United States
Environmental Protection
Agency
Total Maximum Daily Loads
TMDL at a Glance
Deer Creek Reservoir Total
Phosphorus
(approved September 2002)
www.waterquality.utah.gov/TMDL/Deer_Creek_Reservoir_
JMDLpdf
Factors causing impairment
Coldwater aquatic life use impaired by low dissolved
oxygen levels at the bottom of the reservoir caused
by excessive phosphorus loads and high surface water
temperatures that affect the reservoir's fisheries
Sources contributing to impairment
Nonpoint source runoff from urban areas and
agricultural activities; a fish hatchery
Restoration options
Implement agricultural best management practices,
cleanup potential concentrated animal feeding
operations, streambank restoration, load reduction
from fish hatchery, and develop comprehensive
nutrient management plans for feedlots casing water
quality impairments
Stakeholder involvement
Wasatch, Salt Lake, and Utah counties, Midway
Fish Hatchery, Jordanelle Reservoir Water Quality
Technical Advisory Committee, five regional
conservancy districts, Utah Department of
Environmental Quality
Status of waternody
Met annual phosphorus load reductions established
by the TMDL to allow for future growth and a margin
of safety during 2006 and 2007; mixed success in
meeting other endpoints established by the TMDL to
maintain good water quality
Using the TMDL Process to Maintain and Protect
Water Quality
In 1941, the Bureau of Reclamation completed construction of the Deer Creek Reservoir,
located on the Provo River in Wasatch County, Utah. Since that time, Deer Creek
Reservoir has become a vital source of drinking water for over one million people,
as well as a source of irrigation water and a popular recreation destination. In
the 1980s, concerns over excessive nutrients in Deer Creek Reservoir led to
the formation of the Jordanelle Reservoir Water Quality Technical Advisory
Committee (JTAC), the group responsible for the development of a water quality
management plan for Deer Creek and Jordanelle reservoirs. Although Deer Creek
Reservoir at one time did not support the coldwater fishery beneficial use due to
low dissolved oxygen (DO) levels and high temperatures, analysis of recent data
from Deer Creek Reservoir through the TMDL process revealed that stakeholder
efforts led to significant improvements in both water quality and the health of the
reservoir's fishery. Despite these improvements, the TMDL analysis revealed that
DO levels remained a concern under certain conditions. Too much phosphorus
beyond the current loads could lead to algal blooms that would affect the quality
of the drinking water supply and require costly treatment. As a result, the TMDL
for Deer Creek Reservoir established quantifiable targets to maintain current
water quality and identified phosphorus reductions to provide a margin of safety
and allow for future growth in the watershed.
How are TMDLs at work in the Deer Creek Reservoir?
The TMDL process provided stakeholders with a framework for compiling,
analyzing, and understanding data for parameters affecting DO levels in the
Deer Creek Reservoir. The data analysis of factors contributing to the coldwater
fishery beneficial use impairment identified for Deer Creek Reservoir, including
dissolved oxygen levels, temperature, algae levels, water clarity, and fishery health,
all showed signs of improvement at the time of TMDL development. These
improvements are attributed to years of water quality improvement projects and
programs. Although the TMDL development process did reveal improvements
in water quality, it also highlighted the sensitivities of Deer Creek Reservoir. The
final TMDL report states that although major improvements are not needed, it
is important to have a plan in place that stresses protection and management of
current conditions—particularly in light of growth and development pressures
in Wasatch County. As a result, stakeholders were able to participate in the
development of a TMDL that establishes quantifiable goals to maintain current
Benefits to stakeholders
Clean water, recreation, aesthetics, economy, funding,
partnerships and education
What is a total maximum daily load (TMDL)?
It is a study or analysis that calculates the maximum amount of a pollutant that a waterbody can receive and still meet
water quality standards. The TMDL establishes a pollutant budget and then allocates portions of the overall budget to
the pollutant's sources. For more information on TMDLs, visit EPA's website at www.epa.gov/owow/tmdl.
-------
Deer Creek-2
phosphorus loads and identifies phosphorus reductions necessary to maintain a margin of
safety and allow for future growth.
Who were the participating stakeholders and key partners?
Development of TMDLs in the state of Utah is the responsibility of the Utah Department
of Environmental Quality (UDEQ). To develop total phosphorus TMDL for Deer Creek
Reservoir, UDEQ worked with key stakeholders and partners at the federal, state, and local
levels. The JTAC and the Central Utah Water Conservancy District (CUWCD) provided
data and technical tools used in developing the TMDL. Unlike TMDL development,
TMDL implementation is largely in the hands of other stakeholders and partners,
depending on the actions recommended by the TMDL. In the case of Deer Creek
Reservoir, there are nine key projects and programs identified in the TMDL necessary
to maintain current phosphorus loads, as well as provide additional load reductions.
These projects are the responsibility of local, state, and federal partners, including
Wasatch County, JTAC, CUWCD, the Utah Association of Conservation Districts, the
Utah Mitigation Reclamation and Conservation Commission, UDEQ, and the Natural
Resources Conservation Service.
How did stakeholders participate in the TMDL development process?
The overall TMDL process includes the following elements: Clean Water Act (CWA)
section 303(d) listing decisions, TMDL development, and TMDL implementation. Each
element of the TMDL process provided stakeholders with an opportunity to express
concerns and share information about the water quality problems in Deer Creek Reservoir
with UDEQ and other key partners. A description of each element of the TMDL process is
provided below.
Section 303(d) Listing Decisions
If a waterbody does not meet water quality standards (i.e., numeric or narrative criteria)
for one or more pollutants, it goes on a state's CWA section 303(d) list. Impaired
waterbodies on this list require a TMDL for each pollutant contributing to the
impairment. Stakeholders have the opportunity to provide input during the 303(d) listing
process. UDEQ placed Deer Creek Reservoir on Utah's 303(d) list in 2000 due to low
dissolved oxygen levels at the bottom of the reservoir and high surface water temperatures
—factors that affect the reservoir's cold water fisheries. UDEQ made the state's 2000
CWA section 303(d) list available to the public for review via the UDEQ Division of Water
Quality web site and published two public notices in two newspapers.
TMDL Development
To initiate the development of the Deer Creek TMDL, UDEQ analyzed existing data to
verifythe dissolved oxygen and temperature impairments. As a result of this analysis, the
final TMDL report recommended that UDEQ consider removing Deer Creek Reservoir
from the state's 303(d) list as having a temperature impairment. Removal from the CWA
section 303(d) list of impaired waterbodies is referred to as delisting.
Although the analysis revealed that Deer Creek Reservoir and its fishery are both healthy,
the data also indicated that the water quality is very sensitive. Changes in the current
phosphorus loads could affect the quality of the drinking water supply and result in
the need for costly treatment to control odor and improve taste. As a result, the TMDL
report emphasized the need to maintain phosphorus loads at current levels. The TMDL
development process included identifying quantifiable goals, also referred to as endpoints
or targets, established to maintain current phosphorus loads. The TMDL report identifies
seven endpoints that would serve as a yardstick to measure progress toward maintaining
current water quality conditions. The seven endpoints are as follows:
O Percent of the water column with dissolved oxygen concentrations below the target
threshold value to support beneficial use
-------
O No fish kills
O In-lake phosphorus concentration
O In-stream phosphorus concentration
O Annual and monthly (August-October) phosphorus loads to lake
O Average Trophic State Index (i.e., a measure of the relationship among nutrients, algal
biomass, and lake clarity)
O Algae biomass
To provide a margin of safety and to account for future sources, the TMDL analysis
identified point and nonpoint sources of phosphorus to the Deer Creek Reservoir and
assigned phosphorus load reductions to those sources. The TMDL analysis assigns
the Midway Fish Hatchery a wasteload allocation of 400 kilograms per year (kg/yr), a
160 kg/yr decrease in its current phosphorus load of 560 kg/yr. The TMDL reserved a
phosphorus wasteload allocation of 500 kg/yr for future point sources. Urban nonpoint
sources received a load allocation of 1,300 kg/yr, requiring a 300 kg/yr load reduction
from the current load of 1,600 kg/yr. The TMDL assigned a load allocation of 3,595 kg/yr
to agricultural nonpoint sources, a reduction of 2,465 kg/yr from the current phosphorus
load of 6,060 kg/yr. The TMDL analysis included a 900 kg/yr load allocation for future
nonpoint sources to allow for future growth. The TMDL also included a ten percent
margin of safety.
Throughout the TMDL development process, UDEQ worked with members of the JTAC
to obtain stakeholder input. In addition, UDEQ made the draft TMDL available for public
review and comment using both local newspapers and the Internet. UDEQ did not receive
comments from the public, but the final TMDL reflects input from the JTAC.
TMDL Implementation
The final TMDL report identifies nine restoration projects that, at the time of the final
TMDL, were either in process or recently completed. The nine projects identified as key to
TMDL implementation are as follows:
O Provo River Restoration Project
O Conversion to Sprinkler Irrigation Systems
O Heber Valley Water Quality Basins
O Cleanup of Potential CAFOs
O Integrated Watershed Information System
O Main Creek Stream Bank Restoration
O Agricultural BMP Projects
O Midway Fish Hatchery Settling Pond Installation and Maintenance
O Cautious Responsible Growth in Heber Valley and Jordanelle Basin.
The TMDL report estimates that these projects, implemented by local, state, and federal
partners, will generate approximately 2,965 kg/yr in phosphorus reductions at a cost of
approximately $38,100,000. Two of the nine projects—the Provo River Restoration Project
and the Conversion to Sprinkler Irrigation Systems—are associated with the Central Utah
Project Completion Act; as a result, phosphorus reductions associated with these projects
are secondary goals.
Deer Creek-3
-------
What is the current status of Deer Creek Reservoir as a result of the
TMDL process?
The 2008 Water Quality Implementation Report for the Provo River, Jordanelle Reservoir,
and the Deer Creek Reservoir, prepared for the Provo Watershed Council, provide a
summary of the data collected during the 2006 and 2007 water years. Table 1 provides
a summary of an assessment of progress in Deer Creek Reservoir during 2006 and 2007
using the endpoints established through the TMDL development process as a yardstick.
According to the 2006 and 2007 data, annual phosphorus loads to Deer Creek Reservoir
were below the 15,300 kg/yr total load allocation (i.e., current and future allocations to point
sources and nonpoint sources) established in the TMDL. However, monthly phosphorus
loads during the critical period of August-October exceeded the target loads set by the
TMDL during 2006 and 2007. The data show that Deer Creek Reservoir met the endpoints
for no fish kills and in-lake phosphorus concentration, but did not meet the endpoints for
DO concentrations in the water column, trophic state index, and algae biomass.
Table 1. Summary of Deer Creek Reservoir Endpoint Assessment for 2006 and 2007
Parameter (Proposed Target)
Percent of the water column with dissolved oxygen
concentrations below the target threshold value to support
beneficial use (<50% of column with DO <4.0 mg/l)
Fish habitat (No fish kills)
In-lake phosphorus concentration
(0.025 mg/l TP (Avg all depths))
In-stream phosphorus concentration
(0.030 mg/l TP and 0.020 mg/l DTP)
Total Phosphorus loads to lake: Annual
(15,300 kg/yr TP and 9,700 kg/yr DTP)
Total Phosphorus loads to lake: August-October
(560 kg/mo TP and 350 kg/mo DTP)
Average Trophic State Index (40-45)
Algae biomass (5.1 ug/l Chlorophyll a; 6.5 x 107um3/ml
Biomass; 3.3x 107um3/ml Cyanophyta)
Meet Endpoint in 2006?
No
Yes
Yes
Meet Endpoint in 2007?
No
Yes
Yes
[Information on this endpoint not provided
in the 2008 report]
Yes
No
No
No
Yes
No
No
No
How did local stakeholders benefit from the TMDL process?
Through the TMDL process, stakeholders had the opportunity to claim credit for water
quality improvements in Deer Creek Reservoir and play a role in establishing the future
direction of water quality management for the reservoir. Striving to achieve the water
quality management goals established in the TMDL will benefit stakeholders in a number
of ways.
O Allowing future growth without sacrificing water quality. By incorporating
pollutant load reductions and a margin of safety, the TMDL takes into consideration
the growth of Wasatch County without compromising the quality of the drinking
water and irrigation supply.
O Ensuring a high quality drinking water supply while keeping down treatment
costs. Deer Creek Reservoir is a major source of drinking water for over one million
people, distributed by five separate utilities located in Salt Lake, Utah, Wasatch,
and Summit counties. Although Deer Creek Reservoir supported its drinking water
designated use at the time of TMDL development, the TMDL process revealed the
sensitive nature of the reservoir and helped stakeholders set goals to prevent future
drinking water designated use impairment.
Deer Creek-4
-------
O Improved recreational opportunities and aesthetics. Maintaining and reducing
phosphorus loads will help to keep Deer Creek Reservoir free from nuisance algae
blooms that can affect recreational enthusiasts desire to enjoy activities such as
swimming, boating, and fishing on the reservoir.
O Established sustainable, effective partnerships. The cooperation among partners
at all levels, including UDEQ, JTAC, local communities, conservation districts, water
suppliers, and watershed groups, have established a strong foundation for maintaining
the water quality of Deer Creek Reservoir and addressing future issues.
SEPA
December 2009 • EPA841-F-09-0020
For more information on the Deer Creek Reservoir phosphorus TMDL, contact
Dave Wham, Utah Department of Environmental Quality, dwham@utah.gov, (801) 538-6052
For more information on the Utah TMDL Program, visit www.waterquality.utah.gov/TMDL/
Deer Creek-5
------- |