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              Illinois Environmental Protection Agency Charleston Side Channel Reservoir TMDL
APPENDIX
A Water Quality Data
B SWAT 2000 Modeling of the Upper Embarras River Watershed
C BATHTUB Modeling of the Charleston Side Channel Reservoir
D Charleston Side Channel Reservoir TMDL Draft Project Implementation Plan
E Charleston Side Channel Reservoir TMDL Responsiveness Summary
FIGURES
Figure 1. Upper Embarras River Watershed and the Charleston Side Channel Reservoir. ..........................3
Figure 2. Charleston Side Channel Reservoir and Lake Charleston. ............................................................5
Figure 3. Land Use in the Charleston Side Channel Reservoir Direct Drainage Area. ................................7
Figure 4. Land Use in the Upper Embarras River Watershed.......................................................................9
Figure 5. Annual Precipitation in Charleston, Illinois (1990–2000)...........................................................11
Figure 6. Location of Water Quality Monitoring Stations..........................................................................13
Figure 7. 1998 Total Phosphorus Observations. .........................................................................................16
Figure 8. Average Total Phosphorus Concentrations, 1983–2001. ............................................................17
Figure 9. 1998 Observed Chlorophyll a Concentrations. ...........................................................................19
Figure 10. Annual Mean Chlorophyll a Concentrations, 1983–2001.........................................................19
Figure 11. Upper Embarras River Watershed Modeled Using SWAT2000, Divided into Subwatersheds.23
Figure 12. Phosphorus Loads to the Charleston Side Channel Reservoir...................................................27
TABLES
Table 1. Charleston Side Channel Reservoir Section 303(d) Listing Information. ......................................2
Table 2. Land Use Distribution in the Area Directly Draining to the Charleston Side Channel Reservoir..6
Table 3. Land Use in the Upper Embarras River Watershed........................................................................8
Table 4. Population for the Five Counties That Overlap the Upper Embarras River Watershed. ..............10
Table 5. Pumping Records from 1981 to 2000 (million gallons) (City of Charleston, 2002). ...................12
Table 6. TN:TP Ratios at Station RBC-1....................................................................................................15
Table 7. Average Monthly Concentrations of Dissolved Phosphorus and TP at RBC-1 for the Period 1983
to 2001 (IEPA data). ............................................................................................................................18
Table 8. Average Values of the TSI for the Charleston Side Channel Reservoir. ......................................20
Table 9. Phosphorus Concentration in Lake Charleston (Sampling Done by City of Charleston in 2000).1,2
............................................................................................................................................................21
Table 10. NPDES Facilities in the Embarras River Watershed Upstream of the Charleston Side Channel
Reservoir and Their Estimated Annual Discharge of Phosphorus (March 1998 to March 2002). ......24
Table 11. Current Total Phosphorus Loads to the Charleston Side Channel Reservoir. ............................27
Table 12. Results of BATHTUB Modeling (Calibration Period). ..............................................................29
Table 13. Results of BATHTUB Modeling (Validation Period). ...............................................................29
Table 14. Predicted Impact of 87 Percent Reduction in Phosphorus Loads. ..............................................30
Table 15. TMDL Summary for Charleston Side Channel Reservoir..........................................................30
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