Redwood River TMDL Critique David De Paz, Alana Bartolai, Lydia Karlheim

Introduction Redwood River The Redwood River is impaired for both aquatic life and aquatic recreation due to fecal coliform and turbidity. Our critique is on the TMDL for bacteria. 8 reaches of the Redwood River fail to meet the water quality standard for bacteria (E. coli). [MPCA]

Watershed Characteristics Redwood River Area: 705 sq. mile Tributary to the Minnesota River The impaired reaches are classified as: 2B 2C 3B 7 2B 2C Recreation of all kind/aquatic life Aquatic life support and recreation stringent Less stringent General industrial purposes Limited resource value Note: Class 7 streams had not been assessed in this draft report but will be in 2010.

Land Use Redwood River Land Use – 85.5% Agriculture – 2.5% urban/Residential Artificial drainage

Bacteria Redwood River Causes in the watershed: failing septic systems -there are 1,948 subsurface sewage treatment systems. 1,051 are deemed “failing”, 334 are deemed “threats to public health” wastewater treatment plant bypasses and flushes (there are 8 WWTP) unsewered communities livestock waste from feedlots land applied manure (98% of total) Domestic pets and wildlife Standard only valid April -October Class 2B/2C (organisms/100 mLs) Class 7 (organisms/100 mLs) E. coli Fecal coliform [wolfenotes.com]

Sampling Sites Redwood River [USEPA, 2011] ‘99 ‘03-’06 ‘99 ’99-’06 ‘99 ’99-’06 ‘74-’06 Sites sampled by the MPCA and the Redwood- Cottonwood Rivers Control Area (RCRCA)

Fecal Coliform Redwood River [MPCA] Time Period: (geometric mean by reach)

TMDLs were calculated for each of the 8 reaches at each flow condition (helpful for BMP implementation). TMDL= ∑ (WLAs + ∑ LAs + MOS + RC) TMDL Development Redwood River point sources nonpoint sources accounts for uncertainty future development

TMDL Allocation WLA & LA Redwood River Likely non-point sources Land-applied manure inadequate human WW treatment Non-permitted municipal stormwater systems Pets/wildlife

TMDL Allocation MOS & RC Redwood River

TMDL Allocations West line to Threemile Creek [MPCA] Land use : 82.3 %cultivated 10.9 % urban 4.2 % grass 2.0 % forest 0.5% water/wetlands 1 WWTF with MS4 permit covering 2.86 % of the entire watershed No feedlots with NPDES permits 5472 animal units without permits 140 SSTS units with 56 are failing.

TMDL Allocations West line to Threemile Creek [MPCA]

TMDL Required Reduction West line to Threemile Creek [MPCA] 58.42% 69.65% 60.32% 60.55% 0% Inadequate data Inadequate data

Load Duration Curve West line to Threemile [MPCA]

Implementation and BMPs Redwood River [MPCA] BMPs: CRP buffers alternative tile intakes grassed waterways livestock exclusion sediment basins nutrient management plans wetland restorations streambank stabilization Goal: Achieve water quality standards for fecal coliform bacteria within 10 years by educating, training, and providing monetary incentives. Note: Specific implementation plan will be made after TMDL gets approved

Critiques & Assumptions : Fecal Coliform/ E.coli Unknowns of Fecal Coliform: Survival rates Fecal coliform may be higher when stream bed is aggravated (i.e. scouring events, runoff) [Davis et al.,2005] [

Critiques & Assumptions: Fecal Coliform Fecal Coliform vs. E.Coli Standard is normalized based on comparison studies by MPCA showing that 63% of fecal coliform will be E.Coli. E. coli samples converted using 179 E. coli = 200 cfu meaning that 89.5% of fecal coliform will be E. Coli. Substantiated using 35 sample pairs from the same Watersheds between [MPCA] Standard only valid April -October Class 2B/2C (organisms/100m Ls) Class 7 (organisms/100m Ls) E. coli Fecal coliform

Critiques & Assumptions: Flow Several reaches don’t have sufficient flow monitoring data USGS gage stations were used to find missing flow data Duration of monitoring data varies between stations [USEPA, 2011] ‘99 ‘03-’06 ‘99 ’99-’06 ‘99 ’99-’06 ‘74-’06

Critiques & Assumptions Implementation BMPs: CRP buffers alternative tile intakes Grassed waterways livestock exclusion sediment basins nutrient management plans wetland restorations streambank stabilization Livestock manure has environmental and economic benefits: Less prone to erosion Reduces commercial fertilizer Wetland restorations affects farmers Streambank stabilization Can be expensive Livestock exclusions Requires fencing and more management

Strength Required Reduction West line to Threemile Creek- site with largest reduction [MPCA] 58.42% 69.65% 60.32% 60.55% 0% Inadequate data Inadequate data

Strengths TMDL broken up by flow and reach 4 of the 8 reaches analyzed were not yet on the 303d list, but were included for thoroughness Entire portion of report focuses on understanding E. coli sources Willingness to reevaluate plan if/when changes occur ( i.e. population growth) [MPCA]

Questions? [confusedcow.webs.com]