for specific flow quantities, it is felt that either 1975 or
1977 may be considered the base year. The flow quantities that change
are the amounts of water taken from the stream, and in general the
conditions downstream of the headgates are the same in a dry versus
average year.
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TABLE 4-1
EFFECTS OF PROJECT ON WATER RIGHTS
Season Affected
Affected Ditch
Slough Association
Fisher
Lower Clear Creek and
Platte River
Colorado Agricultural
Runoff
Late Irrigation
Conditions
2 & 4
o
o
Conditions
3 & 5
o
o
_*
_*
Conditions
2 & 4
Conditions
3 & 5
_*
_*
Notes: See Section 4.3 for definitions of conditions
+ = diversions increase due to project
- = diversions decrease due to project
o = no effect
* = significant impact
Condition 1 = Present situation, 1975/1977.
Condition 2 = Present conditions with project in place and existing
in-basin plants open.
Condition 3 = Present conditions with project and in-baein plants closed.
Condition 4 = Year 2000 with project and In-basin plants open.
Condition 5 = Year 2000 with project and in-basln plants closed.
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For conditions 2 through 5, the Golden/Coors plant is assumed to
be in operation. Thus the combined domestic wastewater of Coors and
Golden is treated and discharged to Clear Creek. Coors' process water
will be discussed as a different WWTP but will discharge in the same
location as the domestic wastewater.
With the above discussion implemented, condition 2 is the existing
situation with all WWTP's operating. Condition 3 is the existing situa-
tion with the Wheat Ridge, Clear Creek Valley and Arvada plants closed.
Condition 4 is the year 2000 with the plants open, while condition 5 is
the year 2000 with the plants closed. These conditions are also listed
in Table 4-1.
To project the year 2000 conditions, it was necessary to estimate
the future discharges of the WWTP's. MDSDD has estimated the Golden
discharge at 3,350 A-F (3.0 MGD) for the year 2000 (McNeill, 1980b). The
Wheat Ridge WWTP discharge will increase slightly to 2,850 A-F (2.5 MGD)
(Williams, 1980). Discharges from the Arvada WWTP were assumed to remain
constant at the 1977 level, 910 A-F (Adams, 1980). The Clear Creek
Valley WWTP has no information as yet as to future flows (Michna, 1980).
Therefore, we have assumed that the plant will continue at its present
capacity of 2,350 A-F (2.1 MGD). The Coors process water flows are
assumed to continue at their 1977 level of 4,030 A-F (3.6 MGD). In
actuality, Coors is anticipated to double production and thereby double
the amount of treated process water. However, we have assumed that they
will increase their demands on Clear Creek by an amount that balances the
increased wastewater discharge and therefore a net streamflow change of
zero occurs.
The effect of the proposed interceptor, with respect to both total
and native flows, can be analyzed on an annual basis for the whole of
Clear Creek without difficulty. The analysis is presented in Table 4-2.
The native flows were calculated on the basis of percentages presented in
the Leonard Rice (1978) water rights study. The Coors process water is
assumed to be 100 percent native (Jaquet, 1980).
-------
TABLE 4-2
ANNUAL CHANGES IN FLOW ON CLEAR CREEK WITH MDSDD INTERCEPTOR
AND GOLDEN/COORS PLANT*
TOTAL FLOWS
Discharges to Clear Creek
Colden/Coors
Coors
Wheat Ridge
Clear Creek Valley
Arvada
Total
Change from Condition 1
NATIVE FLOWS
Discharges to Clear Creek
Colden/Coors
Coors
Wheat Ridge
Clear Creek Valley
Arvada
Total
Change from Condition 1
EXISTING
SITUATION
(1975)
(all values
0
4,000
2,560
1,460
970
8,990
0
0
4,000
0
0
0
4,000
0
CONDITION 2
1975 PLANTS
OPEN
In acre— feet
2,400
4,000
2,560
1,460
970
11,390
+2,400
2,330
4,000
0
0
0
6j330
+2,330
CONDITION 3
1975 PLANTS
CLOSED
per year)
2,400
4,000
0
0
0
6,400
-2,590
2,330
4,000
0
0
0
6,330
+2,330
CONDITION 4
2000 PLANTS
OPEN
3,350
4,000
2,850
2,350
910
13,460
+4,470
2,850
4,000
60
190
130
1*230
+3,230
CONDITION 5
2000 PLANTS
CLOSED
3,350
4,000
0
0
0
7,350
-1,640
2,850
4,000
0
0
0
6^850
+2,850
r
*1975 is used as the base year In this table only in order to maintain consistency with
the previous Leonard Rice Report (1978).
-------
4-12
With respect to Clear Creek as a whole, the MDSDD interceptor, in
combination with the Golden/Coors plant, increases the amount of native
water in the creek. However, if the existing WWTP's are closed (condi-
tions 3 and 5 in Table 4-2), the total flow available is reduced by 2,590
A-F and 1,640 A-F for the years 1975 and 2000, respectively.
The changes in flow that are shown on Table 4-2 do not affect all
portions of Clear Creek. The locations of points of discharge are not
the same under all conditions and the changes in flow are subject
to the complex set of water rights that exist on Clear Creek. To iden-
tify specific reaches that either gain or lose flows, the creek must
be examined in more detail. We have analyzed winter, late summer/fall
irrigation, and runoff months.
4.3.2 Winter Streamflow
During the winter season (November through March), the effects of
the MDSDD interceptor and Golden/Coors plant are fairly straightforward.
Figure 2-3 and Table 2-4 characterize the flows for January, a typical
winter month. The Croke Canal will divert all of the increase in flows
that result from the Golden/Coors plant. If the existing WWTP's remain
open (conditions 2 and 4) there would be no effect on Clear Creek; the
existing (1977) winter conditions would continue. Under conditions 3
and 5 with the WWTP's closed, there would be critical low flows (less
than 3 cfs) from the Croke Canal to Ralston Creek. From Ralston Creek to
the Fisher Ditch the flow in Clear Creek would exceed the critical level,
but the flow would be reduced from 1977 levels by the wastewater with-
held, about 440 A-F per month. The Fisher Ditch would reduce the flow to
below the critical level. Downstream of the Fisher Ditch the natural
gains would again increase the flow to above critical.
4.3.3 Late Irrigation Season Streamflow
The impacts during the summer season are more complex than during
the winter. The allocation of Clear Creek water is dependent on the
water rights calls on the river, which vary on a daily basis during the
irrigation season. To estimate the impacts for the non-runoff summer
-------
4-13
months, we have performed an analysis of the month of September,
projecting the streamflow of 1977 to the year 2000 (see Figures 4-1
through 4-4).
Table 4-3 presents the estimated changes in streamflow from con-
dition 1 (existing condition) that may occur for conditions 2 through 5.
If the existing plants remain open, Clear Creek flows would be increased
above the Clear Creek and Platte River Ditch due to the flow addition of
Golden's wastewater. Under conditions 3 and 5, with the plants closed,
there would be an increase in flows upstream of the plants, but a
decrease In flows would occur between the plants and the Clear Creek and
Platte River Ditch.
Impacts to diversion ditches associated with these changes in
flows are based on the 1977 calls as discussed in Section 4-2; the Slough
Association will absorb some but not all of the increased streamflows
resulting from the Golden/Coors plant. The Fisher Ditch and the Clear
Creek and Platte River Ditch will increase their diversions slightly if
the WWTP's remain open. If, however, the plants close as in conditions 3
and 5, the amounts of water available .to these two ditches will decrease.
The effects of the various conditions on the affected ditches are
presented in Table 4-4.
4.3.4 Runoff Season Streamflow
The month of May, a runoff month, was analyzed on a qualitative
basis assuming that the pattern of calls in the year 2000 would be
similar to those of 1977. Increases or decreases in streamflow associat-
ed with the project will accrue totally to the South Platte River during
about 11 days of the month. Increases in flow during the total of 20
days the Clear Creek and Platte River Ditch and Colorado Agricultural
Ditch (CAD) have their calls on the creek will accrue to these ditches,
with a portion of the increase accruing to the South Platte River if the
total needs of the CCPRD and CAD are exceeded by the increase. Decreases
in streamflow during those same 20 days will accrue to upstream junior
ditches.
-------
PAGE NOT
AVAILABLE
DIGITALLY
-------
TABLE 4-3
ESTIMATED CHANGES IN STREAM FLOW FROM EXISTING CONDITIONS
(For Month of September)
STREAM
MILE
13.42
12.22
7.50
6.70
6.33
5.28
3.03
0
ACRE FEET/CFS
STREAM REACH
Goers/Golden WWTP
TO
Slough Association
TO
Wheat Ridge WWTP
TO
(Hear Creek Val WWTP
TO
Arvada WWTP
TO
y
Fisher Ditch
TO
Clear Creek & Platte R. D.
TO
Natte KLver
CONDITION 2
197.8/3.32
78.0/1.31
78.0/1.31
78.0/1.31
78.0/1.31
0
0
CONDITION 3
197.8 / 3.32
84.6 / 1.42
(-119. 4) / (-2. 01)
(-266.5)/(-4.49)
(-340.9)/(-5.74)
(-162.0)/(-2.72)
0
CONDITION 4
275 M.62
117.7/1.98
148.1/2.49
194.2/3.27
194.2/3.27
76.5/1.28
0
CONDITION 5
275 / 4.62
125.8 / 2.12
(- 78. 2) /(-I. 32)
(-225.3)/(-3.79) £
(-299.7)/(-5.05)
(-162.0)/(-2.72)
0
NOTE: Conditions upstream of stream mile 13.42 is assumed to remain approximately as present conditions.
-------
TABLE 4-4
ESTIMATED CHANGE IN DIVERSIONS
FOR MONTH OF SEPTEMBER
D LTCI1
Slough
Association
Fisher Ditch
Ciear Creek and
South Platte
River Ditcii
CONDITION 1
(Present)
534.6
N
316.8
378.2
CONDITION 2
Diversion Change
654.4 119.8
394.8 78.0
378.2 0
CONDITION 3
Diversion Change
647.8 113.2
137.9 -178.9
216.5 -161.7
CONDITION 4
Diversion Change
691.9 157.3
434.5 117.7
454.7 + 76.5
CONDITION 5
Diversion Change
683.8 +149.2
179.1 -137.7
216.6 -161.6
NOTES:
1) All values shown are in acre feet
2) Changes indicated are from present condition (Condition 1)
3) All other diversions on the stream are considered to divert flows as in present conditions
-------
4-20
During May it is unlikely that the level of flow would be below
the critical low flow level of 3 cfs or 180 A-F per month. The flow
level would vary in relation to the base conditions, but, even in a dry
year, the flow would probably remain above about 900 A-F per month
(15 cfs) throughout the length of Clear Creek.
4.4 WATER QUALITY IMPACTS
4.4.1 General Considerations
The recommended alternative described in Chapter 3, including
abandonment of existing in-basin WWTP's, will result in diverse impacts
on Clear Creek water quality. Several of these impacts are a result of
urban development and land use changes rather than of the selected
alternative. The interrelationships between land use, stream flow,
aquatic habitat, and water quality provide numerous variables for consid-
eration. The impacts of the alternative on water quality are discussed
in light of these variables in the following sections.
4.4.2 Issues Not Specific to the Chosen Alternative
Certain impacts on water quality associated with this project
are not specific to the chosen alternative. Impacts associated with
land use, mine drainage, abandoned landfills, and DRCOG's 208 Non-
Point Source Program fall within this category and are discussed below.
Land Use
Development of the Clear Creek Basin has been an accepted part of
all previous studies. Conversion of vacant, grazing, or agricultural
land to residential, commercial, or industrial uses results in changes
in the degree and types of pollutants contributed by storm runoff.
Land use changes have been examined in previous studies and in other
sections of this report. Water quality impacts of these changes have
been estimated in the DRCOG modeling studies performed as part of the
Water Quality Management Program. Increases in ammonia, nitrate,
phosphrous, fecal coliforms and total dissolved solids were anticipated.
-------
4-21
As the urban area expands into vacant or agricultural land,'natural
drainage systems will be replaced by ditches (usually following roads)
and storm sewers. As has occurred in the past, these storm drainage
systems will concentrate the storm water discharge into Clear Creek or
its tributaries. This man-made system may be significantly different
from the natural drainage patterns both in flow sequence and discharge
locations. Thus, not only will the land use changes affect the types and
magnitude of pollutants discharged, but the locations of in-stream water
quality impacts of urban runoff will be affected.
Mine Drainage
A major premise of the Clear Creek Facility Plan has been the
presence of significant metals concentrations from upstream mine drain-
ages (CH.M Hill, 1977). Studies currently underway by the Colorado
Mined Land Reclamation Board are expected to produce significant water
quality improvements (Holm, 1980). Noteworthy projects under consid-
eration include possible treatment and metals recovery from the Argo Mine
drainage and the routing of North Clear Creek flow through Central City
and Blackhawk to avoid mine tailings. It is believed that the completion
of these two projects, which is anticipated within the next five years,
will reduce the metals concentration in the upper main stem of Clear
Creek to the point where a cold water fishery can be re-established. A
reduction downstream in the study area is also anticipated.
However, it is also expected that additional mining will take place
and existing mines will be reopened in the future (Holm, 1980).
Historically, enforcement of discharge permit requirements for mining
operations is reported to have been extremely lax. In addition, inactive
mine operations are not required to comply with discharge standards and
discharges from these mines occur uncontrolled. Thus, unless enforcement
acivities are expanded to provide control of inactive mines and better
monitoring of operating facilities, any upstream water quality improve-
ments achieved in the next few years will probably be eclipsed by new
discharges.
-------
4-22
Landfills
The possibility of pollutant leaching from landfills has been
studied at a site adjacent to Clear Creek in Adams County (Fox and
Assoc., Inc., 1974). Results from the initial sampling, during the
spring, summer, and fall of 1974, show minor pollutant leaching. Sub-
sequent samples taken in 1976 and 1977 show increases in concentrations
of calcium, magnesium, sodium, chloride, sulfate, ammonia, and free
carbon dioxide. No measure of ground water flow through the site
is available, but the methods of filling and compaction were expected
to minimize this movement.
Given the large number of abandoned landfills adjacent to Clear
Creek and concentrated between Sheridan Boulevard and Broadway, as
shown in Figure 2-7, continued leaching of pollutants is likely.
The long-term impact of these pollutants is difficult to quantify;
however, a decrease in values with time is expected as the wastes
stabilize. Furthermore, construction activities on the 1-76 and Clear
Creek Interceptor routes crossing this area may require removal of some
of the old dumps.
Non-Point Source Program
In the 208 Water Quality Management Plan for the metro Denver
area, DRCOG established the Non Point Source Program to reduce the
magnitude of non-point source pollution in the area. Specific measures
to be implemented at present are, for the most part, non-structural
and funded only from existing governmental maintenance budgets. However,
ongoing studies by DRCOG continue to explore the effectiveness and
adequacy of non-point source controls, and ongoing control projects
are planned to reduce pollutants from storm runoff.
4.4.3 Issues Specific To The Chosen Alternative
The timely full utilization of the proposed Clear Creek Interceptor
is, in part, dependent upon the abandonment of facilities now operating
in the basin. The continued operation of these plants is dependent upon
-------
4-23
the classification of Clear Creek by the state and the subsequent
discharge standards imposed.
Water Quality Standards
The Colorado Water Quality Commission is considering adjusting the
water quality standards for Clear Creek based on standards proposed by
the Colorado Department of Health. These standards provide for a
warm water fishery on Clear Creek below Golden and stringent requirements
for protection of public water supplies.
The Adolph Coors Company has proposed an alternative set of
standards which do not make provisions for a warm water fishery. The
Coors standards are less stringent than the Colorado Department of Health
standards and propose the division of Clear Creek segments at Wadsworth
Boulevard rather than Youngfield Street. Differences in the two proposed
standards are noted for ammonia, residual chlorine, cadmium, copper,
lead, iron, manganese and zinc. These two sets of standards are present-
ed in Tables 4-5 and 4-6. Other governmental units, such as the CDW,
and interested parties have prepared alternative proposals to the
Department of Health proposed standards, but not in the level of detail
of standards prepared by Coors.
The standard selected will have a pronounced effect on water
quality, since subsequent discharge permits will be based on these
standards and on low flow values.
Low Flows
Section 4.3 discusses low flow values for Clear Creek, however it
should be noted that original low flow estimates used in determining
discharge standards were significantly higher than actual low flows.
When coupled with the existing stream classification in the wasteload
allocation, the resulting discharge requirements for a given discharger
were high (Black and Veatch and DRCOG,, 1974). Thus existing discharge
requirements would require revision to account for more realistic low
-------
4-24
TABLE 4-5
Proposed Water Quality Standards
Colorado Department of Health
Clear Creek
Parameter
Mainstream from Golden
to Youngfield Street
Mainstream from
Youngfield Street
to So. Platte River
Dissolved Oxygen
PH
Fecal Coliforms,per 100ml
Ammonia (unionized) (NH_)
Residual Chlorine (C12)
Cyanide (free)
Sulfur (asH2S undis.)
Sulfate (S04)
Boron
Nitrite (N02)
Nitrate (NO )
Chloride (Cl)
Arsenic (As)
Cadmium (Cd)
Chromium (tri)
Chromium (hex)
Copper (Cu)
Lead (Pb)
Iron (Fe.sol.)
Iron (Fe.tot.)
Manganese (Mn.sol.)
Manganese (Mn,tot.)
Mercury (Hg)
Nickel (Ni)
Selenium (Se)
Silver (Ag)
Zinc (Zn)
1
5.0
6.5-9.0
2000
0.10
0.003
0.005
0.002
250.0
0.75
0.5
10.0
250.0
0.05
0.001
0.05
0.025
0.024
0.025
0.3
1.2
0.05
1.2
0.00005
0.1
0.01
0.0001
0.150
/
5.0
6.5-9.0
2000
0.06
0.003
0.005
0.002
0.75
0.5
0.05
0.001
0.05
0.025
0.024
0.025
0
1.2
-
1.2
0.00005
0.1
0.01
0.0001
0.150
-------
4-25
TABLE 4-6
Proposed Water Quality Standards
Adolph Coors Company
Clear Creek
Parameter
Mainstream from Golden
to Wadsworth Boulevard
Mainstream from
Wadsworth Boulevard
to So. Platte River
Dissolved Oxygen
pH
Fecal Coliforms,per 100ml
Ammonia (unionized) (NH.)
Residual Chlorine (Cl«)
Cyanide (free)
Sulfur (as H.S,undis.)
Sulfate (S04)
Boron
Nitrite (NO )
Nitrate (N03)
Chloride (Cl)
Arsenic (As )
Cadmium (Cd)
Chromium (tri)
Chromium (hex)
Copper (Cu)
Lead (Pb)
Iron (Fe,sol.)
Iron (Fe,tot.)
Manganese (Mn.sol.)
Manganese (Mn.tot.)
Mercury (Hg)
Nickel (Ni)
Selenium (Se)
Silver (Ag)
Zinc (Zn)
1
5.0
6.5-9.0
2000
0.28
0.31
0.005
0.002
250.0
0.75
0.5
10.0
250.0
0.05
0.003
0.05
0.025
0.14
0.12
0.3
3.5
0.05
1.4
0.00005
0.1
0.05
0.0001 .
0.90
5.0
6.5-9.0
2000
1.12
0.003
0.005
0.002
0.75
0.5
•
0.05
0.003
0.05
0.032
0.16
0.05
-
2.6
-
2.5
0.00005
0.1
0.01
0.0001
0.70
All parameters expressed in mg/1 unless noted otherwise
-------
4-26
flow values shown in Section 2.3 and 4.3. Similarly, future discharge
requirements will probably be more stringent not only due to the stream
classification but due to the revised low flow values.
Water Quality Impacts
Since specific discharge standards are based on a given low flow and
the stream water quality classification, it follows that less stringent
water quality standards will result in less stringent discharge
requirements.
The selected alternative calls for the abandonment of the three
existing treatment plants discharging to Clear Creek. Stricter standards
will accelerate this abandonment, and less strict standards may postpone
it. In-stream water quality will be improved by the abandonment of these
plants, however stream flow in the reach below each plant may be
seriously reduced. The stricter standards would therefore hasten the
water quality improvement and flow depletion.
In turn, the abandonment of these plants will result in a higher
percentage of flow being contributed from non-point sources. The effect
on in-stream water quality will be a function of the relative quality of
the upstream flows and the non-point flows. Implementation of non-point
source controls will reduce this influence an as yet undetermined
amount.
The year 2000 critical low flow condition, described in Section
4.3, will extend from Croke Canal to Ralston Creek in the winter and
from the Slough Association Ditch (Youngfield Street) to the South Platte
River in the fall if the existing in-basin WWTP's close. The non-point
source contributions, expected to be concentrated below Kipling Street,
coincide with these critical low flow areas. Thus, during these low flow
periods, the water quality in Clear Creek below Kipling should approxi-
mate the quality of water from the non-point sources, notably urban
runoff and groundwater seepage.
-------
4-27
From April Co October, discharges from the Coors process wastewater
treatment plant and the Golden/Coors wastewater plant will provide a
significant portion of the flow in Clear Creek down to the Slough
Association diversion. Due to the addition of the domestic wastewater
effluent, nitrogen and phosphous concentrations will be increased in this
segment. The impact of these nutrients on stream quality will be a
function of the discharge standards, as discussed above.
4.5 AQUATIC/FISHERIES
4.5.1 Possible Areas of Habitat Loss - Short/Long Term
The initial impact to Clear Creek resulting from construction
activities associated with the expansion of the sewage interceptor
includes disturbing the benthic and riparian zones of the stream. The
points along Clear Creek where the proposed interceptor will either
intersect or approach the stream include the following: (1) 300 feet
east of Farfet Street, (2) 200 feet west of Garland Street, and (3) 200
feet west of Fecos. The interceptor will also intersect Ralston Creek
approximately 400 feet upstream from the Clear Creek confluence.
Actual construction will probably increase the suspended solids
downstream and, as a result, increase sedimentation. Long-term impacts
should be minimal providing stream banks are properly stabilized (i.e.,
revegetated and/or riprapped) immediately after construction activities
cease. This would minimize future erosion and sediment problems.
Little or no direct fish mortality is expected. Ritchie (1972)
found that physical damage to fish in waters with high suspended solids
is limited because fish are able to withstand high turbidities for
short periods. However, benthic macroinvertebrate populations may be
altered slightly due to the increased sedimentation downstream. Construc-
tion activities may inhibit populations of these invertebrates at and
immediately below each site, but recolonization should occur shortly
after construction. Barton (1977) found that invertebrates had quickly
-------
4-28
recolonized a new riffle area which was previously denuded and removed
during the construction of a highway culvert. Barton et al (1972) found
Chat invertebrates completely recolonized a denuded stream bottom six
months after highway construction activity in Utah. Based on the above
findings, any construction-related impacts, from the installation of
an additional interceptor pipe paralleling Clear Creek, are expected to
be short term and of very little consequence to the existing aquatic
life.
4.5.2 Future Importance of the Fishery
Until 1978, Clear Creek, below Golden, was not seriously considered
as a source for fishing recreation. In the past few years, as trans-
portation costs drastically increased, the Colorado Division of Wildlife
began scrutinizing this section of Clear Creek for its potential as a
municipal fishery. Along with maintaining the present population
status of the various species, the Colorado Division of Wildlife is
involved with the establishement of a Channel Catfish population through-
out lower Clear Creek (Woodling, 1980). Channel Catfish have been widely
accepted as a game fish throughout the central and southern United
States, and more recently have gained popularity among some avid cold-
water anglers further west. The Channel Catfish tolerates turbid water
and, being an omnivore, appears to be well suited for lower Clear Creek
habitation. An additional future consideration for fishery potential
includes the advocation, by the Division of Wildlife, of the Creek Chub
as an acceptable panfish. The Creek Chub is well adapted to streams and
is largely carnivorous, feeding on a wide variety of organisms including
insects, crustaceans, and small fish (Baxter and Simon, 1970).
4.5.3 Impacts Resulting From Specific Alternatives
Segment 1 - Golden to Youngfield Street
Critical low flows in the year 2000 will remain extended from the
Croke Canal diversion to Youngfield Street in Segment 1 during the
winter. The year 2000 flows will increase slightly from the Golden/Coors
-------
4-29
WWTP effluent to Youngfield Street during the runoff through late irri-
gation seasons (April through October). This increase will provide
additional habitable space for fish and possibly allow the water's edge
to approach adjacent riparian vegetation throughout a greater portion
of the year. However the excessive stream channelization will remain a
major limiting factor in the perpetuation of a fishery throughout
Segment 1.
> Residual chlorine, BOD, phosphorous, and ammonia concentrations
within Clear Creek may increase during the fall due to the Golden/Coors
WWTP depending on the establishment of the various proposed water quality
standards. Since few fish have been collected in this section of Clear
Creek it is assumed that the establishment of either set of standards
will not have a dramatic affect on the fishery during the fall and
virtually no affect during the winter, when the Golden/Coors WWTP dis-
charge is rerouted to the Croke Canal. Therefore the major factors which
are presently limiting the fishery in this section, which include fluc-
tuating flows, the lack of in-stream and riparian habitat, will also be
limiting in the year 2000.
Segment 2 - Youngfield Street to Wheat Ridge WWTP
The increase in September flows, described in Table 4-3 of section
4.3, that will be realized throughout Segment 2 due to the project
will apply generally to the non-winter months and will provide additional
potential for the existing fishery. The increased flows will also
benefit Clear Creek by purging excessive nutrients accumulated throughout
the summer from pools and preventing possible eutrophication which would
result in organic decay and dissolved oxygen depletions. Critical low
flows will, however, remain throughout the segment during the winter. If
snow cover and an ice cap persists on the stream and nutrients accumu-
lated throughout the summer remain in the stream during the winter, low
flows may further stimulate eutrophication by not supplying aerated water
to the pools.
-------
4-30
Generally warm water species are capable of tolerating lower
dissolved oxygen concentrations, which may be experienced throughout
this segment during the winter. The Channel Catfish (Ictarurus
punctatus), which has been introduced to Segment 2 by the Colorado
Division of Wildlife, may be adversely affected by these future winter
conditions, as it is one of the first warm water species to be stressed
by lower dissolved oxygen concentrations. Future investigations should
be conducted to determine the actual reduction, if any. in concentrations
of dissolved oxygen during the winter, as present winter flows in Segment
2 are expected to approximate the projected future flows.
As noted in Section 4.4 the water quality of Clear Creek below
Kipling Street, during the periods of low flow, will approximate the
quality of water from non-point sources. The non-point source components
which would indirectly affect the fishery, if excessive loadings are
introduced, are phosphorous and nitrogen, which can stimulate the growth
of algae and other forms of aquatic life. This profuse growth would
result in an over abundance of these organisms which, through growth and
decomposition, would produce objectionable odors and deplete dissolved
oxygen supplies, especially during low flows.
During the fall, water quality in Segment 2 will probably depend on
the standards eventually adopted. The water quality standards proposed
by the Adolph Coors Company for ammonia and residual chlorine, if
equalled or exceeded instrearn, could become hazardous to the warm water
fishery of Segment 2. The Colorado Department of Health, in proposing
their standards, have taken into consideration warm water fisheries
preservation and if equalled should not be injurious to the fishery. The
Colorado Division of Wildlife has recommended general limitations for the
preservation of aquatic life which are more stringent than the standards
proposed by Coors and CDH. The CDW's reasoning behind the stringency is
based on the fact that many specific toxicants are generally in solution
together and will act additively in their mode of toxicity (Davies and
Goettl, 1976). The possible high concentrations of iron and copper
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4-31
should remain at their existing levels during the winter because the
present flows are similar to those projected for the 7ear 2000. During
the fall iron and copper concentrations may be reduced, based on the
projected increased flows provided by the Golden/Coors WWTP.
Segment 3 - Wheat Ridge WWTP to South Platte River
Provided existing WWTPs remain in operation, Segment 3 would realize
a slight increase in flow from the Wheat Ridge WWTP to the Clear Creek
and Platte River Ditch diversion, as discussed in Section 4.3, during the
late irrigation and runoff seasons. These flow inundations would
slightly increase the habitable space that is presently wanting due
to restricted flows. Positive effects would be more noticeable in the
upper part of this segment. In the case of WWTP abandonment, decreases
in flow would be realized from the Wheat Ridge WWTP to the Clear Creek
and Platte River diversion, further inhibiting the fishery through
increased areas of water stagnation which could result in decreased
concentrations of dissolved oxygen.
Coors has proposed ammonia concentrations which, if equalled or
exceeded, may be harmful to the existing fishery. The CDH proposed
standards for Segment 3 are equivalent to those proposed for Segment 2.
With the abandonment of the WWTPs, the concentrations of unionized
ammonia and residual chlorine are expected to sharply decrease resulting
in the enhancement of Segment 3 for fishery habitat. However, the large
reduction in flows, resulting from the abandonment of the WWTPs and the
proportional increase in non-point source contributions, discussed
earlier, will render Segment 3 of Clear Creek potentially uninhabitable
for most warm water fish.
/
4.6 AGRICULTURAL LANDS
4.6.1 Summary of Impacts
As noted in Section 4.2 and Table 4-1, effects of the proposed
project on irrigation ditch flows would be confined to the Slough
Association, the Fisher Ditch, the Clear Creek and Platte River Ditch,
and the Colorado Agricultural Ditch. This discussion focuses on the
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4-32
affected ditches, considering type of croplands served and land use
planning considerations relevant to ditch service areas.
Although flow and ditch diversion impact projections presented in
Sections 4.2 and 4.3 were done for May and September, the impacts in
August and October are likely to be similar to those described for
September, and impacts for June can be expected to resemble those
described for May. During September, under Conditions 2 and 4 (treatment
plants in operation), all affected ditches receive increased flows
relative to baseline flows. Under Conditions 3 and 5 (treatment plants
closed), the Slough Association ditches receive a 21-28 percent increased
flow. Negative flows accrue to the Fisher Ditch (43 percent in the year
2000 and 56 percent under present conditions), the Clear Creek and Flatte
River Ditch (43 percent reduction from current flows under both the
V
current and year 2000 conditions), and the Colorado Agricultural Ditch
(no projections made, but the magnitude of loss would probably be similar
to that of the Clear Creek and Flatte River Ditch).
During the May period, no impact or a positive flow effect is
projected under Conditions 2 and 4 for all affected ditches. Under
Conditions 3 and 5, however, the Colorado Agricultural and Clear Creek
and Platte River Ditches receive reduced flows. Thus, the most signifi-
cant flow reductions are expected to accrue to the Clear Creek and
Platte River Ditch and the Colorado Agricultural Ditch.
4.6.2 Slough Association
The Slough Association consists of 20 different ditches. Detailed
information on the ditches could not be obtained because many of the
ditch operators or share owners do not retain data on their ownership
(Rock, 1980). To determine a service area for the Slough Association, it
was assumed that all lands between Ralston Creek, Swadley Ditch, and
Clear Creek are served by the Association ditches.
The principal agricultural land uses in the Slough Association
service area are truck gardening, pasture, and hay cultivation on small
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4-33
parcels. It is unclear to what extent the owners of these agricultural
parcels would benefit from the projected increased flows accruing to the
Slough Association ditches due to implementation of the proposed project.
Within the Slough Association service area, which is located in the
City of Wheat Ridge, twenty-six agricultural parcels, totalling about 140
acres, were identified. There are, however, a large number of parcels
not inventoried due to their very small size. Only three of the inven-
toried parcels are located in areas planned for conservation or open
space in the City of Wheat Ridge Comprehensive Plan (no date). Most of
the remaining parcels are expected to undergo urbanization in the for-
seeable future, with the smaller parcels most likely to remain in
"pleasure farming" uses. Given the expectation that many parcels will
urbanize, the beneficial impacts of increased ditch flows, if any, would
be temporary.
4.6.3 Fisher Ditch
Fisher Ditch services lands in the eastern portion of the Clear
Creek Basin, and many of its shares are owned by United Water Company,
which services lands located to the east of the Clear Creek Basin
boundary (Figure 4-5). These two ditches service small parcels of land,
totalling approximately 68 acres, devoted primarily to truck gardening,
but much of the water is used for municipal and industrial purposes
(Firole, 1980).
The service areas of the Fisher and United Water Company Ditches
are located within unincorporated Adams County. While the Adams County
Land Use Plan (1975) designates this area for urban development, the
plan is not site-specific. However, development pressures in the area
are high, and since none of the agricultural parcels are located in a
floodplain (Figure 4-5), it can be expected that most would undergo
development in the forseeable future even in Che absence of Che proposed
interceptor project. Thus, the impact of reduction in ditch flows on
agriculture in the area (conditions 3 and 5) is assessed as slight. It
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IRRIGATION DITCH SERVICE AREAS
FLOOD PLAIN AREAS (SOURCE: DENVER REGIONAL
COUNCIL OF GOVERNMENTS)
I - CROPLAND UNSEGREGATED NURSERIES. FLOWERS,
TREES, PLANTS
4- VEGETABLE AND CROPLAND
6- IMPROVED HAY CROPLAND
(IRRIGATED OR FERTILIZED)
AFFECTED AGRICULTURAL LANDS
FISHER DITCH SERVICE AREA
DAMES &MOORE
FIGURE 4-5
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PAGE NOT
AVAILABLE
DIGITALLY
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4-35
is uncertain whether the increased flow impacts (conditions 2 and 4)
would result in increased agricultural productivity in the Fisher Ditch
service area because flows have historically been adequate for fanning
(Firole, 1980). However, the United Water Company ditch has recently
experienced dryness in August (Gaccetta, 1980) and increased flow into
Fisher Ditch may therefore increase agricultural productivity in the
United Water Company service area.
4.6.4 Clear Creek and Platte River Ditch (CCPRD)
About 40 percent of the water from the CCPRD is used by Northglenn,
Thornton, and Adams County, with the remainder used for irrigation of
truck gardens at the upper end of the ditch, and corn, wheat, hay,
small grains, and vegetables at the lower end (Fukaye, 1980). Total
agricultural acreage is about 3,046. The entire service area is located
east of the Clear Creek basin, as shown in Figure 2-10. Lands within the
CCPRD service area are very fertile (Perea, 1980); some are Prime
Agricultural Lands (Denver Regional Council of Governments, 1977b).
Most of the agricultural lands are located in floodplains or in
lands zoned for mineral conservation. Some of those lands not in flood-
plains are designated for urban development in the Adams County
Comprehensive Land Use Plan but are owned by families who have farmed
them for years and are unlikely to sell to developers (Perea, 1980).
Thus, it can be expected that a large proportion of the agricultural
lands serviced by the CCPRD would remain in production in the absence of
the proposed project.
Under Conditions 2 and 4, no decrease in CCPRD flows is expected
(see Section 4.2). The projected decrease in flows under Conditions 3
and 5, however, is substantial, and a commensurate decrease in agricul-
tural productivity for CCPRD lands can be expected. This adverse impact
would occur in both the spring and August-October periods. Given the
productivity of agricultural lands serviced by CCPRD and the magnitude
of the projected water loss arising due to project implementation,
adverse impacts are considered to be substantial.
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4-36
4.6.5 Colorado Agricultural Ditch
The service area of the Colorado Agricultural Ditch overlaps with
that of the CCPRD. Many of the lands within the CCPRD and Colorado
Agricultural Ditch service areas use both sources for irrigation (Figure
2-10). Therefore, the same impacts described above for the CCPRD can be
expected for the Colorado Agricultural Ditch service area.
4.7 POTABLE WATER SUPPLIES
In addition to the impacts on agricultural lands along lower
Clear Creek ditches, the project will impact potable water supplies
identified in Table 2-3 and Section 2-7. Northglenn and Thornton
water supply diversion in CCPRD, Colorado Agricultural and Fisher
Ditches will be augmented if the in-basin WWTP's remain open (Condi-
tions 2 and 4). However, if the in-basin plants close (Conditions 3
and 5), these potable supplies will be significantly depleted from
present levels of Clear Creek use. As noted in previous sections,
Thornton and Northglenn have already begun phasing out use of these
lower basin diversions, so that the loss of streamflow in the lower
reach may not affect them in the future. However, closure of the in-
basin plants will probably improve dry weather water quality in the
depleted lower basin ditch diversions, which would be a benefit to the
Thornton and Northglenn water systems.
The latter comment holds true for Crestview W&SD diversions through
Kershaw Ditch. Moreover, Crestview will not be injured by flow deple-
tions in Conditions 3 and 5, so the net impact will be beneficial to
Crestview. Crestview would be unaffected in Conditions 2 and 4. Other
municipal diversions for potable use are made above the reach of Clear
Creek affected by the project.
Impacts on individual potable supply wells or Coors process supply
wells in the basin will depend on the degree of contact and translation
of surface water quantity and quality into the alluvial aquifer. This
phenomenon varies from place to place depending on aquifer thickness
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4-37
and composition and the hydrological relationships between well loca-
tions and the creek. Impacts cannot be determined on the basis of
these studies.
A.8 RECREATION
Implementation of the proposed interceptor plan would create
opportunities for recreational uses of the right-of-way. The recrea-
tional opportunities afforded by the proposed project would consist of a
bikeway route, hiking trail, or horse trail, with a horse trail being
most likely. However, the presence of the existing Clear Creek bike
route could be an impediment to the chances for federal or state funding
for trail installation.
The proposed interceptor route generally follows, but does not
coincide with, the Clear Creek trail designated in the Denver Regional
Council of Governments' Regional Growth and Development Plan. It is
unclear whether or not the agencies that would be involved in the A-95
review process would support the concept of a parallel trail, nor is
there evidence that local jurisdictions would be willing to provide
funds, even on a federal matching basis, for such a trail.
MDSDD was created under Colorado's Metropolitan Districts Act of
1961, which enabled organization of sewer service agencies in multi-
jurisdictional areas. The potential for agencies created under the Act
to be involved in recreation planning was not addressed in the legisla-
tion, nor have legal opinions been formally rendered. MDSDD has been
involved in some recreational planning activity through contacts with
local government agencies, but the opinion of its legal staff and Board
of Directors is that while some involvement in cooperative recreation
facility planning with local governments is appropriate, significant
expenditures for recreational use of MDSDD facilities are not within the
scope of MDSDD's legal functions. While MDSDD may be willing to submit
grant applications for recreational investments (such as those covered by
Section 201 of the Clean Water Act), as well as supervise construction,
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4-38
the local matching share for any significant expenditures would have to
be provided by local jurisdictions. However, to date no jurisdiction in
the Clear Creek Basin has communicated an interest in funding a recrea-
tional trail along the proposed interceptor right-of-way to MDSDD (Van
Royen, 1980).
Comments obtained from local jurisdictions regarding recreational
use of the proposed interceptor right-of-way are included in Appendix A.
While no written comments were received from the City of Wheat Ridge,
Mr. Rich Bredt, Director of Parks and Recreation for the city, communi-
cated (1980) the city's desire that any damage to the city greenbelt and
Clear Creek trail caused by construction be repaired. Mr. Bredt also
stated that the potential for a horse trail should be examined, but
that such a trail would probably be feasible only for the area west of
Kipling Avenue due to road crossing constraints. Written comments from
other jurisdictions generally support the use of the interceptor right-
of-way for a trail.
The primary opportunity for recreational use of the proposed inter-
ceptor right-of-way appears to be for a horse trail, due to the existence
of a hiking trail and bikeways in the corridor. As noted earlier, such
a trail would be most feasible between Youngfield and Kipling, an area
within the jurisdiction of the City of Wheat Ridge. The implementation
process involved, were the city to be interested in a horse trail, would
require cooperation between MDSDD and the city, with MDSDD making appli-
cation for EPA Section 201 funding for design and construction funds
(except Eor topcoating, which is not an allowable expense under Section
201), and the City of Wheat Ridge performing most of the design work and
providing the local 25 percent matching share. Funding for topcoating
the trail could come from the city's general funds, Jefferson County Open
Space sales tax revenues, the State Parks and Outdoor Recreation Division
(if funds become available), or the Heritage Conservation Society.
Successful implementation of a horse trail would, however, hinge on
cooperation between MDSDD and the City of Wheat Ridge.
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5-1
5.0 MITIGATION MEASURES
5.1 OBJECTIVES
Section 4.0 has shown that the proposed project will have signifi-
cant impacts on water rights and agricultural lands associated with
ditch diversions along lower Clear Creek. Also, the project will have
mixed and as yet non-quantifiable impacts on water quality and aquatic
habitat; these impacts will vary depending on water quality standards
and discharge requirements and the determination of required minimum
flows for summer and winter conditions on Clear Creek. The overall
objectives of the mitigation measures implemented will be to balance
needs of the Clear Creek Basin for improved wastewater treatment
facilities provided by the project with maintenance and enhancement,
where feasible, of the complex set of human environmental factors in
existence in the basin. These objectives are summarized as follows:
a. Improvement of aquatic life and recreation potential on Clear
Creek by having sufficient minimum flows and water quality in
improvable reaches;
b. Meeting water supply needs of basin communities;
c. Meeting water rights requirements;
d. Providing necessary wastewater treatment; and
e. Protecting agricultural lands serviced by Clear Creek water
where it is reasonable to do so.
5.2 STRATEGIES
Mitigation measures indicated by the analyses, observations,
and studies reported herein relate a) directly to the effects of the
proposed Clear Creek Interceptor project on streamflow and b) more
generally to enhancement of the Clear Creek Basin environment, especially
recreation and water quality.
Mitigation of Streamflow Depletions
1. Augment In-Basin Treatment. Revise the MDSDD service area
to allow additional municipalities such as North Table Mountain, Pleasant
View, Applewood, Fruitdale, Northwest Lakewood, and Westridge Co have
their wastewaters treated at the planned Golden/Coors municipal WWTP
(existing process WWTP). This would essentially involve "re-inventing"
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5-2
the 40th and Youngfield satellite plant alternatives considered in
facilities planning. However, differences would be plant ownership and
operation (Coors), discharge point upstream at Mclntyre (or Croke Canal
in winter, based on existing Coors operating procedures), and raw waste-
water transportation requirements and costs (plant is 3.4 miles upstream
from 40th and Youngfield). Assuming the existing in-basin plants close
by 1985 and flows just prior to closure are the same as the existing
situation totaling 4.47 MGD, an additional flow to the Golden/Coors plant
of 1.97 MGD would be required to make up the loss of flow. This assumes
Golden/Coors flow in 1985 is 2.73 MGD (McNeill, 1980b). This make up
flow could be provided by routing North Table Mountain and Applewood
wastewaters to the Golden/Coors plant.
If it is assumed that the year 2000 deficit of 2.45 MGD (exist-
ing in-basin plants at year 2000 flows (Table 4-2) - 5.45 MGD-minus
Golden/Coors year 2000-3.0 MGD) must be made up, then wastewaters from
North Table Mountain and Pleasant View could be routed to Golden/Coors.
It is interesting to note that these "satellite" service areas closely
resemble that of Alternative No. 2 in the Clear Creek Facility Plan
(CH.M Hill, 1977) with the deletion of Pleasant View or Applewood,
both of which were included in Alternative No. 2. Indications are that
the Golden/Coors plant (existing) has sufficient capacity for these
increased flows.
2. Pump Back Effluent. Pump sewage effluent from the MDSDD
Central Plant to provide augmentation of headgate diversons for ditches
on lower Clear Creek up through the Fisher Ditch which are impacted by
the proposed MDSDD interceptor. Alternatively, effluent could be pumped
directly to the irrigated lands or major industrial or municipal users.
Cost, engineering, and health factors would dictate the most feasible
arrangement. Pumping distance from the MDSDD Central Plant to the Fisher
Ditch would be about five miles. Also, effluent could be pumped to a
point higher in the basin (say, Youngfield Street) to augment streamflow
in the most desirable segment for aquatic life (Youngfield to Wadsworth)
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5-3
as well as providing additional supplies for diversions at ditches on
lower Clear Creek. The effluent supplied would have to come from the
fraction of Central Plant flows originating as potable water supplies in
the South Platte River Basin, since the Blue River Decree limits Denver
Water Board use of Blue River trans-mountain water supplies to "municipal
purposes" (Bishop, 1980).
3. Revision of Standards. Closure of the existing in-basin
WWTP's could possibly be averted by changing the in-stream classification
of Clear Creek below the Wheat Ridge WWTP discharge to reflect no aquatic
life uses. This would allow the plants to function at essentially their
existing levels of treatment. Alternatively, the existing standards can
be tightened, as is now being considered by the Colorado Water Quality
Control Commission, to assure that discharges from remaining in-basin
plants such as Golden/Coors, do not degrade water quality. This will
nearly assure closure of the existing in-basin plants and increase the
influence of non-point pollution sources.
4. Purchase In-SCream Flow Rights. Colorado Water Law has been
revised to allow the purchase of water rights for maintenance of in-
stream uses such as aquatic habitat. A consortium of local governments
and the Colorado Division of Wildlife benefiting from habitat maintenance
could be formed to fund such a program. Such rights could be obtained
for the segment of Clear Creek above the lower end ditches, so that the
reserved water would become available for their diversions.
5. Transfer Points of Diversion. In recent years Thornton has
begun phasing out diversions for water supply at lower Clear Creek
ditches (Lower Clear Creek and Platte River, Colorado Agricultural, and
Fisher Ditches) because of poor water quality. Thornton plans to make
increasing use of Standley Lake and diversions higher in the basin
(Church, Farmers Highline, and Croke Canals) for future supplies.
In-stream flow maintenance, described above in item 4, could be further
enhanced if they maintained a portion of their water supply diversions at
the lower Clear Creek Ditches. More stringent standards, enforcement of
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5-4
permits and closure of existing in-basin WWTP's would help produce
adequate raw water quality.
Mitigation of Basin Water Quality Problems
1. Mine Drainage. Water quality in the Clear Creek Basin will be
enhanced by implementation of reclamation plans for the Argo Tunnel and
North Clear Creek now under study by the Colorado Mined Land Reclamation
Board. High Copper and Zinc concentrations in the most favorable aquatic
habitat segment from Youngfield to Wadsworth could be avoided. CDH and
EPA enforcement of permits and standards for mining operations could be
stepped up to avoid recurring problems. Also, enforcement authority over
inactive mines should be reviewed to see that the maximum effort possible
is expended within Colorado and Federal laws to control future pollution
problems associated with expected increases in mining activities.
2. Sanitary Landfills. New standards in place provide adequate
siting criteria for new landfills. Additional studies should be under-
taken to monitor and Inventory closed landfills and determine which are
causing pollution problems in Clear Creek. Landfills should be relocated
where feasible; or, controls such as leachate collection and treatment or
ground water regime modification should be implemented.
3. Urban Runoff Control. The increasing influence of non-point
sources, particularly urban runoff, must be checked to assure improved
Clear Creek Water quality. Studies underway and continuing by DRCOG with
the U.S. Geological Survey should be tied together for the Clear Creek
Basin in a master plan. Elements would possibly include a) institution-
alized "best management practices", b) design standards for new develop-
ment, including catchment basins for sediment control, c) control of
existing sub-basin discharges at critical points, and d) enforcement.
Centralized control and enforcement may have to be considered to provide
effective application of requirements.
4. Review Permit Basis. These studies have shown much lower
Clear Creek flows at the points of discharge for existing in-basin plants
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5-5
than the 7Q10 of 42.7 cfs apparently used by DRCOG in preparing the 1974
wasteload allocation used as the basis for NPDES permits issued in the
basin. Flow data developed herein should be reviewed and the low flow
for permit issuance reconsidered, so that real impacts of wastewater
discharges on Clear Creek can be reduced in the future.
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6-1
6.0 REFERENCES
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Zoning (with revisions), map.
Adams County Board of County Commissioners, 1979, Adams County water
report.
Adams County Planning Commission, 1975, Adams County Comprehensive
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cations, August.
Anderson, Dale, 1980, Water Commissioner, Water District 7, Colorado
Division of Water Resources, personal communication, August 7.
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economic effects on the local agricultural economy of water transfer
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Arvada, City of, 1979, City of Arvada Comprehensive Plan.
Barton, B. A., 1977, Short-term effects of highway construction on
the limnology of a small stream in southern Ontario. Freshwater
Biology. 7:99 - 108.
Barton J. R., D. A. White, P. V. Winger, and E. J. Peters, 1972, The
effects of highway construction on fish habitat in the Weber River,
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Baxter, G. T. and Simons, J.R., 1970, Wyoming fishes, Wyoming Game and
Fish Department, Cheyenne, Bulletin No. 4.
Beckman, William C., 1974, Guide to the fishes of Colorado, University of
Colorado Museum, Boulder.
Belding, D.L. 1972, Toxicity experiments with fish in reference to
trade waste pollution, Trans. American Fish Soc. 57:100-114.
Bell, Richard, 1980, Water Resources Geologist, Colorado Division of
Water Resources, personal communication, October 17.
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6-2
Bingham, D.A., 1968, The stream bottom as an indicator of pollution,
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Council of Governments, - Three Volumes, Project No. IGA-00034.
Black & Veatch and DRCOG, 1974, Wasteload allocation plan, DRCOG.
Bolander, Adolph, 1980, President, Farmers Reservoir and Irrigation
Company, personal communication, August 25.
Boyce, Keith, 1980, Assistant Manager, Crestview Water and Sanitation
District, personal communication, August 21.
Bredt, Rich, 1980, Director of Parks and Recreation, City of Wheat
Ridge, personal communication, September 16 and October 14.
Bishop, Gary E., 1980, Denver Water Department, Letter with information
on water supply and use in the Denver water system, August 21.
Brungs, W. A., 1969, Chronic toxicity to Fathead Minnows, Pimephales
promelas Rafinesque. Trans. Amer. Fish. Soc. 98:272.
Brungs, W. A., E. N. Lenard, and J. McKim, 1973, Acute and long-term
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Brungs, W.A., 1973, Effects of residual chlorine on aquatic life,
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on chemical toxicity to aquatic organisms, Journal of the Water
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Division 1, State of Colorado, August 27.
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judgment and decree in the matter of the application for change of
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in Water Division 1, July 18.
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6-3
Case No. W-7690-74, 1975, Findings of fact, conclusions of law and
decree approving a plan of augmentation and adjudicating an
appropriate right of substitution and exchange in the matter of the
application for water rights of Adolph Coors Company, District Court
in Water Division 1, filed February 25.
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and exchange in the matter of the application for water rights of
the City of Arvada in Water Division 1.
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in the matter of the application for water rights of the City of
Northglenn in the South Platte River and its tributaries.
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tributaries.
Case No. W-8762-77, 1977, Application for approval of plan for augmen-
tation including exchange and change of water rights in the matter
of the application for water rights of the City of Arvada on the
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tation, including exchange, and changes of water rights in the
matter of the water rights of the City of Thornton in the South
Platte River and its tributary Clear Creek in Adams County,
Colorado, December 31.
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politan Denver Sewage Disposal District No. 1, D9728.80.
CH2M Hill, Inc., 1975, Model pollutant loading rates for land surface
washoff functions, DRCPG Task memorandum #5-2 D09523E0.20.
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areas, MDSDD, Denver, Colorado.
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City and County of Denver, undated, Storm drainage master plan maps,
Department of Public Works.
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6-4
Colorado Division of Water Resources, 1980, Master well list by location,
CDWR, Denver.
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Selected ditches in Water District 7, Denver.
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Selected ditches in Water District 7, Denver.
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trails system, progress report 1974, Parks and Outdoor Recreation
Division.
Colorado Division of Water Resources, 1965, Daily diversion records,
selected ditches in water district 7, Denver.
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quality standards, proposed Water Quality Division, Denver,
Colorado.
Colorado State Highway Department, no date, Project I-76-(35) 1-70 to
1-25.
Colorado Water Quality Control Commission, 1980, Deposition of Phillip
Goebel, et al., Stream Classification hearings, July 2.
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Golden/Coors representatives, Stream Classification hearings, July
18.
Commerce City, City of, 1978, Commerce City zoning map.
Commerce City, City of, 1976, Commerce City Recreation and open space
plan, Department of Community Development.
Commerce City, City of, 1975, Commerce City land use plan, 1975-2000,
Department of Community Development.
Consolidated Cases Nos. W-8036(75) and W-8256(76), 1977, Findings
of fact, conclusions of law and decree approving: (1) a plan of
augmentation including exchange, (2) changes of water rights and
adjudicating: (1) groundwater rights and (2) appropriative rights
of substitution and exchange under the provisions of 1973 C.R.S.
37-80-120 for water rights of Adolph Coors Company, District Court
in Water Division 1, filed April 15.
Daber, Jim, 1980, Colorado Water Conservation Board, personal communi-
cation, October 17.
Daughtery, Pat, 1980, City of Arvada, personal communication,
September 9.
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6-5
Davies, P.H. and J.P. Goettl, Jr., 1976, Aquacic life - water quality
recommendation for heavy metals and other inorganic toxicants in
freshwater, Report for Water Quality Standards Revision Committee
and Colorado Water Quality Control Commission.
DeBelle, Vincent, 1980, Superintendent, Boyles Ditch Company, personal
communication, August 18.
Deeds, Bob, 1980, Jefferson County, Engineering Department, personal
communication, September 9.
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opment plan for the Denver region.
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in the Denver area, DRCOG, Task Memorandum #520.1.2.3, D9523.KO.
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water program, Denver.
Denver Regional Council of Governments, 1974, FY74 Segment Plan for Clear
Creek, DRCOG, Denver.
Denver Regional Council of Governments, no date, floodplain maps.
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resources 1975-2910, Denver Water Department, Three Volumes.
^
Dexter, Robert, 1980, Superintendent, Consolidated Reno and Juchem
Ditch Company, personal communication, August 18.
Dirrira, Lyle, 1980, Attorney for Farmers Highline Canal and Reservoir
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Dorrance, Bill and Doug Ryan, 1979, Methane site investigations,
Jefferson County Health Department, report in progress.
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the toxicity of industrial wastes and their components to fish II:
The metals as salts. Sew. and Ind. Wastes, 25:802.
Ellis, N. M., 1914, Fishes of Colorado, University of Colorado, Boulder,
University of Colorado Studies, Vol. II, #1.
-------
6-6
Engineering Consultants, Inc., and Toups Corporation, (no date), Compre-
hensive water quality management plan, South Platte River Basin,
Colorado Department of Health, Water Quality Control Division.
Environmental Protection Agency, 1980, Final eavironmental impact
statement, Northglenn water .management program, EPA, Denver,
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Environmental Protection Agency, 1978, Denver regional environmental
impact statement for wastewater facilities and the clean water
program, EPA Region VIII, Denver, Two volumes, EPA-908/5-77-001A.B.
Firole, Larry, 1980, Ditch Superintendent, Fisher Ditch Company,
personal communication, August 16.
Fox, F. M. and Associates, Inc., 1974, Evaluation of sanitary landfill
demonstration project, 64th and Pecos Street, Adams County,
Colorado, Property Improvements, Inc.
Fukaye, Jim, 1980, Secretary of the Lower Clear Creek and Platte River
Ditch Company, personal communication, August 28.
Gaccetta, Jim, 1980, Superintendent, United Water Company, personal
communication, August 21.
General Services Administration, 1979, Environmental impact statement for
the proposed master plan for the Denver Federal Center, GSA,
Denver, ECO-78001.
Gives, Guy, Bill Blackburn, and Dames & Moore, 1980, Jefferson County
Planning Department, numerous personal communications, September.
Goettl, John P. Jr., 1980, Evaluation of sport fisheries potential
in fluctuating plains streams. Job Progress Report, Federal Aid
Project F-77-R-1, March 1980.
Goudge, Charles L., 1980, City Manager, City of Golden, Colorado,
letter to William E. Korbitz, Manager, MDSDD, January 8.
Greenwood, Jim, 1980, Secretary, Lee, Stewart and Eskins Ditch Company,
personal communication, August 18.
Griggs, Joe, 1980, Superintendent, Rocky Mountain Ditch Company,
personal communication, August 18.
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substances known to be present in wastewater discharged into river,
Ann. Appl. Biol. 33:103-112.
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6-7
Grothe, D.R. and J.W. Eaton, 1975, Chlorine-induced mortality in fish,
Iran. Amer. Fish. Soc. 104: 800-802.
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Hendricks, David W. and Bluesteln, Mark H., 1976, Response of the South
Platte to effluent limitations, Journal of the Environmental Engi-
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Holm, Dave, 1980, Colorado Mined Land Reclamation Board, personal
communication, August 25.
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Colorado Department of Health, several personal communication,
September.
Jaquet, Neil G., 1980, Water Resources Engineer, Adolph Coors Company,
numerous personal communications, August and September.
Jefferson County Open Space, no date, Non-motorized recreation trails
plan.
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open space study/master plan.
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policy plan - phase one summary (pre-edited draft).
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the summer of 1889, with an account of the fishes found in each
river basin examined, Bull U.S. Fish Comm., IX 1889:1-40.
Keith, K. Lynn, 1980, Jefferson County Open Space, personal communi-
cation, September 16.
Klein, W. D., and Seaman, W. R., 1949, Clear Creek winter survival
experiment, memos, April 21.
Kloos, Jeannette, 1980, Federal Highways Administration, Washington,
D.C., personal communication, September 18.
Leffel, Ernest R., 1976, Direct environmental factors at municipal
wastewater treatment works, EPA Office of Water Program Operations,
Washington, D.C., MCD-20, EPA-430/9-76-003.
Leonard Rice Consulting Water Engineers, Inc., 1978, Water rights impacts
of Clear Creek facility planning, MDSDD, Denver.
Loving, Andy, 1980, City of Westminster Planning Department, personal
communication, August 1.
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6-8
McNeill, Ray, 1980a, Metropolitan Denver Sewage Disposal District
No. 1 (MDSDD), personal communication, August 14.
McNeill, Ray, 1980b, Projected district member annual flow and loading
data, 1980-2005, MDSDD, May 14.
McNeill, Ray, 1980c, Historical district member annual flow and loading
data, 1967-1979, MDSDD, March 25.
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report, sewer interceptors and sewage treatment for the metropolitan
area.
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personal communication, August and September.
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drainage on water quality in selected areas of Colorado, 1972-73,
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(Pimepholes promelas rafinesque). Water Res. 2:215.
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Fathead Minnow (Pimephales promelas) in soft water. Journal of the
Fisheries Research Board of Canada. 26:2449-2457.
Mungan, Paul, 1980, Colorado Parks and Outdoor Recreation Division,
personal communication, September 17.
MSM Consultants, Inc., 1979, Master drainage plan, City of Wheat Ridge.
Neill, Dwight, 1980, Secretary, Agricultural Ditch and Reservoir Company,
personal communication, September.
Ospina, F. E., 1980, Department of Community Development, City of
Lakewood, personal communication, September 9.
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cation, August 20.
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heavy metals to different species of warm water fishes. Air/Water
Poll. 10:453-463.
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on the growth of channel catfish (Ictalucus punctatus), The
Progressive Fish Culturist, 38: 26-29.
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6-9
Rock, Bob, 1980, Slough Association, personal communication, August 25.
Rullo, Louis, 1980, Secretary of the Colorado Agricultural Ditch
Company, personal communication, August 28.
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9.
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to Don Allard, MDSDD, with enclosure-EPA evaluation of the impacts
on Clear Creek water flow and water rights based on the Leonard Rice
study 3/80, June 30.
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and Hazardous Wastes Control Division, personal communication.-
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6-10
Warnick, S.L., and H. L. Bell, 1969, The acute toxicity of some heavy
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streams in Colorado, 1971-72, Colorado Water Conservation Board,
Colorado Water Res. Cir. No. 21.
West, Donald, 1980, Colorado Parks and Outdoor Recreation Division,
personal communication, September 17.
Westminster, City of, 1980, official zoning map, sheet 2 of 2.
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Water facilities for city of Golden, Golden, Colorado.
Wilson, Wes, 1980, Environmental Protection Agency, Denver, personal
communication, September 16.
Williams, John, 1980, Attorney for Wheatridge Sanitation District,
personal communications, August and September.
Woodling, John, 1980, Fisheries Biologist, Colorado Division of
Wildlife, personal communication, October 14.
Woodling, John, in preparation, Water quality studies of Clear Creek.
Wright-McLaughlin Engineers, 1979, Water reclamation study, City of
Arvada.
Ziegler, Jim, 1980, Laketender, Croke Canal, personal communication,
August 18.
Zillich, J.A., 1972, Toxicity of combined chlorine residuals to fresh-
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44: 212-220.
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APPENDIX A
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city ofarvada
RALSTON ROAD
ARVADA. COLORADO 60002
PHONE 3O3-a21-25=O
September 9, 1380
Mr. David Clark
Mr. Paul Pigeon
Dames & Moore
1626 Cole Blvd.
Golden, Colorado 80401
Dear Mr. Clark and Mr. Pigeon:
We are in receipt of the plans for the Clear Creek Interceptor.
We find the plans for this interceptor in compliance with our
Comprehensive Plan, and would hope that the developmenmt of the
facility will be forthcoming in the very near future.
Ld L. Cfttnney
Director of Plann
DLK/jb
cc: Craig Kocian, City Manager
Don Ailard, Deputy City Manager
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10701 MELODY DRIVE. • SUITE 618 • NORTHGLENN. COLORADO 80234 . (303) 451-8326
September 10, 1980
Dames & Moore
ATTN: David C. Clark and Paul E. Pigeon
1626 Cole Boulevard
Golden, CO 30401
Dear Sirs:
Thank you for the opportunity to respond to the proposed Clear Creek
Interceptor Plans. We have reviewed the material which you sent us
along with your letter dated September 5, 1980, and have no negative
comments. He are very supportive of the regional trail system concept
and would hope that any damage done to existing segments of the trail
during the time of construction will be promptly and properly replaced.
Also, we would encourage the inclusion within the plans for this
project provisions for extension of the trail by me.ans of appropriate
land shaping and regrading of the corridor to accommodate a future
trail.
of CommunTty Development
JDS/jk
EPAHTMENT OF COMMUNITY DEVELOPMENT
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BOARD
OF
COUNTY COMMISSIONERS
COMMISSIONERS
Bob Bnggs
Ed Harshbarger, Jr.
W.H. Sim Eppinger
ADMINISTRATION BUILDING
450 SOUTH 4TH AVENUE
BRIGHTON, COLORADO 80601 ADMINISTRATIVE DIVISION
303-659-2120 PLANNING AND ZONING
September 10, 1980
Mr. David Clark
Mr. Paul Pigeon
Dames § Moore
1626 Cole Blvd.
Golden, Colorado 80401
Dear Mssrs. Clark and Pigeon:
Thank you for your letter dated 5 September 1980 requesting
suggestions for alternative multiple uses of the proposed Clear
Creek Interceptor right-of-way. It is my understanding that
Jon Colt of the Adams County Planning Department Staff has con-
tacted Mr. Pigeon and conveyed to him concerns about the flow
changes and loss of agricultural land/productivity which would
be brought about as a result of the construction of the inter-
ceptor. He also informed me that he loaned copies of the 1979
Water Report and relevant correspondence on the flow issue to
your staff for review. I would appreciate the return of those
documents to us after your use.
Relative to the question of alternative multiple uses of
the interceptor right-of-way, please be advised that Staff feelings
persist regarding trail system use for the proposed development
area.
Once again, thank you for the opportunity to respond to
your comment.
L. Considine
Acting Planning Director
JLC:ljo
cc: Jon Colt
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CITY AND COUNTY OF DENVER
DENVER PLANNING OFFICE
~~^^m^^^-
w. H. MCNICHOLS. JB. DENVER, COLORADO 80202
ROOM 400 ^
1445 CLEVELAND PLACE
DENVER, COLORADO J
PHONE (303) 575-2736
September 15, 1980
Dames and Moore
1626 Cole Boulevard
Golden, Colorado 80401
Attn: Mr. David C. Clark
Mr. Paul E. Pigeon
Dear Sirs:
Referring to your letter of September 5, 1980, the Denver Planning
Office is pleased to offer the following comments regarding the
proposed Clear Creek Interceptor sewer. We assume you are talking
about alternative 1, although your letter does not specify.
1) The Planning Office is not ready to concede that a "Finding
of No Significant Environmental Impact" is appropriate in
the case of the proposed Clear Creek Interceptor. This
issue should be decided in a public forum.
The Clear Creek facility plan devoted ten full pages to
environmental impacts including proposed mitigation meas-
ures. We generally find no problem with the findings of the
consultant (O^M Hill) and would affirm our support for the
environmental mitigation measures proposed in the August
1977 study.
2) Tour letter asks for comments on potential multiple uses of
the proposed interceptor right-of-way without presenting
alternatives for us to comment upon. We therefore have no
comment to offer at this time.
3) We suspect, although it is difficult to determine fron the
vagueness of your correspondence, that any letter from us
may be construed as an approval of EPA's "Finding of No
Significant Impact" in the case of the proposed Clear Creek
Interceptor Sewer.
Nothing could be further from the truth. In addition to the
ten pages of environmental impacts described in the facility
plan there are other significant environmental issues invol-
ving the question of water quality and water rights on Clear
Creek. It is difficult for us to believe that the specific
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Clark & Pigeon September 15, 1980 page 2
environmental issues along this long corridor can be reduced
to a brief "Finding of No Significant Impact."
4) The Planning Office is of the opinion that Clear Creek should
not be subjected to the same set of unreasonable additional
conditions that were imposed on Sand Creek by the EPA. We
take note of the fact that the Clear Creek and Sand Creek
study consultant did not recommend such mitigation measures
as sewer tap limitations, air quality stipulations, flood
plain ordinances, street sweeping ordinances and other
dictatorial, peripheral measures.
The central issue is not so called "growth"control, it is the prompt
provision of needed sanitary sewer services to protect the health,
safety and welfare of the metropolitan community. Until this issue
becomes a top priority at all levels there will be no reasonable
progress made in the protection of the human environment in this
region.
Finally, the very narrow approach in your letter and the provision
of extremely limited information on this major sewer issue is
somewhat disturbing. Perhaps if the right questions were being
asked it would save all of the responsible parties a great deal of
time.
,y lours
L. Canter
Director of Planning
cc: H. Cook
J. Zohn
ALC/WW/mb
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fflk COMMERCE CITY
. i cotorudo
NOUSIRy
Department of
Community Development September 24, 1980
Dames and Moore
Attn: • David C. Clark
1626 Cole Blvd.
Golden, CO 80401
Dear Mr. Clark:
Thank you for the opportunity to review the proposed Clear Creek Interceptor
project. /
Our planning staff recently submitted the project to Commerce City's Growth
and Development Committee and the Planning Commission for their consideration.
Upon completion of the review it has been decided that the project will not
adversely impact the relatively small portion of the Commerce City area for
which it is proposed.
The concerns expressed during the review centered around the general location
of the interceptor route in relation to existing.and proposed portions of the
regional recreation system of the Denver Metro area.' In this regard we would
suggest that, wherever feasible, the inceptors route facilitate pedestrian
access, either directly or indirectly, to this system.
Commerce City has been discussing with Adams County the possibility of
developing a portion of this trail system along an existing access road
located between the Burlington Ditch and South Flatte River. This portion
would extend from approximately 58th Ave. to 65th Ave. within our boundaries.
Since the inceptors route enters Commerce City at the juction of the South
Platte River and 64th Ave., a potential exists for establishing pedestrian
access to this portion of the system.
We would appreciate your consideration of this concept. If you have any
additional questions please contact me at 287-0151 extension 232.
Sincerely,
Gene Kovacs,
Planner II
GK/dj
6015 forest drive/p.o. box 40/commerce city. Colorado 80037 (303) 287-0131
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before comulenng)
1. REPORT NO.
EPA 908/5-81-002
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Technical Report Appendix to Finding of No Significant
Impact, Clear Creek Interceptor Project
5. REPORT DATE
January 1981
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S)
Michael A. Gansecki, EPA, Project Officer
Paul Pigeon, Dames and Moore, Project Manager
8. PERFORMING ORGANIZATION REPORT NO.
9 PERFORMING ORGANIZATION NAME AND ADDRESS
Dames and Moore
1626 Cole Boulevard
Golden, Colorado 80401
10. PROGRAM ELEMENT NO
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Region VIII
1860 Lincoln Street
Denver, Colorado 80295
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
8W-EE
15. SUPPLEMENTARY NOTES
Accompanies a Finding of No Significant Impact, Clear Creek Interceptor Project,
Metro District, Commerce City, Colorado
16 ABSTRACT
The report evaluates the segment of Clear Creek from Golden, Colorado to its
confluence with, the South Platte River. It was determined that additional study
was necessary to define the water flow changes, water quality, aquatic life and
water rights changes that would occur with the implementation of the Metro District's
Clear Creek Interceptor. The study also considered the added effect of the newly
proposed Golden/Coors wastewater treatment plant.
The study effort developed a flow balance on Clear Creek taking into account
all diversions, return flows, etc. This balance was then used to predict effects on
water quality and aquatic habitat. A literature search and field investigation was
also done to define the aquatic habitat suitability of various Clear Creek stream
reaches. The study dSined impacts on existing irrigated agriculture from future
urban development.
A number of mitigation strategies were defined to try to protect the water
quality, aquatic habitat, and agricultural lands supported by Clear Creek. The
recommendations are considered in the Clear Creek Finding of No Significant Impact
document.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI held/Group
Sewer Interceptor
Aquatic Habitat
Streamflow Analysis
Agricultural Lands
Irrigated Agriculture Land Conversions
Metro District
Clear Creek
metropolitan Denver
13 DISTRIBUTION STATEMENT
Release Unlimited
19 SECURITY CLASS (This Report)
21 NO. O? PAGES
20 SECURITY CLASS /This page)
22 PRICE
EPA Farm 2220-1 (R«v 4-77) PREVIOUS ESI TIOS is ossos-s TE
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