5664
905R83119
STUDIES OF SEDIMENT, NUTRIENT
AND PESTICIDE LOADING IN SELECTED
LAKE ERIE AND LAKE ONTARIO TRIBUTARIES
Draft Final Report
U. S. EPA Grant No. R005708-01
Part V
Sediment and Nutrient Loading Summary
Submitted to:
Mr. Clifford Risley, Jr.
Project Officer
U. S. Environmental Protection Agency
Region V
536 South Clark Street
Chicago, Illinois 60605
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.',o. Environments! Protection Agency
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CONTENTS
TABLES i
FIGURES ii
INTRODUCTION 1
METHODS 4
Sample Collection 4
Analytical Methods 4
RESULTS AND DISCUSSION 6
Analytical Results 6
Runoff Patterns for the 1982 Water Year 7
Nutrient and Sediment Concentrations 16
Nutrient and Sediment Loading 18
CONCLUSIONS 23
RECOMMENDATIONS 23
REFERENCES 25
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TABLES
Number Page
Station codes, flows, sampling dates and numbers of samples
analyzed for the 1982 water year tributary loading program . 5
Flux weighted and time weighted mean concentrations at the
transport stations for the 1982 water year 17
Nutriattand sediment loads at the transport stations for
the 1982 water year 19
Unit area nutrient and sediment yields at the transport
stations for the 1982 water year 21
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FIGURES
Number Page
1 Locations of the 1982 tributary monitoring stations in the
Lake Erie Basin 2
2 Locations of the 1982 tributary monitoring stations in the
Lake Ontario Basin 3
3 2
3 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Raisin River for the 1982 water year 8
3 2
4 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Maumee River for the 1982 water year 9
3 2
5 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at Honey Creek for the 1982 water year 10
3 2
6 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Sandusky River for the 1982 water year .... 11
3 2
7 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Cuyahoga River for the 1982 water year .... 12
3 2
8 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Genesee River for the 1982 water year 13
3 2
9 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Oswego River for the 1982 water year 14
3 2
10 Unit area flow (m /sec/km ) and total phosphorus concentration
(mg/L) at the Black River for the 1982 water year 15
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INTRODUCTION
Tributaries comprise the major pathway by which many pollutants enter
Lake Erie and Lake Ontario. Accurate tributary loading data are therefore
essential to develop accurate total pollutant loading data for these lakes.
Accurate total loading data are necessary to establish the relationships
between pollutant loadings and resulting water quality and to subsequently
develop and refine target loads which should result in meeting water quality
objectives. Accurate tributary loading data also reflect the effectiveness of
pollution abatement programs within the tributary watersheds..
For the 1982 water year, the Great Lakes National Program Office (GLNPO)
of the U.S. Environmental Protection Agency supported a special tributary
loading study for the major tributaries of Lake Erie and Lake Ontario.
Loading studies were also conducted at the Honey Creek Tillage Demonstration
Watershed in Seneca and Crawford counties, Ohio. The locations of the
tributary loading stations are shown in Figures 1 and 2.
In this part of the final report, loading data for nutrients and
sediments will be presented. Previous parts of the final report have dealt
with pesticide loading (Baker, 1983a), bioavailable phosphorus loading (Baker,
1983b), Monte Carlo analyses of sampling strategies, (Richards, 1983) and
Honey Creek tillage surveys (Krieger, 1983).
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METHODS
Sample Collection
All of the samples were collected at or near the U.S. Geological Survey
stream gaging stations listed in Table 1. At the stations located in Ohio,
automatic samplers (ISCO Model 1680 or equivalent) were used to collect
discrete samples at six hour intervals. During periods of high flow, all
samples were analyzed, whereas, during low flow, one sample per day was
analyzed. Details of our use of automatic samplers for tributary loading
studies have been described elsewhere (Baker, 1983c).
At the Michigan and New York stations local observers were used to
collect grab samples. Samples were refrigerated and shipped to the laboratory
at weekly intervals. The number of samples collected at each station, along
with the inclusive sampling dates, are listed in Table 1.
Analytical Methods
All samples were analyzed for soluble reactive phosphorus (SRP), total
phosphorus (TP), suspended solids (SS), nitrate + nitrite nitrogen (N02.3),
total Kjeldahl nitrogen (TKN), dissolved silica (Si02), chloride (CL), and
conductivity (Cond.). In addition, ammonia analyses were run on weekly
samples for the four Ohio stations. These samples were filtered at the time
of sample collection.
The analytical methods have been described in detail in quality assurance
materials submitted to the Quality Assurance Office, Region V, U.S. EPA. The
following documents contain information on both analytical methods and related
quality control results:
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1. Baker, David B. January 1981. "Quality Assurance Program for Detailed
Tributary Loading Studies in Event Response Rivers." Submitted to James
H. Adams, Chief, Quality Assurance Office, Region V, U.S. EPA.
2. Baker, David B. March 1982. "The Effects of Sample Storage for One Week
Without Preservation on Soluble Reactive Phosphorus Loading
Measurements." Submitted to David Payne, Quality Assurance Office,
Region V, U.S. EPA and Marcella Gewirth, Great Lakes National Program
Office, Region V, U.S. EPA.
3. Baker, David B. June 1982. Quality Assurance Program Update - Responses
to the April 16, 1982 Report by the Region V, EPA Quality Assurance
Office on its On-Site Evaluation of the Water Quality Laboratory of
Heidelberg College, Tiffin, Ohio. Submitted to the Quality Assurance
Office, Region V, U.S. EPA,
RESULTS AND DISCUSSION
Analytical Results
All of the analytical results for the 1982 water year have been placed in
the STORET system using the U.S. Geological Survey station identifications
shown in Table 1. A copy of archive printouts from our laboratory's data
system containing all of the 1982 data is included in the appendix to this
report. The formats for our archive printout have been described previously
(Baker, 1983c). A copy of our archive printout has also been sent directly to
Dr. John Clark of the International Joint Commission (IJC) in Windsor,
Ontario, for use in calculating IJC loading estimates for the 1982 water year.
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Runoff Patterns for the 1982 Water Year
The total discharge for the 1982 water year was higher than the long term
average discharge at all eight of the stations (Table 1). For most of the
streams, highest discharges occurred in March during a snowmelt period. For
the Black River in New York the peak snowmelt runoff occurred in April.
Unusually heavy snow accumulations in southeastern Michigan and northwestern
Ohio resulted in extensive spring flooding of the Raisin and Maumee rivers.
In Figues 3-10, the unit area discharges and the chetnographs of total
phosphorus for the 1982 water year are shown. Runoff patterns for suspended
solids parallel the total phosphorus chetnographs. For the Michigan and New
York streams, the daily discharges were shown for the entire water year even
though the chemical sampling programs encompassed only a portion of the water
year. For the Ohio streams, the cheraographs and hydrographs both extend for
the entire water year. Any gaps in the chemical record, due to sampler
malfunction, are also shown as gaps in the hydrograph records for the Ohio
stations.
The graphs of Figures 3-10 nicely illustrate the differences between
event-response and stable-response rivers. For stable-response streams, such
as the Oswego and Black rivers (Figures 9 and 10), changes in discharge rate
are not accompanied by large changes in phosphorus concentrations. In
event-response rivers, such as the Maumee, Sandusky and Cuyahoga rivers and
Honey Creek (Figures U-7), periods of increased runoff are accompanied by very
large increases in phosphorus concentrations. The Raisin and Genesee rivers
are intermediate in that runoff events in these streams are accompanied by
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smaller increases in nutrient concentrations than are the Ohio streams. As
will be noted subsequently, the unit area phosphorus loads are much higher for
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the graphs of Figures 3-10 that much more frequent sample collection is
necessary to quantify nutrient export from event-response streams than for
stable-response streams. Sampling requirements for the Sandusky River have
been analyzed using Monte Carlo techniques and are discussed in a separate
report (Richards, 1983).
Nutrient and Sediment Concentrations
The flux weighted mean concentration and the time weighted mean
concentration for each parameter at each station are shown in Table 2. These
concentrations are calculated as follows:
Flux wt. cone. - Z
Time wt. cone. r I -
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where c^ = concentration of the i sample
q^ = instantaneous discharge for the i*-*1 sample
t^ = time interval associated with the j.th sample
Both the flux weighted and time weighted concentrations are calculated as
part of the flux summary program used in our data analyses (Baker 1983c).
Substances whose concentrations increase with increasing flow (e.g., TP, SS,
and N02-3 in event-response rivers) have higher flux weighted concentrations
than time weighted concentrations. Printouts from the flux summary programs
for each parameter and station are included in the appendix to this report.
The nutrient and sediment concentrations are much lower in the Black and
Oswego rivers than in the other streams. The Oswego River does have the
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highest chloride concentrations and highest conductivity of any of the rivers
included in the study. The high chloride content in the Oswego river is due,
in part, to the high salt content of Lake Onondaga near Syracuse, New York.
That lake receives wastes from a chlor-alkali manufacturer (Effler, et.al.,
1983). In contrast the Black River has by far the lowest chloride
concentrations and the lowest conductivity of any of these streams. This is
apparently associated with the granitic bedrock within the Black River Basin.
The Ohio tributaries to Lake Erie have the highest soluble reactive
phosphorus and total phosphorus concentrations. For the Maumee and Sandusky
rivers and for Honey Creek, the high phosphorus concentrations are primarily
related to agricultural land use. These three streams also have very high
flux weighted nitrate-nitrite concentrations. The high phosphorus
concentrations in the Cuyahoga River are largely due to point source
phosphorus loading in the watershed (Baker 1983b).
The Genesee and Raisin rivers are intermediate in terms of their nutrient
concentrations. It is noteworthy that the River Raisin, whose watershed has a
higher average gross erosion rate than that of the Sandusky (Logan, et.al.,
1982), has a much lower flux weighted sediment concentration than the Sandusky
River. This illustrates the importance of sediment delivery ratios in
affecting sediment yields for watersheds.
Nutrient and Sediment Loading
The annual loading of nutrient and sediments at the transport stations
are shown in Table 3» For the Lake Erie tributaries the annual loads were
calculated by determining the flux weighted mean concentrations of each
parameter for each month at each station. The flux weighted mean
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concentrations were then multiplied by the final U.S. Geological Survey
monthly discharge values to obtain the monthly loads. The monthly loads were
then summed to obtain the annual load. The computerized work sheets for these
calculations are included in the appendix. This method of calculating annual
loads has been described in detail by Baker (1983c).
For the Lake Ontario tributaries, where fewer data were available,
nutrient loads were calculated by multiplying the flux weighted mean for the
entire sampling period (Table 2) by the total annual discharge (Table 1).
In Table 4 the unit area loads of nutrients and sediments are shown for
each station. In all cases the unit area loads were calculated by dividing
the total load (Table 3) by the total watershed area (Table 1).
The Maumee River contributed the largest loads of nutrients and sediments
to the lower lakes (Table 3). The unit area loads of total phosphorus were,
however, higher in the Cuyahoga and Sandusky rivers than in the Maumee (Table
1). The influence of agricultural runoff is most easily seen in the high unit
area nitrate-nitrite loads of the Maumee and Sandusky rivers and of Honey
Creek.
The role of tributary loading in the overall phosphorus budget for Lake
Erie has been described in connection with the studies of bioavailable
phosphorus loading '(Baker, 1983b). The total phosphorus load at the Raisin,
Maumee, Sandusky, and Cuyahoga stations accounted for 27% of the total
phosphorus loading estimate for the lake from all sources. The procedures for
extrapolating from loading data at the transport stations to total tributary
and land runoff loading data are presented in the bioavailable phosphorus
loading report. The relationship of the 1982 total phosphorus loads to recent
loading trends in the Sandusky Basin is also discussed in that report.
The 1982 loading studies represent the first year of a three year
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program. At the conclusion of the 198M studies, a more comprehensive final
report on tributary loading will be presented.
22
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CONCLUSIONS
The triburary loading program for lakes Erie and Ontario during the 1982
water year has produced a rather comprehensive and consistent data base for
the calculations of tributary loads to these lakes. The unit area nutrient
and sediment loadings from these streams differ greatly from one another and
reflect a combination of differences in both land use and land resources. The
"event response" character of Ohio streams is clearly evident in the data.
At the time of this writing, the IJC has not yet completed its
calculations of tributary loading to the lower lakes for 1982. Information on
the usefulness of this data for pollutant loading calculations by the IJC will
be of interest. Dr. John Clark of the IJC will use the Beale ratio estimator
technique with stratification for calculating loads for the New York streams.
Comparisons of those loads with loads calculated using the overall flux
weighted mean and total annual discharge will be of interest.
RECOMMENDATIONS
Considerable lead time is necessary for the support and development of
tributary loading programs. At the time of data analyses and reporting for
the 1982 programs, 85% of the data for the 1983 program has already been
collected and the proposals outlining the 1984 program have already been
submitted. In less than nine months, proposals for the 1985 program should be
submitted to the EPA. The budget planning process of the EPA for the support
of tributary loading programs must, of necessity, work even further in
advance.
23
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U.S. Environmental Protection Agency
Region V, Library
230 South Dearborn Street
Chicago, Illinois 60604
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Several new components have been added to the tributary loading programs
in recent years. Attempts to measure bioavailable phosphorus loading have
been incorporated into the programs. Loading studies of currently-used
pesticides have been added to the Lake Erie programs. I believe that prior to
setting forth the 1985 water year programs, an evaluation and review of the
Great Lakes tributary loading programs is in order. Laboratories involved in
the program could share information on sampling and analytical techniques.
Data users could comment on the adequacy of existing data and other data
needs. Perhaps the Great Lakes National Program Office could convene some
sort of session wherein issues dealing with tributary loading studies could be
discussed and addressed.
24
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