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2005 Stream Phosphorus TMDLs to be proposed in July 5th NJR

2005 Stream Phosphorus TMDLs to be proposed in July 5th NJR. The NJDEP’s Division of Watershed Management is seeking stakeholder input on proposed phosphorus TMDLs: Pre-proposal Outreach to Interested and Affected Entities

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2005 Stream Phosphorus TMDLs to be proposed in July 5th NJR

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  1. 2005 Stream Phosphorus TMDLs to be proposed in July 5th NJR The NJDEP’s Division of Watershed Management is seeking stakeholder input on proposed phosphorus TMDLs: • Pre-proposal Outreach to Interested and Affected Entities • To share subject impairments and approach relating water quality to pollutant loads • To request comments on approach and information regarding identification sources, and local initiatives to address sources

  2. Current Approach Focuses on Stream Impairments Where: Sufficient data on water quality and flow exist to develop relationship NPS are the primary source Streams are nontidal

  3. Watershed Management approachto TMDLs SWQS Compliance & Enforcement Monitoring Permit Limits NPS Controls Public Involvement Assessment TMDLs Impaired? 303(d) List/ Sublist 5

  4. What are TMDLs? • Total Maximum Daily Loads (TMDLs) represent the assimilative or load capacity of the receiving water, taking into consideration: • point sources of pollutants (wasteload) • nonpoint sources of pollutants (load) • natural background • surface water withdrawals

  5. How are TMDLs expressed? Amount of pollutants that a waterbody can assimilate without violating surface water quality standards or other target TMDL = WLA +  LA + MOS Where: WLA is the wasteload allocation LA is the load allocation and MOS is the margin of safety

  6. Margin of Safety (MOS) • A required component of the TMDL that accounts for any lack of knowledge concerning the relationship between effluent limitations and water quality (40 CFR 130.79(c)) • The MOS shall be expressed either as an internal modeling factor and/or as an explicit, separate factor (N.J.A.C. 7:15- 7.7(a))

  7. Source assessment characterization and quantification as necessary identify point, nonpoint and background sources Water quality analysis link pollutant sources & water quality: model consider seasonal variation / critical conditions TMDL calculations loading capacity margin of safety load and wasteload allocations Follow-up monitoring Implementation Public participation Components of a TMDL

  8. When Are TMDLs Done? • TMDLs are required, under Section 303(d) of the federal Clean Water Act, to be developed for waterbodies that cannot meet surface water quality standards after the implementation of technology-based effluent limitations

  9. 2004 Integrated List SUBLIST 1 & 2: FULL ATTAINMENT LIMITED ATTAINMENT DATA SUBLIST 3: INSUFFICIENT DATA TO ASSESS SUBLIST 4: IMPAIRED BUT: TMDL DONE IMPAIRMENT BY POLLUTION NOT POLLUTANT OTHER ENFORCEABLE MEASURESWILL ADDRESS SUBLIST 5: NON-ATTAINMENT 305(b) Report 303(d) List

  10. Target for TMDL: SWQS for Phosphorus (mg/L) Numerical Criteria • i. Lakes: TP not to exceed 0.05 in any lake, pond, reservoir, or in a tributary at the point where it enters such bodies of water, except where site-specific criteria are developed (N.J.A.C. 7:9B-1.5(g)3) • ii. Streams: TP not to exceed 0.1 in any stream, unless it can be demonstrated that TP is not a limiting nutrient and will not otherwise render the waters unsuitable for the designated uses.

  11. SWQS for Phosphorus (mg/L), continued Narrative Criteria--Nutrient policies are as follows: • Except as due to natural conditions, nutrients shall not be allowed in concentrations that cause objectionable algal densities, nuisance aquatic vegetation, abnormal diurnal fluctuations in dissolved oxygen or pH, changes to the composition of aquatic ecosystems, or otherwise render the waters unsuitable for the designated uses.

  12. TMDL Model Used:Flow-Integrated Reduction of Exceedances (FIRE) • Method must be selected to relate water quality to pollutant loading • FIRE uses site-specific water quality concentration and flow data to determine the actual load and the target load, which is the load that corresponds to attainment of the New Jersey Surface Water Standards. The technique compares actual loads to the target over the entire range of measured flows. Any units for loadings can be used in the regression.

  13. Target total phosphorus loading to maintain 0.1 mg/l TP concentration

  14. Illustration of FIRE Technique

  15. Load Capacity • The Load Capacity of the waterbody is represented by the Target Loading line • The Required Load Reduction is the difference between the slopes of the Exceedance Regression line and the Target Loading line • Margin Of Safety (MOS) is represented by the difference between the slopes of the Upper 95 percent confidence limit of the Exceedance Regression and the Exceedance Regression line and becomes an unallocated portion of the Load Capacity

  16. Load Reduction • The Overall Loading Reduction required is the summation of the Required Load Reduction to attain standards and the MOS and is represented by the difference between the slopes of the Upper 95 percent confidence limit of the Exceedance Regression and the Target Loading lines

  17. Allocating Load Reduction • Existing load is calculated by applying loading (or export) coefficients, which represent annual average loads from various land uses, to the areal extent of each land use in the drainage area, determined using GIS • WLAs and LAs are then derived from the allocable load, with LA reductions taken only from land uses where reductions are feasible • No reduction is taken from forest, wetland, water and barren land uses; these load contributions remain unchanged between existing and future scenarios

  18. UAL Methodology Pollutant Export Coefficients obtained from literature sources are applied to land use patterns: • Land Use determined by NJDEP’s 1995/97 GIS Coverage. • Phosphorus export coefficients selected for NJ from an extensive database to develop table on next slide.

  19. Phosphorus export coefficients(Unit Areal Loads)

  20. Example of FIRE Application

  21. TMDL Calculations • Load Capacity = (Slope C ÷ Slope B) x 100 = % of existing loadings • Total Overall Loading Reduction = (1 – (Slope C ÷ Slope A)) x 100 = % of existing loadings Land-Use Loading Reductions = (1 – (Slope C ÷ Slope B)) x 100 = % of existing loadings Margin of Safety = (1 – (Slope B ÷ Slope A)) x 100 = % of existing loadings Or, = (1 – (Slope B ÷ Slope A)) x (Slope C ÷ Slope B) x 100 = % of existing loadings as applied to Load Capacity • Percent Reduction of Adjustable Land-Use Loads = [1 - (Load Capacity – MOS – Non-Adjustable Land-Use Loads) ÷ Total Existing Loads] x 100 = [1 – ({Slope C ÷ Slope B} – {(1 – (Slope B ÷ Slope A)) x (Slope C ÷ Slope B)} – (fraction of Non-Adjustable Land-Use Loads))] x 100 = % of existing loadings

  22. Application of FIRE, continued Derived from Export Coefficients: Total Existing Loading = 1,000 lb/day Non-Adjustable Land-Use Loads = 50 lb/day Derived from FIRE: Slope A = 1.0705 (Upper 95% Confidence Limit of Exceedance Regression) Slope B = 0.8934 (Exceedance Regression) Slope C = 0.5390 (Target Loading, or Load Capacity) Application of Results from FIRE: Load Capacity = TMDL = 603 lb/day Total Overall Loading Reduction = 496 lb/day Margin Of Safety (MOS) = 166 lb/day of existing loading Or 100 lb/day of Load Capacity Adjustable Land-Use Load Reduction = 547 lb/day

  23. TMDL Loading (lb/day) Percent of Load Capacity (%) Percent Reduction of Existing Loadings (%) Load Capacity 603 100 Adjustable Land-Use Loads 453 75.1 = 453/603 x 100 54.7 = [1 – (453/1000)] x 100 Non-Adjustable Land-Use Loads 50 8.3 = 50/603 x 100 0.0 Margin of Safety 100 16.6 = 100/603 x 100 Summary of TMDL

  24. TMDL Implementation • For TMDL purposes, point sources include discharges to surface water that are subject to regulation under the Clean Water Act, National Pollutant Discharge Elimination System. • Point source reductions are accomplished through NJPDES permits: effluent limits or Phase II stormwater basic requirements, as well as additional measures, if appropriate

  25. TMDL Implementation • For TMDL purposes, nonpoint sources are those that are not subject to regulation under NPDES, including NJPDES Tier B municipal stormwater discharges • Nonpoint source reductions are achieved through implementation of management measures that can reduce loads, e.g. land use BMPs, NJPDES basic requirements and additional measures applied to Tier B municipal stormwater dischargers, etc.

  26. Resources for Implementation • Agricultural BMPs: EQIP, CRP, CREP • 319(h) grants for nonpoint source projects • Environmental Infrastructure Financing Program loans • Estuary Programs • Private grant programs

  27. Request for Input from Stakeholders Prior to Proposal: • Comment on Proposed TMDL Method • Identify Potential Sources in affected watersheds • Identify On-going Projects that would reduce phosphorus load in affected watersheds Comments due: June 24th Contact: Barbara Hirst or Kim Cenno at (609) 633-1441

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