Status and Trends of Water Quality and Benthic Habitats in the Little Manatee River

1. Status and Trends of Water Quality and Benthic Habitats in the Little Manatee River Environmental Resources Management (ERM) Division Environmental Protection Commission of Hillsborough County 3629 Queen Palm Dr. Tampa, FL 33619-1309

2. EPCHC Data Sources Available • Water Quality Data • Monthly monitoring at fixed stations (long-term surveillance network) since the early-1970’s. Includes large number of chemical and physical parameters • Hillsborough Independent Monitoring Program (HIMP), monitoring since 1999. Focused on physical parameters (salinity, DO, pH, temperature). Combination of fixed stations and 72- hour sensor deployments at randomly-selected locations • Benthic Data • Bay-wide benthic and sediment monitoring since mid-1990’s, during fall “index period” • HIMP monitoring (focused on tidal reaches of Hillsborough, Palm Alafia, and Little Manatee rivers) since 1999

3. Available at: http://www.epchc.org/himp.htm

4. TIDAL FRESHWATER EPCHC long-term surface water monitoring network

5. HIMP Monitoring Locations (Tidal) Benthic Monitoring Stations HIMP Water Quality Monitoring Stations

6. Other Information Sources • SWFWMD land use mapping program (detailed land use maps, updated on 5-year cycle) • U.S. Geological Survey stream gaging program (long-term trends in river flow) • U.S. EPA and FDEP TMDL programs (identify and restore water quality in “impaired” water bodies not currently meeting federal/state water quality standards)

7. Land Use (1999) % of Watershed Altered 47.4 % Agriculture 7.2 % Urbanized 5.7 % Mining

8. Rainfall / River Flow Trends

9. 20-Year Water Quality Trends& Recent Conditions

10. Water Quality ComparisonsTidal River Stations(based on 1984 – 2003 EPCHC monitoring data)

11. Recent Bottom Dissolved Oxygen Conditions (HIMP Data) - Diurnal

12. Recent Bottom Dissolved Oxygen Conditions (HIMP Data) - Daily

13. Dissolved Oxygen Conditions Relative to Other Tidal Rivers

14. Impaired Waters, LMR and vicinity Lower LMR & South Fork of LMR Impaired for DO, Coliforms, & Nutrients TMDLs due in 2008

15. Tampa Bay WatershedImpaired Waters

16. Little Manatee River Benthic Habitats • More coarse-grained (sand) sediments and less silt/clay than the other tidal rivers

17. Comparison of Benthic Species Diversity and Abundance to Other Tidal Rivers

18. Summary – LMR Water Quantity and Quality • No trends in rainfall or annual river flow, but dry-season flow in the LMR has shown an increasing trend since 1940 (SWFWMD studies suggest agricultural irrigation as the cause) • Over the past 20 years, nutrient and chlorophyll levels have improved (declined) at EPC monitoring stations on the LMR • Two LMR segments currently considered “impaired” (for coliform bacteria, nutrients and DO). TMDLs due in 2008 • Relative to the other tidal rivers in Hillsborough County, the LMR appears to have the best water quality

19. Summary – Benthic habitats and organisms • Sandy sediments are the predominant habitats in the tidal portion of the LMR. Higher silt+clay levels are present in the other rivers • Relative to the other tidal rivers in Hillsborough County, benthic species richness and abundance are generally higher in the LMR

20. Future Directions – Watershed Management • EPC is working with several partners (Hillsborough County, City of Tampa, SWFWMD, TBEP, FDEP) to develop a county-wide, multi-stakeholder watershed management program • A primary purpose would be to restore and protect the County’s surface (and ground) water resources, to support future environmental and economic needs • Would help the County comply with Federal and State water quality protection and restoration (MS4 and TMDL) requirements • Will require significant co-ordination among programs in several agencies and departments • Planning, zoning and growth management issues are critical elements of the watershed management process