Bear Branch Watershed Management Plan City of Murfreesboro, Rutherford County, Tennessee May 2013 U.S. Army Corps of Engineers Nashville District Table of Contents Executive Summary ..........................................................................................................................4 1.a Introduction ...............................................................................................................................5 1.b Watershed Partnerships .............................................................................................................7 1.c Visual Stream Assessment – August-September 2012 .................................................................7 2. Bear Branch Watershed Characterization ...................................................................................8 2.a Wetlands ....................................................................................................................................8 2.b Gain/Losing Stream Reaches .....................................................................................................9 2. c Water Quality .................................................................................................................................... 10 2.d Low-Flow and Flood Statistics .......................................................................................................... 11 2.e. Biological and Chemical Sampling .................................................................................................. 12 2.f. Biological Monitoring Considerations ............................................................................................. 12 3. Causes of Impairment ................................................................................................................ 15 3a. Riparian Habitat Loss ....................................................................................................................... 15 3.c Dissolved Oxygen Levels .................................................................................................................... 18 3.d Nutrient Levels ................................................................................................................................... 19 4. Bear and Dry Branches Stream Segments – Site Assessments .................................................... 20 4.a Macedonia Drive to East Northfield Boulevard .............................................................................. 20 Existing Conditions ................................................................................................................. 20 Proposed Actions ..................................................................................................................... 21 4.b East Northfield Boulevard to Dejarnette Lane ............................................................................... 21 Existing Conditions ................................................................................................................. 21 Proposed Actions ..................................................................................................................... 22 4.c Dejarnette Lane to Osborne Lane .................................................................................................... 23 Existing Conditions ................................................................................................................. 23 Proposed Actions ..................................................................................................................... 23 4.d Osborne Lane to Compton Road ...................................................................................................... 24 Existing Conditions ................................................................................................................. 24 Proposed Actions ..................................................................................................................... 24 4.e Compton Road to East Fork Stones River Confluence ................................................................... 25 Existing Conditions ................................................................................................................. 25 Proposed Actions ..................................................................................................................... 25 1 4.f Dry Branch .......................................................................................................................................... 26 Existing Conditions ................................................................................................................. 26 Proposed Actions ..................................................................................................................... 26 5. STEPL Model – Spreadsheet Tool for Estimating Pollutant Load ............................................. 27 6. Recommendations for Bear and Dry Branches........................................................................... 30 6.a Water Quality Sampling Location.................................................................................................... 30 6.b Water Quality Protection Areas ....................................................................................................... 30 6.c Streambank Stabilization through Bioengineering ......................................................................... 31 6.e Channel reconstruction (stream meander restoration) .................................................................. 32 6.f Stream Corridor Measures: Riparian Forest Buffer ...................................................................... 33 6.g Trash/Debris Removal ....................................................................................................................... 33 6.h Stream Corridor Measures: Livestock Exclusion/Management ................................................... 34 6.i Additional resources for watershed restoration project assistance ............................................... 34 7. Conclusions and Recommendations .................................................................................................... 35 List of Figures Figure 1 - Bear Branch - Dry Branch Watershed. Photo courtesy Rutherford County GIS Department ...6 Figure 2- Stones River Watershed, Bear Branch Subwatershed HUC 05130203015 Coutesy of Stones River Watershed Association .................................................................... Error! Bookmark not defined. Figure 3 - Bear Branch Watershed, informal wetland assessment locations .........................................9 Figure 4 - Bear Branch - stream gaining and losing reaches ................................................................ 10 Figure 5 - Turbidity in Bear Branch upper reach Figure 6 - Blackfoot quillwort (Isoetes melanopoda) 11 Figure 7 - Macroinvertebrate sampling locations and collection agency ............................................. 13 Figure 8 - MWSD 2011 Visual Stream Assessment noting riparian loss ............................................... 16 Figure 9 - Bear Branch at Compton Road (left 1966, right 2011)- ....................................................... 16 Figure 10 - Bear Branch at Compton Road - note the downstream channel is filled with sediment ...... 17 Figure 11 - MWSD 2011 Visual Stream Assessment noting sediment sources ..................................... 18 Figure 12 - Bear Branch Stream Segments ......................................................................................... 20 Figure 13 - Debris/sedimentation above East Northfield Blvd, riparian alteration and privet .............. 21 Figure 14 - Bear Branch felled trees and debris, and erosion along unprotected riparian area ............ 22 Figure 15 - Bear Branch above Dejarnette Lane, Bear Branch looking upstream above low-head dam 23 Figure 16- Dry streambed below sink near Osborne Lane, wetland site below major spring site ......... 24 Figure 17 - Debris dam above Osborne Lane, concrete bank stabilization ........................................... 24 Figure 18 - livestock access below Compton Road, Lufkin spring ........................................................ 25 Figure 19 - Access road across Bear Branch below Ayers spring, Dry Branch wetland site ................... 26 Figure 20 - Bear Branch near East Fork Stones River confluence......................................................... 27 2 Figure 21 - Bioengineering for stream stabilization project ................................................................ 31 Figure 22 - Stream meander restoration, from "Stream Corridor Restoration Handbook" and Healthy riparian forest buffer ....................................................................................................................... 33 List of Tables Table 1 - USFWS, NWI Wetlands within Bear Branch Watershed .........................................................8 Table 2 - Visual Stream Assessment, Informal Wetland Assessment .......... Error! Bookmark not defined. Table 3 - Gaining Stream Reaches on Bear Branch* .............................................................................9 Table 4 - Low Flow and Flood Statistics for Bear Branch .................................................................... 12 Table 5 – Biometric Scoring for Family Level Bioregion 7li* ................................................................ 12 Table 6 - Biometric