U.S. ENVIRONMENTAL PROTECTION AGENCY
NATIONAL EUTROPHICATION SURVEY
WORKING PAPER SERIES
REPORT
ON
COCODRIE U\KE
GONCORDIA PARISH
LOUISIANA
EPA REGION VI
WORKING PAPER No, 534
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY - CORVALLIS, OREGON
and
ENVIRONMENTAL MONITORING & SUPPORT LABORATORY - LAS VEGAS, NEVADA
•&G.P.O. 699-440
-------
REPORT
ON
COCODRIE LAKE
CONCORDIA PARISH
LOUISIAMA
EPA REGION VI
WORKING PAPER No, 534
WITH THE COOPERATION OF THE
LOUISIANA WILD LIFE AND FISHERIES COMMISSION
AND THE
LOUISIANA NATIONAL GUARD
MARCH, 1977
-------
REPORT ON COCODRIE LAKE
CONCORDIA 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. 534
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
March 1977
-------
CONTENTS
Page
Foreword i i
List of Louisiana Study Lakes iv
Lake and Drainage Area Map v
Sections
I. Introduction 1
II. Conclusions 1
III. Lake Characteristics 2
IV. Lake Water Quality Summary 3
V. Literature Reviewed 8
VI. Appendices 9
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11
FOREWORD
The National Eutrophication Survey was Initiated in 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
planning [§303(e)], water quality criteria/standards review
[§303(c)L clean lakes [§314(a,b)], and water quality monitoring
[§106 and §305(b)] activities mandated by the Federal Water
Pollution Control Act Amendments of 1972.
-------
iii
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 augment plans implementation by the states.
ACKNOWLEDGMENTS
The staff of the National Eutrophicatlon Survey (Office of
Research and Development, U.S. Environmental Protection Agency)
expresses sincere appreciation to the Louisiana Wild 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 R. Still, Biologist; Louis Johnson, Biologist; Lee Cau-
barreaux, Biologist; Darrell Reed, Engineer; Dempsey A.lford,
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'Nell 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 Vernbn
Lake Verret
PARISH
Vernon
Bienville, Webster
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
-------
Bill John Bayou
Map Location
COCODRIE LAKE
Tributary Sampling Site
X Lake Sampling Site
-------
REPORT ON COCODRIE LAKE, LOUISIANA
STORE! NO. 2207
I. INTRODUCTION
Cocodrie Lake was included in the National Eutrophication
Survey (NES) as a water body of interest to the Louisiana Stream
Control Commission and the Louisiana Wild Life and Fisheries Com-
mission. Tributaries and nutrient sources were not sampled, and
this report relates only to the data obtained from lake sampling.
II. CONCLUSIONS
A. Trophic Condition:*
Survey data indicate that Cocodrie Lake is eutrophic,
i.e., nutrient rich and highly productive. Whether such
nutrient enrichment is to be considered beneficial or dele-
terious is determined by its actual or potential impact upon
designated beneficial water uses of each lake.
Of the 19 Louisiana lakes sampled in 1974, only 5 had
higher median total phosphorus levels, 3 had higher median
orthophosphorus values, and none had greater median inorganic
nitrogen levels than Cocodrie Lake. Chlorophyll a_ levels were
high, ranging from 4.6 yg/1 in March to 65.8 pg/1 in May,
with a mean of 35.3 yg/1. Secchi disc visibility was very
low, and potential for primary production as measured by algal
assay control yield was high.
*See Appendix C.
-------
Survey limnologists did not report any nuisance conditions
in this small, turbid lake.
B. Rate-Limitng Nutrient:
Algal assay results indicate that Cocodrie Lake was growth
limited by available nitrogen levels at the time of spring sampling.
Mean inorganic nitrogen to orthophosphorus ratios (N/P) for the lake
were 12/1 during March, suggesting nitrogen limitation, and 23/il in
May, indicating phosphorus limitation at that time.
li-I. LAKE CHARACTERISTICS
A. Lake Morphometry:*
2
A. Surface area: 3.99 km .
B. Mean depth: 4.9 meters.
C. Maximum depth: 6.4 meters.
D. Volume: 19.551 x 106 m3.
B. Precipitation:
A. Year of sampling: 165.8 cm.
B. Mean annual: 151.6 cm.
*Provided by the State of Louisiana.
-------
IV. LAKE WATER QUALITY SUMMARY
Cocodrie Lake was sampled two 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 two 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 3.0 meters at Station 01 and 4.3
meters at Station 02. 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 IV-A for waters at the surface and at the
maximum depth for each site. Results of the phytoplankton
counts and chlorophyll ^determinations are included in IV-'B.
Results of the limiting nutrient study are presented in IV-C.
-------
STO-£T cos. t >?•• f
T.CAL AN!.) CntMlCAI. CHAUACTt^ IST ICS
TE'-'-ii-'t TJ-C. tce.f
ri.-l.-. !>< OErTn
DISSOLVED OXYL-E'i
O.-l.S K UiL^TH
0.-1.5
MA*
0.-1.5 V ')t*-Th
MAX OEPTH«o
TOTAL ALKALINITY (M(i/L)
0.-1.5 M uEPTn
MA* OEPTri»*
TOTAL P (Nifi/L)
0.-1.5 N; 'ItV-TH
DISSOLVED O^THO
0.-1.5
MAX
H02+N03
O.-l.S M Ofc.
(MG/L)
O.-l.S
MAX (lE
.L N (M'5/L)
.-l .S M OEPTH
( J/lV/74 ]
2.
2
4
2
2
l
2
2
L)
2
2
\
?
1H.V-
18. P-
7.3-
7.4-
127.-
7.1-
7.1-
50.-
0.0*8-0
0.033-0
0.033-0
0.3^0-0
0.400-0
0.060-0
0.060-0
0.500-0
0.500-0
1 V . 0 •
7.4
7.6
13V.
13*.
7.2
7.2
5fl!
.115
.112
.045
.042
.440
,06u
.070
.600
.600
1 °. . •>
7.3
7.5
133.
13?.
7.2
7.1
54.
0.104
0. 105
0.03*
0.037
0.410
0.420
0.065
li . 6 0 0
u.550
i
I
1
3
\
3
0
3
0
3
0
3
0
3
0
3
0
3
0
3
0
3
""ETtxS) N« r*ANGE MEOIAN
.0-
.'0-
.5-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
.0-
4*,3
1.5
4.3
1.5
4.3
1.5
4.3
1.5
4.3
1.5
4.3
1.5
4.3
1.5
4.3
1.5
4.3
4.3
4 27.6-
c 27.4-
2 7.4-
2 f.4-
2 160.-
4 8.3-
c 8.2-
4 55.-
2 56.-
4 0.051-0
2 0.066-0
4 0.006-0
2 O.OOf-0
4 0.110-0
2 0.120-0
4 0.040-0
?. 0.110-0
^ O.nOO-l
?. 0 . 9 0 0 - 0
26.0
6.8
8.8
160.
160.
8.7
8.6
57.
57.
.084
.086
.018
.01V
.230
.230
.120
.120
.000
28.0
27.7
8.1
8.1
15V.
160.
8.5
8.4
56.
57.
0.067
0.076
0.011
0.013
0.175
0.105
0.115
0.950
o.eoo
"AX
OEPT-
-------
B. Biological Characteristics:
1. Phytoplankton -
Sampling
Date
03/19/74
05/29/74
Dominant
Genera
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
Flagellates
Merismopedia
Nitzchia
Mi crocy sti s
Ankistrodesmus
Other genera
Total
Cyclotella
Stephanodiscus
Melosira
Flagellates
Pennate diatom
Other genera
Algal
Units
per ml
2,134
459
459
306
268
422
4,057
6,595
2,721
2,593
1,729
1,121
2,402
Total
2. Chlorophyll a_ -
17,161
Sampling
Date
03/19/74
05/29/74
Station
Number
01
02
01
02
Chlorophyll
(uq/D
11.8
4.6
65.8
59.0
a_
-------
C. Limiting Nutrient Study:
1. Autoclaved, filtered, and nutrient spiked -
Ortho P Inorganic N Maximum Yield
Spike (mg/1) Cone, (mg/1) Cone, (nig/1) (mg/1-dry wt.)
Control 0.040 0.393 7.1
0.05 P 0.090 0.393 7.6
0.05 P + 1.0 N 0.090 1.393 17.3
1.00 N 0.040 1.393 11.0
2. Discussion -
The control yield of the assay alga, Selenastrum
capricornutum, indicates that the potential for primary pro-
duction in Cocodrie Lake was high at the time of spring as-
say sample collection. Growth response with the addition of
nitrogen as well as the lack of significant response to the
addition of phosphorus indicated nitrogen limitation. Maxi-
mum growth yield was achieved with the simultaneous addition of
both phosphorus and nitrogen.
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 chemi-
cal changes are likely to alter the assay control yield as
well as modifying the N/P ratio.
The autumn algal assay results have not been included
as these substantial changes in nutrient levels have removed
their information value.
-------
The mean N/P ratio for Cocodrie Lake was 12/1 during March samp-
ling, suggesting nitrogen limitation. The N/P for May sampling was
23/1, indicating phosphorus limitation at that time.
-------
V. LITERATURE REVIEWED
U.S. Environmental Protection Agency. 1975. National
Eutrophication Survey Methods 1973-1976. Working Paper No. 175.
National Environmental Research Center, Las Vegas, Nevada, and
Pacific Northwest Environmental Research Laboratory, Corvallis,
Oregon.
-------
VI. APPENDICES
APPENDIX A
CONVERSION FACTORS
-------
CONVERSION FACTORS
Hectares x 2.471 = acres
Kilometers x 0.6214 = miles
Meters x 3.281 = feet
Cubic meters x 8.107 x 10 = 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
PHYSICAL AND CHEMICAL DATA
-------
STu-tT HtTmtVAL OATE 7b/13/H
MATL EUTSOPHICATION SURVEY
EPA-LAS
?20701
31 30 £0.0 Ovl n3
COCODWIE LAKE
32 LOUISIANA
40.0
DATE
FiiQ1"'1
TO
74/03/19
74/05/29
DATE
FROM
TO
74/03/19
74/05/39
TIME DEPTf
OF
DAY FEET
14 00 0000
14 00 Ou05
14 00 0010
15 30 0000
15 30 000^
15 30 0010
TIME DEPTH
OF
DAY FEET
14 00 0000
14 00 0005
14 00 0010
15 30 0000
15 30 0005
15 30 0010
00010
*ATEft
TEMP
CENT
1H.9
18.9
18.8
38.3
38.3
38.0
00665
PHOS-TOT
MG/L P
0.096
0.094
0.098
0.051
0.059
0.066
00300
DO
MG/L
7.4
7.6
8.8
8.8
33217
CHLRPHYL
A
U6/L
11.8
6b.8
00077
TriAl-J.SP
SECCrtl
INCHES
20
24
00031
INCDT LT
PENNING
PERCENT
000 v-
CfMUUCTVY
FIELD
MICMOMHO
139
138
136
143
159
160
11EPALES 21112!!2t>
TOT. *JtL
N
*G/L
O.bOO
0.600
0.600
1.000
O.nOO
O.HOO
TM
006TO
N02S.N03
N-TOTAL
fG/L
0.380
0.390
0.400
0.150
0.110
0.120
00o71
PHOS-DIS
O^TiO
MG/L P
0.036
0.033
0.033
n.ooa
0.006
0.007
-------
T- 75/12/11
NATL
EPA-LAS VEGAS
2207P2
31 ?9 55,0 091 »? 20.0
COCODKlE LtKE
32 LOUISIANA
DATE
FROM
TO
74/03/19
74/05/39
DATE
FROM
TO
74/03/19
74/05/39
TI*E OEPT-
OF
DAY FEET
14 30 0000
14 30 0005
14 30 0014
15 15 0000
15 15 0005
15 15 0010
TIME OEPTH
OF
DAY FEET
14 30 0000
14 30 0005
14 30 0014
15 15 0000
15 15 0003
15 15 0005
15 IS 0010
OCOlO
• 4Tc-»
Tt«P
CENT
1^.0
19lo
19.0
27.8
27.6
27.4
00665
PHOS-TOT
MG/L P
0.115
0.113
0.112
0.076
0.044
0.086
00300
00
MG/L
7.3
7.4
7.4
7.4
32217
CHLRPHYL
A
UG/L
4.6
5SP.O
00077 0009
0062D
TOT KJtL
N
MG/L
0.600
0.500
0.500
1.000
0.900
O.MOO
TM
00630
N02&N03
N-TOT»L
-G/L
0.430
0.450
0.440
0.200
0.230
O.P30
00671
PHOS-OIS
O^TnO
MG/L P
0.043
0.045
0.04?
0.01P
0.015
0.019
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APPENDIX C
PARAMETRIC RANKINGS OF LAKES
SAMPLED BY NES IN 1974
STATE OF LOUISIANA
-------
LAKE OATA TO =• USED ;•
LAKE
CODE LAKE NA«E
2201 ANACOCO L^-i
2302 BPUIN LAKE
2203 LAKE filSTI'-.Ei,..
2204 BLACK SAY-..,.
2205 B'JNDICK L^KE
2207 COCODRIE Li
-------
PERCENT OF LAKES »ITH HIGHER VALUES
LAKE
CODE LAKE NAME
'"'F LAKES KITH MIGHEH VALUES)
22
92
61
50
7?
11
2*
81
44
S6
79
33
92
17
0
6
100
39
22
67
( 16)
( 11)
( 9)
( 13)
( 2)
( 5)
( 15)
( 8)
( 10)
( 14)
( 6)
( 16)
( 3)
( 0)
( 1)
( 18)
( 7)
( 4)
( 12)
MEDIAN
INCHG N
63 (
11 (
53 (
72 (
33 (
0 (
58 (
83 (
83 (
58 (
39 (
29 (
6 (
17 (
58 (
44 (
22 (
100 (
94 (
14)
2)
9)
13)
6)
0)
Si)
14)
14)
9)
7)
5)
1)
3)
9)
8)
4)
18)
17)
500-
MFAN SEC
67
83
61
78
33
11
94
39
28
56
89
50
0
22
6
100
72
17
44
( 12)
( 15)
( 11)
( 14)
( 6)
( 2)
( 17)
t 7)
( 5)
( 10)
( 16)
< 9)
( 0)
( 4)
( 1)
( 18)
( 13)
( 3)
( 8)
MEAN
CHLORA
89
61
72
56
44
11
83
22
6
94
28
39
67
33
0
100
78
17
50
( 16)
( 11)
( 13)
( 10)
( 8)
t 2)
( 15)
( 4)
< 1)
( 17)
( 5)
( 7)
( 12)
( 6)
( 0)
( 18)
( 14)
t 3)
( 9)
15-
MIN 00
83
0
42
bO
78
100
33
14
72
42
6
14
94
22
56
28
67
61
89
( 15)
( 0)
< 7)
( 9)
( 14)
( 18)
( 6)
( 2)
( 13)
( 7)
( 1)
( 2)
( 17)
( 4)
( 10)
( 5)
( 12)
( 11)
( 16)
MEDIAN
DISS OBTHO
9« (
50 (
33 (
81 (
0 (
17 (
61 (
81 (
69 (
56 (
28 (
69 (
22 (
11 (
6 (
100 (
39 <
44 (
89 (
17)
9)
M
14)
0)
3)
.">
14)
1?)
10)
5)
12)
4)
?)
1)
1ft)
7)
ft)
16)
------- |