Illinois Bureau of Water Environmental P.O. Box 19276 Protection Agency Springfield, IL 62794-9276 June 2008 IEPA/BOW/08-014 LITTLE WABASH RIVER I WATERSHED TMDL REPORT Printed on Recycled Paper TMDL Development for the Little Wabash River I Watershed, Illinois This file contains the following documents: 1) U.S. EPA Approval letter for Stage Three TMDL Report 2) Stage One Report: Watershed Characterization and Water Quality Analysis 3) Stage Two Report: Data Report 4) Stage Three Report: TMDL Development 5) Implementation Plan Report Final Stage 1 Progress Report Prepared for Illinois Environmental Protection Agency September 2006 Little Wabash Watershed Little Wabash River (C19, C21), Paradise Lake (RCG), Lake Mattoon (RCF), First Salt Creek (CPC-TU-C1), Second Salt Creek (CPD 01, CPD 03, CPD 04), Salt Creek (CP-EF-C2, CP-TU-C3), Lake Sara (RCE), East Branch Green Creek (CSB 07, CSB 08) and Dieterich Creek (COC 10) Limno-Tech, Inc. www.limno.com Little Wabash Watershed September 2006 Final Stage 1 Report Table of Contents First Quarterly Progress Report (April 2006) Second Quarterly Progress Report (May 2006) Third Quarterly Progress Report (June 2006) Fourth Quarterly Progress Report (September 2006) Limno-Tech, Inc. i First Quarterly Progress Report Prepared for Illinois Environmental Protection Agency April 2006 Little Wabash Watershed Little Wabash River (C19, C21), Lake Paradise (RCG), Lake Mattoon (RCF), First Salt Creek (CPC-TU-C1), Second Salt Creek (CPD 01, CPD 03, CPD 04), Salt Creek (CP-EF-C2, CP-TU-C3), Lake Sara (RCE), East Branch Green Creek (CSB 07, CSB 08), Dieterich Creek (COC 10), and Clay City Side Channel Reservoir (RCU) Limno-Tech, Inc. www.limno.com Little Wabash Watershed First Quarterly Progress Report April 2006 Final Stage 1 Report TABLE OF CONTENTS EXECUTIVE SUMMARY .................................................................................................1 Background....................................................................................................................1 Methods..........................................................................................................................1 Results............................................................................................................................1 INTRODUCTION ...............................................................................................................4 TMDL Process...............................................................................................................4 Illinois Assessment and Listing Procedures ..................................................................4 List of Identified Watershed Impairments .....................................................................5 WATERSHED CHARACTERIZATION ...........................................................................8 Methods..........................................................................................................................8 Little Wabash River Watershed Characterization..........................................................8 Lake Mattoon...............................................................................................................22 Little Wabash River (Segment C 19) Watershed Characterization .............................24 Little Wabash (Segment C 21) Watershed Characterization .......................................24 Lake Paradise (Segment RCG) Watershed Characterization.......................................25 Lake Mattoon (Segment RCF) Watershed Characterization .......................................27 First Salt Creek (Segment CPC-TU-C1) Watershed Characterization........................28 Second Salt Creek (Segments CPD 04, CPD 03 and CPD 01) Watershed Characterization ...........................................................................................................29 Salt Creek (Segment CP-TU-C3) Watershed Characterization...................................30 Salt Creek (Segment CP-EF-C2) Watershed Characterization....................................31 Lake Sara (Segment RCE) Watershed Characterization .............................................32 East Branch Green Creek (Segment CSB 08) Watershed Characterization................33 East Branch Green Creek (Segment CSB 07) Watershed Characterization................34 Dieterich Creek (Segment COC 10) Watershed Characterization...............................34 Clay City Side Channel Reservoir (Segment RCU) Watershed Characterization.......35 DATABASE DEVELOPMENT AND DATA ANALYSIS .............................................35 Data Sources and Methods...........................................................................................35 CONFIRMATION OF CAUSES AND SOURCES OF IMPAIRMENT .........................36 Little Wabash (Segment C 19).....................................................................................44 Little Wabash (Segment C 21).....................................................................................48 Lake Paradise (Segment RCG) ....................................................................................49 Lake Mattoon (Segment RCF).....................................................................................51 First Salt Creek (Segment CPC-TU-C1)......................................................................53 Second Salt Creek (Segment CPD 04).........................................................................54 Second Salt Creek (Segment CPD 03).........................................................................54 Second Salt Creek (Segment CPD 01).........................................................................56 Limno-Tech, Inc. Page i Little Wabash Watershed First Quarterly Progress Report April 2006 Final Stage 1 Report Salt Creek (Segment CP-TU-C3).................................................................................56 Salt Creek (Segment CP-EF-C2) .................................................................................57 Lake Sara (Segment RCE)...........................................................................................57 East Branch Green Creek (Segment CSB 08)..............................................................59 East Branch Green Creek (Segment CSB 07)..............................................................59 Dieterich Creek (Segment COC 10) ............................................................................60 Clay City Side Channel Reservoir (Segment RCU) ....................................................61 CONCLUSIONS................................................................................................................62 NEXT STEPS ....................................................................................................................64 REFERENCES ..................................................................................................................64 APPENDIX A. DATA SOURCES AND LOCAL CONTACTS......................................67 APPENDIX B. PHOTOGRAPHS.....................................................................................71 List of Tables Table 1. Impaired Waterbodies in the Little Wabash River Watershed ............................ 6 Table 2. Watershed soils (Source: STATSGO) .............................................................. 14 Table 3. Land Cover in Little Wabash River Watershed.................................................. 17 Table 4. Percent of Fields, by Crop, with Indicated Tillage Practice1.............................. 19 Table 5. 2002 Animal Statistics by County for the Little Wabash River Watershed ....... 19 Table 6. Population Summary.......................................................................................... 21 Table 7. NPDES Discharges and Parameters ................................................................... 23 Table 8. Land Cover in Segment C 21 Little Wabash River Subwatershed..................... 25 Table 9. Land Cover in Segment RCG Lake Paradise Subwatershed .............................. 26 Table 10. Estimated Nonpoint Phosphorus Loading Rates1 ............................................ 27 Table 11. Land Cover in Segment RCF, Lake Mattoon Subwatershed........................... 28 Table 12. Land Cover in Segment CPC-TU-C1 First Salt Creek Subwatershed.............. 29 Table 13. Land Cover in the Second Salt Creek Subwatershed (Segments CPD 04, CPD 03 and CPD 01)......................................................................................................... 30 Table 14. Land Cover in Segment CP-TU-C3 Salt Creek Subwatershed......................... 31 Table 15. Land Cover in Segment CP-EF-C2 Salt Creek Subwatershed ......................... 32 Table 16. Land Cover in Segment RCE Lake Sara Subwatershed................................... 33 Table 17. Land Cover in Segment CSB 08 East Branch Green Creek Subwatershed...... 33 Table 18. Land Cover in Segment CSB 07 East Branch Green Creek Subwatershed..... 34 Table 19. Land Cover in Segment COC 10 Dieterich Creek Subwatershed ................... 35 Table 20. Water Quality Data Summary for the Little Wabash Watershed .................... 37 Table 21. Water Quality Standards and Number of Exceedances.................................... 40 Table 22. Waterbody Impairment Causes and Sources (from IEPA, 2006) for the Little Wabash River Watershed.......................................................................................... 42 Table 23. Other Potential Sources