Wabash River Nutrient and Pathogen TMDL Development Public Comment Meetings July 11, 2006: Huntington, Indiana July 12, 2006: Lafayette, Indiana July 12, 2006: Robinson, Illinois
Agenda • Introduction to TMDLs • Listing Information • Modeling Results • TMDL Allocations • Implementation • Discussion
Introduction to TMDLs Introduction to TMDLs
What is a TMDL? • TMDL is “Total Maximum Daily Load” � The amount of a pollutant a waterbody can receive and still achieve Water Quality Standards • Established under the Clean Water Act • Goal is restoration of Water Quality (due to pollutants) • Intended to address both point and nonpoint sources • Flexible • Developed with local involvement
WQS Drive the TMDL Process Water Quality Standards • Designated Uses • Numeric Criteria • Narrative
Indiana Water Quality Standards • E. coli � April 1st through October 31st, E. coli shall not exceed 1 2 5 per 1 0 0 m illiliters as a geometric mean based on not less than 5 samples equally spaced over a 30- day period nor exceed 2 3 5 per 1 0 0 m illiliters in any 1 sample in a 30-day period.
Indiana Water Quality Standards • Nutrients/ Organic Enrichment Benchmarks � Total phosphorus should not exceed 0.3 mg/ L � Nitrate + nitrite should not exceed 10 mg/ L � Dissolved oxygen should not be: � below 4.0 mg/ L (ever) � consistently higher than 12 mg/ L � less than 5.0 mg/ L as a daily average
Indiana Water Quality Standards • Nutrients/ Organic Enrichment Benchmarks (continued) � No pH values should be less than 6.0 or greater than 9.0. pH should also not be consistently close to the standard (i.e., 8.7 or higher) � Algae growth should not be “excessive” based on field observations by trained staff � More than one exceedance is necessary to determine impairment
Illinois Water Quality Standards • Fecal coliform � Based on a minimum of five samples taken over not more than a 30-day period, fecal coliform bacteria counts shall not exceed a geom etric m ean of 2 0 0 per 1 0 0 m l , nor shall more than 10 percent of the samples during any 30 day period exceed 4 0 0 per 1 0 0 m l � Applies during the months of May through October
Fecal Coliform/E. coli Translator • Need to assume relationship between fecal coliform and E. coli � Fecal coliform = 200/ 125 = 1.6 X E. coli • Based on the geometric mean components of the two state Total Coliform standards Bacteria • Both numbers meant to limit Fecal Coliform Illnesses to 8 swimmers per Bacteria 1000 Escherichia coli
The TMDL Process Water Quality Water Quality Water Quality Controls 303(d) List Standards Management Plan • List of impaired • Watershed Characterization • NPDES Permits • Designated Uses waters in need of • Water Quality Impairment • Voluntary Nonpoint • Numeric Criteria TMDLs Status Source BMPs • Narrative • Source Assessment • Others • Targets a “TMDL” • TMDL • Allocation • Margin of Safety • Monitoring Strategy • Restoration Strategy THE TMDL PROCESS
Listing Information Listing Information
Wabash River 303(d) Listings • Various segments in Indiana listed as impaired for E. coli , nutrients, pH, dissolved oxygen, and impaired biotic communities • Only one segment in Illinois listed as impaired due to fecal coliform • Comprehensive review of the water quality data � Suggested E. coli and fecal coliform impairments fairly common � Nutrient impairments primarily upstream • Holistic approach to TMDL development
Modeling Results Modeling Results
Why Model? • Clean Water Act requires TMDL to quantify allowable daily loads • Relationship between loads and resulting water quality is also necessary • Identification of key sources can greatly facilitate effective implementation planning • Assess potential restoration scenarios (e.g., increased use of nutrient management plans, new wastewater treatment plant permit limits)
Model Selection • CE-QUAL-RIV1 (or RIV1) � River model developed by U.S. Army Corps of Engineers • Allowed for a detailed analysis of spatial and temporal trends within the Wabash River • Facilitated making allocations to three general source categories: 1) National Pollutant Discharge Elimination System (NPDES) facilities that discharge directly to the Wabash River 2) Subwatersheds draining directly to the Wabash River 3) Significant Wabash River tributaries.
Modeling Process • Model setup � Develop the model data sets (tributary loadings, weather data, point source loadings, etc.) • Perform hydrologic and hydraulic calibration and validation • Perform water quality calibration and validation • Evaluate TMDL load reduction scenarios • Document results
Modeling Results: Hydrology Avg Observed Flow (2/1/1998 to 12/31/2002 ) Avg Modeled Flow (Same Period) 140000 0 120000 2 Daily Rainfall (in) 100000 4 Flow (cfs) 80000 6 60000 8 40000 10 20000 12 0 14 Feb-98 Feb-99 Feb-00 Feb-01 Feb-02 Date Example results: USGS gage 03341500 Wabash River at Terre Haute, Indiana
Modeling Results: Water Quality modeled observed 1 0.9 0.8 0.7 TP (mg/L) 0.6 0.5 0.4 0.3 0.2 0.1 0 Feb-01 Aug-01 Feb-02 Aug-02 Feb-03 Aug-03 modeled observed 2000 1800 1600 Ecoli (MPN/100mL) 1400 1200 1000 800 600 400 200 0 Feb-01 Aug-01 Feb-02 Aug-02 Feb-03 Aug-03 Example results: IDEM site WLV030-0003 (CR 700 W, Near Lafayette)
TMDL Scenarios • Calibrated model provided the basis for performing the allocation analysis • First used to project baseline conditions (“worst currently allowable” scenario) � NPDES facilities simulated as discharging daily at their design flows and at the maximum of their permit limits � CSO loads assumed equal to existing flows and concentrations at water quality standards � Full implementation of Ohio Wabash River TMDL
Modeling Results: TMDL Scenarios 0.6 0.5 Phosphorus benchmark Number of days Exceeding 0.4 TP(mg/L) Standards 0.3 Baseline: 72 days/year 0.2 Post-TMDL 0 days/year 0.1 0 Feb-01 May-01 Sep-01 Dec-01 Mar-02 Jun-02 Oct-02 Jan-03 Apr-03 Baseline Conditions Post-TMDL Conditions 10000 E. coli Standard 1000 Ecoli(#/100ml) Number of days Exceeding Standards 100 Baseline: 50 days/rec season 10 Post-TMDL 0 days/rec season 1 Feb-01 May-01 Sep-01 Dec-01 Mar-02 Jun-02 Oct-02 Jan-03 Apr-03 Baseline Conditions Post-TMDL Conditions Series1 Wabash River Upstream of Vermilion River
TMDL Allocations TMDL Allocations
TMDL Allocations • Clean Water Act requires that TMDL be allocated as follows: � TMDL = WLA + LA + MOS � WLA for “point sources” (regulated under NPDES) � LA for nonpoint sources and natural background � MOS for Margin of Safety • Wabash River TMDLs allocated to: 1)Point source facilities that discharge directly to the Wabash River 2)Subwatersheds draining directly to the Wabash River 3)Significant Wabash River tributaries
Wabash River TMDL Allocations • E. coli and Fecal Coliform � Relatively large load reductions needed for tributaries and subwatersheds draining directly to the Wabash River � No load reductions needed for point sources (permit limits already in place for larger facilities) • Nitrate � Upper Wabash less than benchmark assuming reductions from Ohio TMDL � Lower Wabash already less than benchmark • Phosphorus � Relatively minor reductions needed for tributaries and subwatersheds draining directly to the Wabash River � Point sources may be significant source of phosphorus, especially during low flow periods � Additional monitoring recommended to confirm this finding
Implementation • Implementation plans are expected to be developed and tailored to individual tributary watersheds as needed • A wide variety of best management practices will be needed: � Riparian area management � Manure collection and storage � Nutrient management plans � Urban stormwater management practices � Septic system management/ education • Other � Additional sampling of WWTP phosphorus loads � CSO allocations will be better refined in each city’s Long-Term Control Plan
Schedule Schedule
Wabash River TMDL Schedule • Draft TMDL Report: July 5, 2006 � http: / / www.in.gov/ idem/ programs/ water/ tmdl/ documents.html � http: / / www.epa.state.il.us/ water/ tmdl/ report-status.html • Public comment meetings: July/ Aug 2006 • Final TMDL Report: September 2006
(Watershed Specialists & 319 Coordinators) Indiana • Watershed Specialists � Upper Wabash � Tim Kroeker (317) 234-3312 � Middle Wabash � Linda Schmidt (317) 234-1432 � Lower Wabash � Bonny Elifritz (317) 234-0922 • 319 Coordinators � Upper Wabash � Kathleen Hagan (317) 233-8801 � Middle/ Lower Wabash � Pamela Brown (317) 234-3406
(Watershed Specialists & 319 Coordinators) Illinois • Watershed Specialists � Watershed Liaison with Association of Illinois SWCDs and Illinois EPA- Jim Nelson- (217) 744-3414 � Illinois EPA, Southern Illinois Watershed Specialist- Margaret Fertaly (618) 993-7200 • 319 Project Coordinator � Amy Walkenbach- (217) 782-3362
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