The Wisconsin River TMDL: Linking Monitoring and Modeling

1. The Wisconsin River TMDL: Linking Monitoring and Modeling Ann Hirekatur, Pat Oldenburg, & Adam Freihoefer March 7, 2013 Wisconsin River TMDL Project Team WDNR Bureau of Water Quality

2. The Wisconsin River Basin (WRB)

3. The WRB – A managed system http://www.lakenokomiscc.org

4. Dells of the Eau Claire Water Quality Concerns within the WRB Fish Kills in Big Eau Pleine Reservoir Petenwell and Castle Rock Flowages Runoff in the Baraboo

5. Pollutant Sources within the WRB Non-MS4 Stormwater Construction Rill, Gully, & Bank Erosion Nonpoint Sources Agricultural Runoff Barnyards Point Sources Industrial Waste Municipal Waste

6. WRB Total Maximum Daily Load (TMDL) Each subwatershed is assessed for: • Background Load • Naturally occurring from • wetlands, forests • Load Allocation • Runoff from the landscape • Waste Load Allocation • Municipal Wastewater • Industrial Wastewater • Stormwater (MS4s) TMDL Load Allocation Waste Load Allocation Margin of Safety + +

7. Components of the WRB TMDL Implementation Draft TMDL Final TMDL EPA Approval Internal Review Public Comment • Monitoring • Flow • Chemistry • In-lake • Conceptualization • Data Analysis • Windshield Surveys • Modeling • Watershed • Point Sources • Fate and Transport • Reservoirs • Allocations • Load • Wasteload • Margin of Safety • Civic Engagement • Public Outreach/Communications

8. Past Activities in the WRB 2010 WNDR receives Section 22 Planning Assistance from USACE 2009 – 2013 Wisconsin River TMDL Monitoring 2001 WDNR/USACE develop joint TMDL monitoring proposal for $1.5 million. Proposal not funded 2008 First Pontoons and Politics at Petenwell Castle Rock 2009 State legislature appropriates $750,000 ($150,000/yr. for 5 years) for monitoring upstream of Castle Rock 1996 Petenwell Castle Rock Comprehensive Management Plan 2004 WDNR proposal to USEPA for river water quality monitoring. Proposal not funded Wisconsin River TMDL

9. The WRB Monitoring - Modeling Relationship Monitoring Conceptualization

10. WRB Monitoring Approach Critical Idea Design a monitoring plan that provides an understanding of the system and supports the modeling of the watershed & reservoirs

11. WRB Monitoring Approach Tributary Watershed Loads 19 stations with daily discharge & bi-monthly water quality = ungauged tributary area

12. WRB Monitoring Approach Tributary Watershed Loads 19 stations with daily discharge & bi-monthly water quality Phosphorus Evaluation Sites 98stations with monthly P samples between May – October 2012 with 31 sites proposed for re-sample in 2013

13. WRB Monitoring Approach Tributary Watershed Loads 19 stations with daily discharge & bi-monthly water quality Phosphorus Evaluation Sites 98stations with monthly P samples between May – October 2012 with 31 sites proposed for re-sample in 2013 Main stem Loads 13 stations with daily discharge & bi-monthly water quality

14. WRB Monitoring Approach Tributary Watershed Loads 19 stations with daily discharge & bi-monthly water quality Phosphorus Evaluation Sites 98stations with monthly P samples between May – October 2012 with 31 sites proposed for re-sample in 2013 Main stem Loads 13 stations with daily discharge & bi-monthly water quality Reservoirs 5 major reservoirs Big Eau Pleine, Lake Dubay, Petenwell, Castle Rock , & Lake Wisconsin

15. WRB Model Approach – Watershed • Simulates conditions on landscape each day based on climate data • Input data intensive • Output information is provided for each subwatershed defined (TMDL reach) • Outputs include crop yields, discharge, sediment, & water chemistry

16. WRB Model Approach – Watershed Model Input Climate Precipitation, Temp, etc. Model Output Land Management Agriculture, Urban Land Cover WATERSHED MODEL Watershed Model Calibrated Outputs 2009 – 2013 Conditions Soils Type and Attributes Topography Slope Model Calibration Required Hydrography Flow accumulation, Internal drainage, groundwater Point Sources

17. WRB Model Approach – Reservoir Petenwell Bathymetry (Developed by USACE)

18. WRB Model Approach – Reservoir Model Input Model Output RESERVOIRMODEL Reservoir Model Outputs Watershed Model Calibrated Outputs Model Inputs Model Calibration Required

19. WRB Model Approach – Model Calibration Input Parameter Controls • Calibration is process of matching the simulation to measured data • Modeler adjusts model parameters to allow for better fit

20. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs Assess the daily flow and TP concentrations Use regression model to estimate monthly TP load, referred to as “measured load” Compare the watershed model “simulated load” to the “measured load”. Adjust the model to reflect measured conditions, a process referred to as model calibration Dill Creek - Big Eau Pleine River

21. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs

22. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs

23. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs EXAMPLE

24. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs

25. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs • Same approach as the tributary loads (daily discharge, bi-monthly water quality)

26. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs • Same approach as the tributary loads (daily discharge, bi-monthly water quality) EXAMPLE

27. Integrating Monitoring Data into Models Tributary Loads P Evaluation Sites River Loads Reservoirs EXAMPLE

28. Wrap-Up • The scale of the Wisconsin River TMDL required more monitoring sites, frequency • Defining the question and the methods used at the start improved the project’s monitoring design. • Each part of the TMDL (monitoring, load calculations, watershed modeling) introduces uncertainty. In many cases, a robust monitoring dataset improves our understanding and limits the uncertainty with respect to the model results.

29. Questions? Contact the Wisconsin River TMDL Project Team dnrwisconsinrivertmdl@wisconsin.gov