U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
BLACK BAYOU ESERVOIR
CADDO PARISH
LOUISIANA
EPA REGION VI
WORKING PAPER No, 530
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•&G.P.O. 699-440
-------
REPORT
ON
BLACK BAYOU RESERVOIR
CADDO PARISH
LOUISIANA
EPA REGION VI
WORKING PAPER No, 530
WITH THE COOPERATION OF THE
LOUISIANA WILD LIFE AND FISHERIES COMMISSION
AND THE
LOUISIANA NATIONAL GUARD
MARCH, 1977
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REPORT ON BLACK BAYOU RESERVOIR
CADDO PARISH, LOUISIANA
EPA REGION VI
by
National Eutrophication Survey
Water and Land Monitoring Branch
Monitoring Applications Laboratory
Environmental Monitoring & Support Laboratory
Las Vegas, Nevada
and
Eutrophication Survey Branch
Corvallis Environmental Research Laboratory
Corvallis, Oregon
Working Paper No. 530
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
March 1977
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CONTENTS
Page
Foreword i i
List of Louisiana Study Lakes iv
Lake and Drainage Area Map v
Sections
I. Conclusions 1
II. Lake and Drainage Basin Characteristics 4
III. Lake Water Quality Summary 6
IV. Nutrient Loadings 13
V. Literature Reviewed 19
VI. Appendices 20
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11
FOREWORD
The National Eutrophicatlon Survey was Initiated 1n 1972 in
response to an Administration commitment to investigate the nation-
wide threat of accelerated eutrophication to freshwater lakes and
reservoirs.
OBJECTIVES
The Survey was designed to develop, in conjunction with state
environmental agencies, information on nutrient sources, concen-
trations, and impact on selected freshwater lakes as a basis for
formulating comprehensive and coordinated national, regional, and
state management practices relating to point source discharge
reduction and nonpoint source pollution abatement in lake water-
sheds.
ANALYTIC APPROACH
The mathematical and statistical procedures selected for the
Survey's eutrophication analysis are based on related concepts
that:
a. A generalized representation or model relating
sources, concentrations, and Impacts can be
constructed.
b. By applying measurements of relevant parameters
associated with lake degradation, the generalized
model can be transformed into an operational
representation of a lake, its drainage basin, and
related nutrients.
c. With such a transformation, an assessment of the
potential for eutrophication control can be made.
LAKE ANALYSIS
In this report, the first stage of evaluation of lake and
watershed data collected from the study lake and its drainage
basin is documented. The report is formatted to provide state
environmental agencies with specific information for basin
E Tanning [§303(e)], water quality criteria/standards review
§303(c)], clean lakes [§314(a,bj], and water quality monitoring
[§106 and §305(b)] activities mandated by the Federal Water
Pollution Control Act Amendments of 1972.
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m
Beyond the single lake analysis, broader based correlations
between nutrient concentrations (and loading) and trophic condition
are being made to advance the rationale and data base for refine-
ment of nutrient water quality criteria for the Nation's freshwater
lakes. Likewise, multivariate evaluations for the relationships
between land use, nutrient export, and trophic condition, by lake
class or use, are being developed to assist in the formulation of
planning guidelines and policies by the U.S. Environmental Protection
Agency and to augrrent plans implementation by the states.
ACKNOWLEDGMENTS
The staff of the National Eutrophication Survey (Office of
Research and Development, U.S. Environmental Protection Agency)
expresses sincere appreciation to the Louisiana Iv'ild Life and
Fisheries Commission, Division of Water Pollution Control for
professional involvement, to the Louisiana National Guard for
conducting, the tributary sampling phase of the Survey, and to
those Louisiana wastewater treatment plant operators who pro-
vided effluent samples and flow data.
Robert A. Lafleur, Chief; J. Dale Givens, Assistant Chief;
Lewis P.. Still, Biologist; Louis Johnson, Biologist; Lee Cau-
barreaux, Biologist; Darrell Reed, Engineer; Dempsey AT ford,
Biologist; and Elwood Goodwin, Water Quality Control Technician,
all of the Louisiana Wild Life and Fisheries Commission, Division
of Water Pollution Control reviewed the preliminary reports and
provided critiques most useful in the preparation of this
Working Paper Series.
Major General O'Meil Daigle, Jr., the Adjutant General of
Louisiana, and Project Officer Colonel Lawrence P. Dupre, who
directed the volunteer efforts of the Louisiana National Guards-
men, are also gratefully acknowledged for their assistance to
the Survey.
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IV
NATIONAL EUTROPHICATION SURVEY
STUDY LAKES
STATE OF LOUISIANA
LAKE NAME
Anacoco Lake
Lake Bistineau
Black Bayou
Black Lake
Bruin Lake
Bundicks Lake
Caddo Lake
Cocodrie Lake
Cocodrie Lake (Lower)
Concordia Lake
Cotile Lake
Cross Lake
D'Arbonne Lake
False River Lake
Indian Creek Reservoir
Saline Lake
Turkey Creek Lake
Lake Vernon
Lake Verret
PARISH
Vernon
Bienville, Webstei?
Caddo
Natchitoches and Red River
Tensas
Beauregard
Caddo (Menon and Harrison
in Texas)
Concordia
Rapides
Concordia
Rapides
Caddo
Union
Pointe Coupee
Rapides
LaSalle
Franklin
Vernon
Assumption
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I
94'10'
I
94'00
f\ Louisiana
^i
Map Location
3310-
Capps [ LOUISIANA
o City
BLACK BAYOU LAKE
® Tributary Sampling Site
X Lake Sampling Site
y Sewage Treatment Facility
^"\ Drainage Area Boundary
jMi.
Scale
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REPORT ON BLACK BAYOU RESERVOIR, LOUISIANA
STORE! NO. 2204
1. CONCLUSIONS
A. Trophic Condition:*
On the basis of Survey data and field observations,
Black Bayou Reservoir is considered eutrophic, i.e., nu-
trient rich and highly productive. Whether such nutrient
enrichment is to be considered beneficial or deleterious
is determined by its actual or potential impact upon
designated beneficial water uses of each lake.
Chlorophyll a^ levels ranged from 2.8 yg/1 in the fall
to 47.0 Mg/1 in August with a mean of 17.8 pg/1. Potential
for primary production as measured by algal assay control
yield was high, and Secchi disc transparency was low. Of
the 19 Louisiana lakes sampled in 1974, 13 had greater
median total phosphorus, 13 had greater median inorganic
nitrogen, and 15 had greater median orthophosphorus levels
than Black Bayou Reservoir.
Field limnologists reported abundant aquatic macro-
phytes along the lake bottom and shoreline area. Other
studies (Shampine, 1971) indicate that past pollution to
Black Bayou Reservoir from oil field wastes appears to
have presently been curtailed. The general water quality
*See Appendix E.
-------
in Black Bayou Reservoir appears to range widely, both with
respect to areas within the lake and the time of year.
B. Rate-Limiting Nutrient:
Mean inorganic nitrogen to orthophosphorus ratios (N/P) for
the reservoir were 9/1 or less on all four sampling occasions
suggesting primary limitation by nitrogen.
C. Nutrient Controllability:
1. Point sources -
The mean annual phosphorus load from point sources was
estimated to be approximately 13.4% of the total load reaching
Black Bayou Reservoir. The city of Vivian contributed this
entire point source load.
2
The phosphorus loading of 1.07 g P/m /yr for Black Bayou
Reservoir is approximately 1.6 times the "eutrophic" load
proposed by Vollenweider (1975) for lakes with such volume
and detention time. Although elimination of the Vivian point
source contributions would substantially reduce loading to
the lake, concurrent control of nonpoint sources in the Black
Bayou watershed is probably necessary to effect significant
water quality improvement.
-------
2. Nonpoint sources -
The mean annual phosphorus load from nonpoint
sources was estimated to be 81.6% of the total load.
Measured tributaries accounted for 62.5% of the
total, and ungaged tributaries were estimated to
account for 17.3%.
In general, few lakes are nitrogen limited as
a result of low nitrogen. Rather, excessive
phosphorus levels shift limitations to nitrogen
or other factors. Reqardless of the primary nutrient
limitation suggested by either algal assay or nutri-
ent ratios, the most feasible approach to nutrient
control, if desirable, is through available phospho-
rus control technology and subsequent establishment
of phosphorus limitation within the water body.
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II. LAKE AND DRAINAGE BASIN CHARACTERISTICS
Lake and drainage basin characteristics are itemized
below. Lake surface area and mean depth were provided by
the State of Louisiana; maximum depth was obtained from
contour maps provided by the Louisiana Stream Control Com-
mission; tributary flow data were provided by the Louisiana
District Office of the U,S. Geological Survey (USGS)(outlet
drainage area includes the lake surface area). Mean
hydraulic retention time was obtained by dividing the lake
volume by mean flow of the outlet. Precipitation values
are estimated by methods as outlined in National Eutrophication
Survey (NES) Working Paper No. 175. A table of metric/English
conversions is included as Appendix A.
A. Lake Mbrphometry:
p
1. Surface area: 16.06 km ..
2. Mean depth: 1.4 meters.
3. Maximum depth: 2.4 meters.
4. Volume: 21.956 x TO6 m3.
5. Mean hydraulic retention time: 37 days.
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B. Tributary and Outlet (see Appendix B for flow data):
1. Tributaries -
Drainage Mean flow
Name area(km2) (m3/sec)
A-2 Black Bayou 295.3 3.37
D-l State Line Creek 139.6 1.59
E-l Gray Branch 16.2 0.18
Minor tributaries and
immediate drainage - 141.9 1.80
Totals 593.0 6.94
2. Outlet - A-l Black Bayou 608.6 6.94
C. Precipitation:
1. Year of sampling: 154.3 cm.
2. Mean annual: 117.8 cm.
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III. LAKE WATER QUALITY SUMMARY
Black Bayou Reservoir was sampled four times during the
open-water season of 1974 by means of a pontoon-equipped Huey
helicopter. Each time, samples for physical and chemical
parameters were collected from three stations on the lake
and from one or more depths at each station (see map, page v).
During each visit, depth-integrated samples were collected
from each station for chlorophyll a^ analysis and phytoplankton
identification and enumeration. During the first and last visits,
18.9-liter depth-integrated samples were composited for algal
assays. Maximum depths sampled were 1.8 meters at Station 01,
2.4 meters at Station 02, and 1.5 meters at Station 03. For a
more detailed explanation of NES methods, see NES Working
Paper No. 175.
The results obtained are presented in full in Appendix C
and are summarized in III-A for waters at the surface and at
the maximum depth for each site. Results of the. phytoplankton
counts and chlorophyll a^ determinations are included in III-B.
Results of the limiting nutrient study are presented in III-C.
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BLACK tJAt".;U
STO-'ET COOt i>?C»4
( 3/2J/7* )
•N* HMNGE MEDIAN
PHYSICAL AMD CHEMICAL CHARACTEKISTICS
( 6/ 3/74 )
MAX MftX
PfcPTr! S*»* = 3 DEPTH
RANGE MANGE
(METERS) N» KANGE MEDIAN (METERS) N»
( 8/26/7*
S»»* = 3
RANGE MEDIAN
MAX
DEPTH
i (METtKS)
TtN'Pdf A TUNE (Uc'3 CENT)
d.-l.S M DEPTH
MAX Uf-'PTh**
DISSOLVED 0«.YGEN
0.-1.5 X UEPTn
MAX DEPTH**
CONDUCTIVITY (UMHI
0.-1.5 M DEPTH
MAX DEPTH**
3
3
(MG/L)
2
3
0*)
3
3
16.2- 16.7
16.2- 16.7
3.2- 8.0
3.2- 8.6
167.- 232.
168.- 232.
16. »
16.3
5.6
8.0
169.
169.
0.0-
n.o-
0.0-
0.0-
0.0-
0.0-
0.0
2.4
0.0
2.4
0.0
2.4
4
3
3
3
4
3
25.6- 27.4
25.6- 27.4
3.4- 7.0
3.4- 7.0
152.- 292.
152.- 292.
26.7
26.4
4.4
4.4
222.
239.
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
1.5
1.5
1.5
1.5
1.5
1.5
<4
3
3
?
4
3
29.1- 29.6 ?9.1
2V. 1- 29.6 29.1
3.0- 5.6 3.8
3.tt- 5.6 4.7
130.- 266. 139.
136.- 266. 141.
0.0- 1.5
0.0- l.S
0.0- 0.0
0.0- 0.0
0.0- 1.5
0.0- 1.5
PH (STANDARD UNITS)
0.-1.5 M DEPTH
MAX DEPTH*'
TOTAL ALKALINITY
0.-1.5 M DEPTH
MA* DEPTH**
TOIAL P (MG/L)
0.-1.5 M DEPTH
MAX DEPTH**
DISSOLVED OrfTHO P
O.-l.S M DEPTH
MAX DEPTH**
0.-1.5 M DEPTh
MAX DEPTH**
AMMONIA (M(i/L>
0.-1.5 i* DEPTH
MAX DEPTrl**
KJELO&HL N (MG/L)
O.-l.S M DEPTH
MAX DtPTH**
3
3
(MG/L)
3
3
3
3
(MG/L)
3
3
3
3
3
3
3
3
6.0- 6.7
6.0- 6.7
10.- 11.
10.- 11.
0.024-0.225
0.026-0.225
0.008-0.070
0.008-0.070
0.0?0-0.090
0.020-0.090
0.030-0.210
0.030-0.210
0.500-0. BOO
0.500-0. 800
6.4
6.3
10.
10.
0.030
0.030
0.009
0.009
0.030
0.030
0.030
0.030
0.700
o. loo
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0
2.4
0.0
2.4
O.U
2.4
0.0
2.4
0.0
2.4
0.0
2.4
0.0
2.4
4
3
4
3
4
3
4
3
4
3
4
3
4
3
6.7- 8.7
6.7- 7.5
10.- 13.
10.- 13.
0.042-0.134
0.046-0.134
0.003-0.015
0.003-0.015
0.020-0.030
0.0*0-0.030
0.040-0.130
0.040-0.130
0. 600-0. HOO
o. 600-0. aoo
7.3
7.0
10.
10.
0.048
0.050
0.008
0.013
0.025
0.030
0.040
0.040
0.600
0.600
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
0.0-
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
l.b
1.5
1.5
3
2
0
0
0
0
0
0
0
0
0
0
0
0
7.0- 7.0 7.0
7.0- 7.0 7.0
00000-0000* »*«»«
00000-0*00* »»*«»
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ooooo-ooooo ooooo
00000-000*0 *oooo
ttooeo-eoooo ooooo
ooooo-ooooo 000*0
ooooo-ooooo *oooo
ooooo-oeoo* ••»»•
oeooo_o»ooo 000*0
ooooo-ooooo ooooo
eoooo-oooeo ooooo
0.0- 0.0
0.0- 0.0
0*00-00*00
0*00-000*0
**oo_ooooo
oooo-ooooo
«*00-00000
•ooo-ooooo
«000-0*000
••00-00*00
*«oo. 00*00
•000-00000
oooo-ooooo
**oo_o***»
SECCHI DISC
1.4- 2.1
l.b
0.8- 0.9
0.8
0.7- 1.1
O.U
» N = NO. OF SAMPLES
** MAXIMUM DtPTrl SAMPLED AT EACH
*»« s = NO. OF SITES SAMPLED ON THIS DATE
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HLAC* >jAYO'j
STC-Ef C<.,UE 2? 04 PHYSICAL AND ChE"ICAL
( 11/11/7-* )
"AX
•,OiKJ = T fJEPfH
rtfcOI AN
TEMPtVAT'J-t (O.-.ii C"...!)
0.-1.5 - uErFH r> 15.3- 15.y 15.7 0.0- 1.5
«AX uEPTrf«» 3 15.3- 1 b. d 1^.7 :}.0- 1.5
OISSOL^ii) U*Y'-t'fi (Mo/L.I
0.-1.5 M liE(-'TH 5 2.H- 6.0 4.b n.O- 1.5
»« 3 2.o- 6.0 4,fc 0.0- 1.5
CONUUCTlVlTf (Uw-iO^I
0.-1.3 »i OEPTH 5 99.- 170. 145. 0.0- 1.5
> 3 99.- 1^0. 145. 0.0-1.5
5 5.6- 6.1 5.0 0.0- 1.5
3 5.6- 6.1 5.6 0.0- 1.5
TOTAL ALKALINITY IM'G/L)
0.-1.5 « OE-'TH S 10.- 15. in. 0.0- 1.5
MAX DEPTH** 3 10.- 10. 10. 0.0- 1.5
TOTAL P («G/L)
O.-l.ri M ijEPTn 5 0.0 .U-0.266 0.053 0.0- 1.5
3 0.034-0.266 0.061 0.0- 1.5
DISSOLVED O^THO y IMR/L)
O.-l.l v| OE^Th ^ 0.005-0.092 0.016 0.0- 1.5
MAX OEPTri'-** 3 O.OOe-0.092 0.016 0.0- 1.5
O.-i.S f UE^Tn :> 0.020-0.040 0.0.10 0.0- 1.5
MAX DEPrHa* 3 0.020-0.030 0.030 0.0- 1.5
AMMC.NI"
O.-l.S ». ntfTn 5 0.060-0.630 0.070 0.0- 1.5
MAX DEPTH»» 3 O.OhO-0.630 0.070 0.0- 1.5
0.-1.5 M i.'t''JT'-i 5 0.500-1.^00 0.700 0.0- l.b
VAX DEPTH-** 3 0.500-1.200 0.600 0.0- l.b
SECCHt Ol'^C (••'£FE'-'S)
3 1.1- 1.9 1.1
<* N = NO. OF
»« MAXIMUM DE^TH SAMPLED AT EACH SITE
* s = 'MO. OF SHtb SAMPLED ON THIS UATE
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B. Biological Characteristics:
1. Phytoplankton -
Sampling Dominant
Date Genera
03/22/74 1. Dactylococcopsis
2. Cryptomonas
3. Dinobryon
4. Flagellates
5. Oscillatoria
Other genera
Total
06/03/74 1. Asterionella
2. Aphanothece
3. Flagellates
4. Ankistrodesmus
5. Melosira
Other genera
Total
08/26/74 1. Centric diatom
2. Ankistrodesmus
3. Lyngbya
4. Anabaena
5. Cryptomonas
Other genera
Total
11/11/74 1. Cryptomonas
2. Dactylococcopsis
3. Euglena
4. Oscillatoria
5. Phacus
Other genera
Total
Algal
Units
per ml
611
500
445
445
222
223
2,446
4,802
2,036
1,200
626
418
1,982
11,064
2,007
618
618
463
386
2,973
7,065
220
147
110
37
37
551
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10
2. Chlorophyll a^ -
Sampling
Date
03/23/74
06/03/74
08/26/74
11/11/74
Station
Number
01
02
03
01
02
03
01
02
03
01
02
03
Chlorophyll
(yg/D
6.0
5.3
13.0
24.1
32.1
23.3
23.3
14.5
47.0
4.6
2.8
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked - (03/23/74)
Spike(mg/1)
Control
0.05 P
0.05 P + 1.0 N
1.00 N
Ortho P
Cone.(mg/1)
0.065
0.115
0.115
0.065
Inorganic N
Cone.(mg/1)
0.174
0.174
1.174
1.174
Maximum Yield
(mg/1-dry wt.)
4.1
4.1
27.0
16.6
-------
11
2. Discussion -
The control yield of the assay alga, Selenastrum
capricornuUun, indicates that the potential for primary
production in Black Bayou Reservoir was high at the
time of spring assay sample collection. Growth response
with the addition of nitrogen as well as the lack of
response to the addition of phosphorus indicates nitro-
gen limitation. Maximum growth yield was achieved with
the simultaneous addition of both phosphorus and nitro-
gen.
It should be noted that significant chemical
changes took place in Louisiana lake samples between
collection and algal assay. The assay data should be
considered in this context and until such differences
are resolved, used with caution for any prediction of
actual lake conditions. Such chemical changes are
likely to alter the control yield as well as modifying
the N/P ratio.
The autumn algal assay results have not been
included as the substantial changes in nutrient
levels have removed their information value.
-------
12
The mean N/P ratios for Black Bayou Reservoir of 9/1
or less on all four sampling occasions suggest primary
limitation by nitrogen (an N/P ratio of 14/1 or greater
generally reflects phosphorus limitation).
-------
IV. NUTRIENT LOADINGS
(See Appendix D for data)
For the determination of nutrient loadings, the Louisiana
National Guard collected monthly near-surface grab samples
from each of the tributary sites indicated on the map (page v).
except for the high runoff months of February, March, and
April when two samples were collected. Sampling was begun
in June 1974 and was completed in April 1975.
Through an interagency agreement, stream flow estimates
for the year of sampling and a "normalized" or average year
were provided by the Louisiana District Office of the USGS
for the tributary sites nearest the lake.
In this report, nutrients loads for sampled tributaries
were determined by using a modification of a USGS computer
program for calculating stream loadings. Nutrient loads
indicated for tributaries are those measured minus known
point source loads, if any.
Nutrient loadings for unsampled "minor tributaries and
immediate drainage" ("ZZ" of USGS) were estimated by using the
2
mean annual nutrient loads, in kg/km /yr, for Black Bayou,
State Line Creek, and Gray Branch, at Stations A-2, D-l,
and E-l, respectively, and multiplying the means by the ZZ
area in
-------
14
The operator of the Vivian wastewater treatment
plant provided monthly effluent samples and corresponding
flow data.
A. Waste Sources:
1. Known municipal -
Name
Vivian
Population Mean Flow
Served* Treatment (m^/d x 1
6,000
2.
Known industrial - None
Trickling
Filter
1.751
Receiving
Water
Unnamed
Stream
*U.S. EPA, 1971.
-------
15
B. Annual Total Phosphorus Loading - Average Year:
1. Inputs -
% of
Source kg P/yr total
a. Tributaries (nonpoint load)
A-2 Black Bayou 6,865 39.9
D-l State Line Creek 3,665 21.3
E-l Gray Branch 220 1.3
b. Minor tributaries and immediate
drainage (nonpoint load) - 2,980 17.3
c. Known municipal STP's -
Vivian 3,175 18.4
d. Septic tanks* - 30 0.2
e. Known industrial - none
f. Direct precipitation** - 280 1.6
Totals 17,215 100.0
2. Outputs - A-l Black Bayou 7,985
3. Net annual P accumulation 9,230
*Estimate based on 105 lakeshore residences.
**Estimated (see NES Working Paper No. 175).
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16
C. Annual Total Nitrogen Loading - Average Year:
1. Inputs -
% of
Source kg N/yr total
a. Tributaries (nonpoint load) -
A-2 Black Bayou 90,490 41.9
D-l State Line Creek 47,685 22.1
E-l Gray Branch 5,030 2.3
b. Minor tributaries and immediate
drainage (nonpoint load) - 45,265 21.0
c. Known municipal STP's -
Vivian 9,175 4.2
d. Septic tanks* - 1,120 0.5
e. Known industrial - none
f. Direct precipitation** - 17,340 8.0
Totals 216,105 100.0
2. Outputs - A-l Black Bayou 170,090
3. Net annual N accumulation - 46,015
*Estimate based on 105 lakeshore residences.
**Estimated (see NES Working Paper No. 175).
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17
D. Mean Annual Nonpoint Nutrient Export by Subdrainage Area:
Tributary kg P/km^/yr kg N/km2/yr
Black Bayou 23 306 .
State Line Creek 26 342
Gray Branch 14 310
E. Mean Nutrient Concentrations in Ungaged Streams:
Mean Total P Mean Total N
Tributary (mg/1) (mg/1)
B-l Unnamed Stream 3.702 12.467
C-l Myrtis Mill Creek 0.074 1.035
F-l Horse Creek 0.037 0.692
The nutrient levels in tributaries C-l and F-l were
in line with the measurements in the gaged streams entering
Black Bayou Reservoir. However, nutrient levels for Unnamed
Stream, B-l, were excessively high. This is probably
attributable to the proximity of the tributary sampling
station to the Vivian municipal sewage treatment plant
outfall.
-------
18
F. Yearly Loadings:
In the following table, the existing phosphorus annual
loading is compared to the relationship proposed by Vollenweider
(1975). Essentially, his "eutrophic" loading is that at which
the receiving waters would become eutrophic or remain eutrophic;
his "oligotrophic" loading is that which would result in the
receiving water remaining oligotrophic or becoming oligotrophic
if morphometry permitted. A "mesotrophic" loading would be
considered one between "eutrophic" and "oligotrophic".
Note that Vollenweider's model may not apply to lakes with
short hydraulic retention times or in which light penetration is
severely restricted by high concentrations of suspended solids
in the surface waters.
Total Yearly
Phosphorus Loading
(g/m2/yr)
Estimated loading for Black Bayou Reservoir 1.07
Vollenweider's "eutrophic" loading 0.33
Vollenweider's "oligotrophic" loading 0.67
-------
19
V. LITERATURE REVIEWED
Shampine, W. J. 1971. Chemical, Biological, and Physical
Data for the Major Lakes and Reservoirs in Louisiana.
Louisiana Department of Public Works, #5. Baton Rouge,
Louisiana.
U.S. Environmental Protection Agency. 1971. A 1968
Inventory of Municipal Waste Facilities. EPA Publication
No. OWP-1, Vol. 6, U.S. Government Printing Office,
Washington, DC.
1975. National Eutrophication Survey Methods
1973-1976. Working Paper No. 175. Environmental Monitoring
and Support Laboratory, Las Vegas, Nevada and Corvallis
Environmental Research Laboratory, Corvallis, Oregon.
Vollenweider, R. A. 1975. Input-Output Models With Special
Reference to the Phosphorus Loading Concept in Limnology.
Schweiz. Z. Hydrol. 37:53-84.
-------
20
V. APPENDICES
APPENDIX A
CONVERSION FACTORS
-------
CONVERSION FACTORS
Hectares x 2.471 = acres
Meters x 3.281 = feet
-4
Cubic meters x 8.107 x 10 r acre feet
Square kilometers x 0.3861 = square miles
Cubic meters/sec x 35.315 = cubic feet/sec
Centimeters x 0.3937 = inches
Kilograms x 2.205 = pounds
Kilograms/square kilometer x 5.711 = Ibs/square mile
-------
APPENDIX B
TRIBUTARY FLOW DATA
-------
TRIBUTARY FLOW INFORMATION FOR LOUISIANA
LAKE CODE 2204 BLACK BAYOU LAKE
TOTAL DRAINAGE AREA OF LAKE(SO KM) 608.6
04/11/77
SUB-DRAINAGE
TRIBUTARY AREA(SO KM)
NORMALIZED FLOWS(CMS)
JAN FES MAR APR MAY JUN JUL AUG
SEP
OCT
DEC
MEAN
2204A1
2204A2
2204D1
2204E1
2204ZZ
608.6
295.3
139.6
16.2
158.0
10.39
5.0<»
2.38
0.278
2.69
13.25
6.43
3.03
U.340
3.43
11.86
5.78
2.72
0.311
3.09
14.24
6.91
3.26
0.368
3.71
14.98
7.25
3.43
0.396
3.88
5.30
2.58
1.22
0.142
1.39
1.53
0.74
0.34
0.040
0.40
0.62
0.31
0.14
0.017
0.16
1.02
0.48
0.24
0.028
0.26
1.16
0.57
0.27
0.031
0.31
4.07
2.38
1.19
0.130
1.27
4.62
2.24
1.05
0.122
1.19
6.9<*
3.37
1.59
0.182
1.80
TOTAL DRAINAGE AREA OF LAKE = 608.6
SUM OF SUB-DRAINAGE AREAS = 609.1
MEAN MONTHLY FLOWS AND OAILY FLOWS(CMS)
TRIBUTARY MONTH YEAR
2204A1
MEAN FLOW DAY
FLOW DAY
2204A2
2204D1
6
7
8
9
10
11
12
1
2
3
4
6
7
8
9
10
11
12
1
2
3
4
6
7
8
9
10
11
12
1
2
3
4
74
74
74
74
74
74
74
75
75
75
75
74
74
74
74
74
74
74
75
75
75
75
74
74
74
74
74
74
74
75
75
75
75
SUMMARY
TOTAL FLOW IN = 83.92
TOTAL FLO* OUT = 83.85
FLOW DAY
FLOW
21.804
0.821
0.048
1.557
0.708
11.468
10.194
11.412
37.095
19.963
8.891
10.194
0.396
0.028
0.736
0.340
5.578
5.012
5.522
18.010
9.684
4.304
0.510
0.190
0.011
0.368
0.164
2.633
2.379
2.6C5
8.523
4.587
2.039
8
6
10
7
5
9
6
11
8
7
5
8
6
10
7
5
9
7
11
8
7
5
8
6
10
7
5
9
7
11
8
7
5
84.951
0.074
0.076
0.227
0.170
0.227
0.283
16.509
20.388
11.921
5.947
41.059
0.170
0.034
0.127
0.127
0.425
0.340
8.014
9.883
5.777
2.888
19.539
0.017
0.017
0.051
0.023
0.340
0.283
3.794
4.672
2.747
1.359
18
22
22
19
18
22
22
19
18
22
22
19
0.119
10.675
12.884
6.796
0.113
5.182
6.258
3.285
0.023
2.435
2.945
1.557
-------
TRIBUTARY FLOW INFORMATION FOR LOUISIANA
04/11/77
LAKE CODE 2204
BLACK BAYOU LAKE
MEAN MONTHLY FLO*S AND OAILY FLOWS(CMS)
TRIBUTARY MONTH YEAR MEAN FLOW DAY
2204E1
6
7
8
9
10
11
12
1
2
3
4
74
74
74
74
74
74
74
75
75
75
75
0.595
0.023
0.003
0.042
0.020
0.311
0.283
0.311
0.991
0.538
0.227
8
b
10
7
5
9
7
11
8
7
5
FLOW DAY
3.39fl
0.0
0.0
0.003
O.OC3
0.040
0.028
0.453
0.538
0.311
0.170
Ib
22
22
19
FLO* DAY
0.003
0.283
0.340
0.170
FLOW
-------
APPENDIX C
PHYSICAL"AND CHEMICAL DATA
-------
STCHET RETRIEVAL uftTE 7S/12/11
NATL F_UT«OPlICAT ION
EPA-LAS VEGAS
32 bo 00.0 0^3 SS s7,n
BLACK nAYOu
22 LOUISIANA
DATE TIME 0£PT>-
F«OM OF
TO DAY FEET
74/03/23 09 40 0000
09 40 000?
74/06/03 12 10 0000
12 10 Q005
74/06/26 11 15 OOOn
74/11/11 08 50 0000
08 50
u n n i o
16.4
16.3
27.0
25.6
29.1
15.8
15.8
00300
DO
H.6
3.4
5.6
4.0
4.6
UO(W7 0009-.
T^AMSP CNDUCTVY
SECCHI FIELD
I.MCHLS
84
35
43
45
167
168
23V
141
99
99
lltPALtS
-1
oo«oo
PH
Sn'
6.40
6.25
8.70
6.70
7.00
5.7?
5.62
0041(1
T ALK
CAC03
M*j/L
10K
10<
10K
10K
10K
10K
211
0007
00610
MH3-N
TOTAL
MO/L
0.030
0.030
0.040
0.130
0.070
0.070
12
OO'-Vb
TOT KJEL
N
MP/L
O.oOO
0.50U
O.oOO
0.600
0 . fj 0 0
0.600
Tt-
0063U
NO
-------
HET3IE.VAL UA
NATl. F.uT-fO-'HlCAT IG';
\/?G»S
75/12/11
3? n3 10.0 0^3 b? 26.0
BLACK tiAYOU
22 LOUISIANA
DATE
FROM
TO
74/03/23
74/06/03
74/06/26
74/11/11
OATE
FROM
TO
74/03/23
74/06/03
74/08/26
74/11/11
TIME OEPT"
OF
DAY FEET
09 50 0000
12 25 0000
11 30 0000
09 10 OOOn
TIME DEPTH
OF
DAY FEET
09 50 0000
12 25 0000
12 25 0001
12 25 0005
11 30 0000
09 10 0000
0001 0
WATER
TtMf-
CENT
16.2
26.4
29.6
15.3
00665
PrlOS-TOT
MG/L P
0.225
0.134
0.266
00"»00
00
MG/L
3.2
4.4
3.8
2.8
32217
ChLHPHYL
A
UG/L
13.0
23.3
47.0
0 0 077
ThANSP
StCCnl
iNCntS
54
32
26
45
00031
INCDT LT
HEMNING
PEHCENT
50.0
1.0
00094
CNDUCTVY
FIELD
MJCrJUMhU
232
292
266
170
3
00400
6.05
7.00
7.00
5.75
0006 FEtT
00*10
T ALK
CAC03
MG/L
11
13
00610
Nrl3-i\
TOTAL
MG/L
0.210
0.040
00*
TOT «
N
f b/l
0.'
O.I
UOIS30
10*
0.630
N-TOTflL
MG/L
0.090
0.020
0.030
00&71
PHOS-OIS
MU/L P
0.070
O.Olb
K VALUE KNOWN TO BE LESS THAN
INDICATED
-------
APPENDIX D
TRIBUTARY AND WASTEWATER
TREATMENT PLANT DATA
-------
Si'ORET RETRIEVAL OATt 77/04/il
/T'PA/AMBNT/STREAM
2204A1
32 52 55.0 093 53 50.0 4
CJLACK BArOu
22 7.5 VIVIAN N
0/dLACK 8AYOU LAKE 101691
LA riwY 2 A ING DAM
11EPALES 04001004
COOO FEET DEPTH CLASS 00
DATE
FROM
TO
74/06/08
74/07/06
74/08/10
74/09/07
74/10/05
74/10/18
74/1 1/09
74/12/06
75/01/11
75/02/08
75/02/22
75/03/07
75/03/22
75/04/05
75/04/19
00630 00625
TIME DEPTH N02*>N03 TOT KJFL
OF N-TOTAL N
DAY FEET
09
10
13
11
20
09
11
07
07
07
09
08
10
08
25
05
00
15
03
on
30
00
30
35
?5
30
00
10
MG/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.004
.064
.208
.032
.03?
.032
.02t
.040
.008
.032
.008
.016
.009
.005
.005
MG/L
0.
1.
1.
o.
0.
0.
0.
0.
0.
0.
0.
1.
0.
0.
0.
700
300
200
700
400
soo
700
500
600
600
500
050
400
300
650
00610 00671 00665
NH3-N PHOS-OIS PHOS-TOT
TOTAL ORTHO
MG/L
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
010
100
280
050
045
035
140
070
040
072
032
024
015
025
020
MG/L P
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.010
.020
.015
.005
.010
.010
.020
.015
.015
.005K
.008
.008
.005
.005
.005K
MG/L P
0.040
0.110
0.070
0.025
0.025
0.025
0.030
0.050
0.030
0.050
0.040
0.040
0.030
0.010K
0.020
K VALUE KNOWN TO BE
LESS THAN INDICATED
-------
STORET RETRIEVAL OAT;, 77/04/11
/TYDA/AX9NT/STREAM
DATE TIME DEPTH NO?\N03
FROM OF
TO DAY FEET
74/06/08
74/07/06
74/08/10
74/39/07
74/10/05
7<»/10/18
74/11/09
74/12/07
75/01/11
75/02/08
75/02/22
75/03/07
75/03/22
75/04/05
75/04/19
11 SS
09 30
11 45
09 20
14 ?0
16 50
09 45
09 10
09 40
10 45
09 30
10 10
09 45
09 05
08 15
2204A2
32 58 30.0 094 01 tO.O 4
*LACK BAYOU
22 7.5 MCLEOO
T/flLACK riAYOU LAKE 101691
LA HWY 168 HROG 2 HI * OF ROOtSSA
11EPALES 0400100<»
0000 FEET DEPTH CLASS 00
0630
AN03
OTAL
iG/L
0.092
0.084
0.080
0.068
0 . 1 36
0.032
0.008
0.032
0.056
C.016
0.024
0.046
0.009
0.065
0.105
00625
TOT KJEL
M
HG/L
0.7?0
0.600
0.650
0.700
0.600
0.550
0.600
2.900
0.800
0.400
0.700
l.OOC
0.600
1.000
1.300
00610
NH3-N
TOTAL
MG/L
O.J30
0.065
C.045
0.045
0.290
0.020
0.0?5
0.032
0.044
0.024
C.032
0.016
0.010
0.040
0.090
00671
pHOS-nts
ORTHO
MG/L P
0.025
0.035
0.020
0.050
0.045
0.055
0.045
0.030
0.030
0.032
O.C32
0.032
0.022
O.Q4Q
0.045
00665
PHOS-TOT
MG/L r3
0.025
0.110
0.072
0.075
0.080
0.100
0.070
0.050K
0.080
0.050
0.090
0.070
0.060
0.060
0.100
K VALUE KNOWN TO 6E
LESS THAN INDICATED
-------
STDRET RETRIEVAL OATE 77/04/11
OATE TIME DEPTH N026.N03
FROM OF
TO DAY FEET
74/06/08
74/07/06
74/08/10
74/09/07
74/10/05
74/10/18
74/11/09
74/12/Q7
75/01/11
75/02/08
75/02/22
75/03/07
75/03/22
75/04/05
75/04/19
08 55
08 40
12 25
08 35
09 05
19 03
08 45
09 30
10 00
11 15
09 45
11 45
10 10
09 45
09 05
2?04di
32 52 40.0 093 58 15.0 4
UNNAMED STREAM
22 7.6 VIVIAN N
T/8LACK tiAYOU LAKE 101691
6NK DOWNSTREAM FROM VIVIAN STP OUTFALL
11EPALES 040010C4
0000 FEET OEPTM CLASS 00
063U
'6.N03
OTAL
IG/L
C.600
1.512
1.840
1.70C
1.360
l.?40
1.0^0
1.240
0.800
0.950
0.690
0.528
0.635
0.510
0.720
00625
TOT KJEL
N
Md/L
5.500
25.000
22.000
13.500
26.000
14.000
9.600
3.100
6.200
6.000
8.300
5.500
9.900
5.100
00610
NH3-N
TOTAL
MG/L
1.300
".100
8.600
6.200
3.300
3.800
1.000
0.780
0.552
0.760
0.650
0.588
1.720
?.ooo
00671
PHOS-OIS
OrtTHO
MG/L P
0.695
8.600
10.500
5.500
5.600
0.650
2.000
0.525
0.550
0.464
0.800
0.040
0.5S8
0.950
0.775
00665
PHOS-TOT
MG/L P
1.600
10.500
11.500
6.000
0.800
3.200
0.740
1.900
1.650
2.800
1.330
1.800
4.300
-------
STOSET RETRIEVAL 2ATF 77/04,'
22GHC1
32 55 50.0 093 59 35.0 t
nr^TIS MILL MEEK
22 7.5 VIVIAN N
T/iLACK BAtOU LAisE 1
LA HWC 1 HHOG 0.4 MI S Li MWY 769 JCT
HFPaLES 0^00100'.
0000 FEET DEPTH CLASS 00
•JATE
FROM
TO
74/06/08
74/07/06
74/08/10
74/09/07
74/10/05
74/10/18
74/11/09
74/12/07
75/02/OH
75/02/22
75/03/07
75/03/22
75/04/05
75/04/19
U0630
TIME DEPTH M02t.M03
OF
OAV FEET
10 ?5
09 1=;
12 15
09 05
10 40
18 31
09 00
08 40
11 10
09 00
10 07
09 15
09 25
08 ?5
N-TOTAL
Mu/L
0.076
0.018
0.092
0.056
0.040
0.024
0.008
0.032
0.030
0.016
0.024
0.012
0.025
0.030
00625
TOT KJEL
N
MG/L
1.100
1.500
0.800
1.000
2.600
O.(?00
0.500
0.500
0.400
1.400
0.750
0.450
1.400
0.800
00610
N-o-U
TOTAL
MG/L
0.070
0.185
C.100
d.085
0.15U
0.190
0.030
0.025
O.C65
0.048
0.032
0.024
0.050
0.090
00671
PrlOS-OIS
O.^TnO
MG/L f> MG/L
00665
PHOS-TOT
0.025
0.030
0.030
0.025
0.055
0.030
0.025
0.010
0.003
0.015
0.015
0.010
0.025
0.025K
0.210
0.090
0.035
0.080
0.205
0.040
0.030
0.030
0.040
0.030
0.040
0.040
0.040
K VALUE KiMOw.N ro at
LESS THAN INDICATED
-------
CVAL CATP" ?7/0-*/H
220401
32 58 25.0 094 01 20.0 4
STATt LIME CKt'EK
22 7.5 MCLEOO
T/8LACK 6AYOU LAKE
LA rlWY 168 3POG 1.5 MI
11EPALES
0000 FEET DEPTn
101691
w OF RODESSA
C400100t
CLASS 00
DATE
FROM
TO
74/06/08
74/07/06
74/08/10
74/09/07
74/10/05
74/10/18
74/1 1/09
74/12/07
75/01/11
75/02/08
75/03/07
75/33/2?
75/04/05
75/04/19
00630 006P5
TIME DEPTH N026N03 TOT KJEL
OF N-TOTfiL N
L)A1
11
09
11
09
13
15
09
09
09
10
10
09
09
08
' FEET
40
34
47
?5
Ifl
30
35
05
35
40
05
40
00
30
00610 09671 00665
NM3-N PHOS-OIS PHOS-TOT
TOTiL 0*THO
'••IG/L MG/L MI.,/L
0
3
c
c
0
c
•D
o
0
0
0
0
c
0
.030
.092
.02d
.052
.080
.024
.003
.032
.045
.016
.040
.0?2
.070
.100
0.
0.
1.
0.
0.
c.
2.
0.
0.
0.
0.
0.
0.
0.
600
600
800
900
800
650
COO
400
400
400
700
800
600
900
0.
3.
0.
0.
c.
0.
0.
5.
0.
0.
0 .
0.
0.
0.
050
050
045
030
035
030
075
020
048
028
035
035
050
105
MG/L P
0
c
0
0
0
0
0
0
0
0
0
0
0.
0
.030
.085
.010
.050
.045
.055
.050
.020
.032
.005K
.032
.024
.040
.035
MG/L r>
0.070
0.175
0.055
0.085
0.100
0.090
0.040
0.060
0.050
0.090
0.070
O.U60
0.070
K VALUE KNOWN TO at
LESS THAN INDICATED
-------
32 57 30.0 093 56 07.0
CrfAY dRANCH
22 7.5 VIVIAN M
T/dLACrt BArOU LAKE
2.NORY RD dHDG 2 MI
11E&ALES
0000 F££T (
101691
SE Of7 ROOESSA
04001004
CLASS 00
DATE
FPOM
TO
7^/06/08
74/07/06
74/08/10
74/09/07
74/10/05
74/ld/lR
74/1 I/OS
74/12/07
75/01/11
75/02/08
75/02/2?
75/03/07
75/03/2?
75/04/05
75/04/19
00630 0062S
TIMF DEPTH N02NN03 TOT KJEL
OF N- TOTAL N
OAf FEET
10
09
12
09
12
19
09
08
09
11
09
09
09
09
08
50
45
30
30
05
•»o
?.o
S5
25
00
10
?5
30
15
=50
MG/L
vl
0
0
0
r,
- ,~i
0
0
0
0
0
0
Vs
0
0
.080
.020
.032
.040
.040
.0?"
.016
,C16
.024
.032
.032
.032
.01*
.020
.030
MG/L
0.
0.
2.
0.
0.
0.
0.
0.
1.
1.
0.
0.
1.
0.
0.
700
POO
200
700
600
400
000
eoo
000
100
600
900
250
600
850
0-J610 00671 00665
NM3-N PnOS-OIS PHOS-TOT
TOT4L OKTnU
Mr-XL
0.
0.
j .
c.
•1 .
').
0.
0.
0.
0.
0.
0.
0.
0.
0.
035
350
910
115
143
055
?30
C65
120
064
088
060
062
105
160
MG/L
0.
0.
0.
0.
0.
C.
0.
C.
0.
0.
0.
I).
0.
0.
0.
k
040
010
050
005
015
010
020
010
030
032
016
008
009
005
010
M'j/L i3
0.095
0.030
0.120
0.015
0.020
0.015
0.020
0.030
0.040
0.032
0.030
0.030
0.080
0.020
0.020
-------
WET-UE'/AL OATF 77/O/Jl
DATE TIME DE0!-! N02S
FROM Or
TO DAY FEET
74/06/08
74/07/06
74/08/10
74/09/07
7^/10/05
74/10/18
74/11/09
74/13/07
75/01/11
75/02/OB
75/02/23
75/03/07
75/03/2?
75/04/05
75/04/19
10 40
09 SO
12 10
09 35
11 10
19 15
09 15
08 50
09 ?0
11 05
09 05
09 30
09 ?5
09 ?0
09 55
2204F1
32 57 30.0 093 57 10.0 4
HO^SE CREtK
22 7.5 VIVIAN IM
T/tJLACK BAYOU LA*E 101691
2MORY PO 6KD13 3 Ml SE OF rtOUESSA
llEPALtTS 04001004
0000 FEET OtPTn CLASS 00
J0630
?SN03
fOTAL
10 /L
0.02-3
0.030
0.020
C.0^8
0.044
:).04«
0.00^
0.016
0.016
C.024
0.040
0.016
0.015
0.010
0.010
00625
TOT K.JEL
^J
MG/L
0.690
0.800
0.700
0.500
0.500
0.400
0.850
0.600
0.500
0.800
0.900
0.500
0.650
0.900
C0610
NH3-N
TOTAL
MG/L
0.030
0.060
0.055
0.027
C.035
0.037
0.060
0.045
0.024
0.032
0.088
:l . 0 1 6
0.022
0.035
O.C90
00671
PHOS-DIS
ORTHO
MG/L P
0.025
0.025
C.C25
0.015
0.010
0.010
O.U20
0.010
0.015
0.008
0.032
0.008
0.009
0.010
0.030
00665
PHOS-TOT
MG/L P
0.025
0.070
0,085
0.030
0.02C
0.025
0.030
O.C20
0.020
0.020
0.080
0.040
0.030
0.020
-------
APPENDIX E
PARAMETRIC RANKINGS OF LAKES
SAMPLED BY NES IN 1973
STATE OF
LOUISIANA
-------
UAKE DATA TO BE USED IN RANKINGS
LAKE
CODE LAKE NAME
3201 ANACOCO LAKE
2202 ORUINi LAKE
2203 LAKE BISTINEAU
2204 BLACK BAYOU
2205 BUNDICK LAKE
2207 COCODRIE LAKE
?208 COTILE LAKE
2209 CONCOHDIA LAKE
2210 CROSS LAKE
2211 O'ARBONNE LAKE
2212 FALSE RIVER LAKE
2213 INDIAN CREEK
2214 SALINE LAKE
2215 TURKEY CREEK LAKE
2216 LAKE VERRET
2217 LAKE VERNON
2219 BLACK LAKE
2220 COCODRIE
4807 CADDO LAKE
MEDIAN
TOTAL P
0.031
0.057
0.061
0.046
0.157
0.090
0.037
0.076
0.057
0.036
0.082
0.031
0.111
0.176
0.163
0.018
0.077
0.106
0.049
MEDIAN
INORG N
0.080
0.250
0.100
0.090
0.135
0.400
0.100
0.080
0.080
0.100
0.130
0.150
0.350
0.170
0.100
0.120
0.150
0.050
0.070
500-
MEAN SEC
455.833
450.333
458.000
453.417
469.667
479.000
442.333
468.333
475.250
458.250
442.500
458.333
493.000
477.833
481.428
436.667
454.000
478.333
463.562
MEAN
CHLOHA
8.700
16.350
12.933
17.818
20.467
35.300
12.650
32.950
38.385
6.800
. 24.550
21.467
15.333
21.967
62.028
4.900
12.733
33.433
20.125
15-
MIN no
10.400
15.000
13.200
12.200
10.600
7.700
14.000
14.800
11.400
13.200
14.900
14.800
9.600
14.600
12.000
14.400
11.600
11.800
10.000
MEDIAN
OISS ORTHO P
0.007
0.012
0.018
0.009
0.073,
0.026
0.011
0.009
0.010
0.011
0.023
0.010
0.02.5
0.033
0.056
0.007
0.015
0.014
0.008
-------
PERCENT OF LAKES WITH HIGHER VALUES (NUMBER OF LAKES WITH HIGHER VALUES)
LAKE
CODE LAKE NAME
2201 ANACOCO LAKE
2202 BRUIN LAKE
2203 LAKE BISTINEAU
2204 BLACK BAYOU
2205 BUNOICK LAKE
2207 COCODRIE LAKE
2208 COTILE LAKE
2209 CONCOROIA LAKE
2210 CROSS LAKE
2211 D'ARBONNE LAKE
2212 FALSE RIVER LAKE
2213 INDIAN CREEK
2214 SALINE LAKE
2215 TURKEY CREEK LAKE
2216 LAKE VERRET
2217 LAKE VERNON
2219 BLACK LAKE
2220 COCODRIE
4807 CAODO LAKE
MEDIAN
TOTAL P
92
61
50
72
11
28
83 <
44 i
56 i
78 i
33 1
92 1
17 1
0 1
6 1
100 1
39 (
22 1
67 1
( 16)
( 11)
( 9)
( 13)
I 2)
t 5)
I 15)
I 8)
I 10)
I 14)
! 6)
! 16)
; 3)
[ 0)
I 1)
: is)
i 7)
! 4)
! 12)
MEDIAN
INOPG N
93
11
58
72
33
0
58 i
83 i
83 i
58 i
39 1
28 1
6 I
17 1
58 1
44 1
22 <
100 1
94 1
( 14)
( 2)
( 9)
( 13)
( 6)
( 0)
I 9)
1 14)
t 14)
t 9)
! 7)
I 5)
I 1)
I 3)
I 9)
I 8)
: 4)
1 18)
1 17)
500-
MEAN SEC
67
83
61
78
33
11
94
39
28
56
89
50
0 i
22 i
6 l
100 1
72 1
17 1
44 i
( 12)
( 15)
( 11)
( 14)
( 6)
( 2)
( ,17)
( 7)
( 5)
( 10)
1 W>
( 9)
I 0)
I 4)
1 1)
1 18)
t 13)
I 3)
! 8)
MEAN
CHLORA
39 1
61 1
72 1
56 1
44 1
11 1
83 (
22 <
6 (
94 (
28 <
39 (
67 (
33 (
0-.(
100 (
78 (
17 <
50 (
I 16)
! 11)
I 13)
[ 10)
! 8)
[ 2)
: is)
: 4)
1)
17)
5)
7)
12)
6)
0)
18)
14)
3)
9)
15-
MIN 00
83
0
42 '
50 i
78 i
100 l
33 1
14 1
72 1
42 1
6 1
14 I
94 <
22 (
56 (
28 (
67 (
61 (
89 I
( 15)
I 0)
I 7)
I 9.)
I 14)
I 18)
I 6)
I 2)
1 13)
[ 7)
: l J
2)
: 17)
4>
10)
5)
12)
11)
16)
MEDIAN
DISS ORTHO P
94
50
33
81
0 i
17 i
61 1
81 1
ft? '
56 1
28 1
•69 (
2? <
11 <
6 <
1'ioo i
3? (
44 (
89 (
( 17)
C 9)
( 6)
( 14)
( 0)
I 3)
I 11)
! 14)
! 1?)
! 10)
: 5>
: 12)
: 4)
2)
i)
18)
7)
fl)
16)
------- |