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West Virginia Department of Environmental Protection. Draft TMDL Public Meetings August 6, 2012. Middle Ohio North Watershed TMDLs. TMDL/ water quality standards recap Overview of this TMDL effort Explanation/demonstration of electronic documents, spreadsheets, tools
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West Virginia Department of Environmental Protection Draft TMDL Public Meetings August 6, 2012 Middle Ohio North Watershed TMDLs
TMDL/ water quality standards recap • Overview of this TMDL effort • Explanation/demonstration of electronic documents, spreadsheets, tools • Questions and Answers Agenda
“Total Maximum Daily Load” • How much pollutant a stream can receive and remain healthy • A Pollution Budget – prescribes reduction of pollutants (where needed) that result in the restoration of an impaired stream • TMDL development is required by the Clean Water Act for all streams impaired by a pollutant What’s a TMDL?
Stream that doesn’t meet water quality standards • WV Water Quality Standards are codified in 47CSR2 • Standards include “Designated Uses” for WV waters and the criteria to protect those uses • Water Quality Criteria can be numeric or narrative What’s an Impaired Stream?
Criteria of Concern • Fecal Coliform • Water Contact Recreation; Public Water Supply • 200 counts/100ml as a monthly geometric mean • no more than 10% of samples in a month exceed 400 counts/100ml • Total Iron • Aquatic Life/Public Water Supply • Not to exceed 1.5 mg/l as a 4 day average concentration more than once in a three year period
Biological Impairment • Conditions Not Allowable in State Waters • (47 CSR 2-3.2i) “.....no significant adverse impact to the chemical, physical, hydrologic or biological components of aquatic ecosystems shall be allowed.” • Benthic macroinvertebrate assessment • West Virginia Stream Condition Index (WVSCI) Criteria of Concern
S = “sum of” • WLA = “wasteload allocations” • LA = “load allocations” • MOS = “margin of safety” • WLAs - pollutant loads for “point sources” • Discharge from point • Need NPDES permit • LAs - pollutant loads for “nonpoint sources” and background • Precipitation and runoff • No permit required TMDL = S WLA + S LA + MOS
Project Timeline: • Proposed streams advertised for public comment April 2008 • Initial Public Meetings (TMDL Intro) May 2008 • Watershed Monitoring and Source Tracking July 2008 - June 2009 • Status Update Meeting August2011 • Draft TMDL Public Meeting Today TMDL Development History
Impaired Waters 160named streams – See Table 3-3 beginning on page 20of Draft Report for a complete list of streams and impairments
MDAS (Mining Data Analysis System) • Fecal Coliform, iron • Can handle point and nonpoint sources (representation and allocation) • Recognizes exposure duration and exceedence frequency components of criteria Modeling
Modeling 9 TMDL watersheds 434 subwatersheds
Design precipitation period Hourly precipitation data for a six-year period Design period includes wet and dry years Applied to present day land uses Permitted discharges equal to permit limits Baseline Condition Annualprecipitation totals for the West Union (WV9458) weather station
Existing pollutant sources reduced such that TMDL endpoints are achieved in each modeled subwatershed recognizing • Criteria value, duration and exceedence frequency • Margin of safety TMDL Condition
Required component of TMDLs • Explicit 5% used in most TMDLs • TMDL endpoints for numeric criteria are 95% of criterion value (example 1.425mg/ml for 1.5 mg/ ml criterion) Margin of Safety
Streambank erosion Upland Sediment Sources Harvested Forest Oil and Gas Agriculture Urban Residential Active Mining Pollutant Sources (Iron)
Streambank Erosion reduced to reference stream loadings • Mining point sources set to WQ at end of pipe • Sediment sources set to iron loadings equivalent to 100 mg/l TSS Iron Reduction Strategy
Future growth for Construction Stormwater throughout the impaired watershed drainage was reduced to 1% to allow for existing sources • If still impaired headwaters areas reduced to 0.5% • If still impaired then headwater areas only were reduced to 0% • If further reductions needed then (non headwater) CSGP areas reduced incrementally reduced from 0.5 to 0.0 % • If further reduction needed then dominant land sources were reduced until endpoint is met. • Nonpoint source reductions did not result in LA lower than background • Point Source reductions did not result in WLA more stringent than water quality standards end of pipe Iron Reduction Strategy continued
Fecal Coliform • STP effluents represented at existing limits (200/400) • Failing/nonexistent on-site sewage systems – 100% reduction • Combined Sewer Overflows (CSOs) - reduced to water quality criteria (200/400 cts) • Sensitivity Analysis based reductions • Urban runnoff • Agriculture Fecal Pollutant Sources & Strategy
Stressor identification • Define potential stressors/ pathways • Evaluate chemistry, habitat, field notes, bugs • Determine stressors • Stressor/TMDL Linkage • Organic Enrichment ......Fecal Coliform surrogate • Sediment …….Total Iron surrogate Biological Impairment TMDLs Table 4-2, Page 36 Linkage
All biologically impaired streams for which organic enrichment is a significant stressor are also impaired for fecal coliform • Implementation of fecal coliform TMDL will require removal of untreated sewage and animal wastes and thereby remove organic enrichment stress • Fecal TMDL is an appropriate surrogate Organic Enrichment Stressor
Reference Stream Method (previous approach) Select unimpaired reference watershed with similar landuse, ecoregion, geomorphological characteristics Normalized sediment loading in reference watershed is TMDL target for biologically-impaired stream Present Sediment TMDL • TSS/Iron correlation Method (current approach) • Correlate TSS and Iron • Model Iron • Present Iron TMDL • Calculate TSS reduction for Fe TMDL • Compare to TSS reduction needed for iron TMDL to reference approach reductions Sedimentation Stressor
All biologically-impaired streams for which sedimentation is a significant stressor are also impaired for iron Sediment reduction needed to meet iron water quality criteria is larger than that needed under reference watershed approach Iron TMDLs are appropriate surrogate Sedimentation Stressor
Sedimentation Stressor Table 8-1 on page 67 of the Draft Report
New facility anywhere in watershed if meeting water quality criteria end of pipe • New sewage discharges w/ 200/400 fecal coliform effluent limits • Subwatershed-specific future growth allowances have been provided, where possible, for site registrations under the Construction Stormwater General Permit • Full details on Future Growth can be found on page 107 of the Draft report Future Growth Highlights
Public Comment period ends August 25, 2012 • Documents may be reviewed/downloaded from DEP webpage http://www.dep.wv.gov/WWE/watershed/TMDL/Pages/default.aspx • CD available upon request – CD includes GIS Shapefiles and Technical Report • Comments should be submitted to Steve Young at Stephen.A.Young@wv.gov • Questions - contact Dave Montali, Jim Laine, Mike McDaniel • (304) 926-0499 (Ext 1063, 1061, 1055) • David.A.Montali@wv.gov, James.C.Laine@wv.gov, • Michael.L.McDaniel@wv.gov Public Comment
TMDL Products • Main Report – Overall description of the TMDL development process for streams in the Middle Ohio River North and South watersheds • Technical Report with detailed appendices
TMDL Products • Allocation spreadsheets: • Fecal Coliform, Iron • TMDL for each stream, WLAs and LAs by SWS • Filterable • GIS shapefiles, along with Technical Report and Appendices, available on CD