Total Maximum Daily Loads TMDLs Yvonne Baker Water
Total Maximum Daily Loads (TMDLs) Yvonne Baker Water Permits Division LDEQ 1
TMDL Defined • TMDL = WLA + MOS § WLA = Waste Load Allocation for point source loads § LA = Load Allocation for nonpoint source load § MOS = Margin Of Safety (account for uncertainty/growth) • TMDLs establish the maximum amount of loading that a waterbody can assimilate while maintaining the established water quality criteria.
TMDL Defined TMDLs: • Can be developed for any parameter that can be expressed as a load • Set limitations on waterbodies based on established target values (standards or criteria) • Can be expressed as various statistical functions at various frequencies • Can be expressed in terms of load reductions through Best Management Practices (BMPs) when appropriate
TMDL Regulations • TMDLs requirements were established in Section 303(d) of the Clean Water Act; additional clarification is provided in the Code of Federal Regulations (40 CFR 130. 7) • States must: § identify impaired waters § establish priority ranking § establish TMDLs for those pollutants suspected to cause the impairments • TMDLs must be completed for all waterbody/parameter combinations, but a higher priority is given to impaired waterbodies. • If states do not develop TMDLs for impaired waters, EPA will.
Primary Steps in TMDL Development • Waterbodies are defined as regulatory subsegments by Louisiana’s Environmental Regulatory Code (ERC 33: IX. 1123). • Waterbodies defined as subsegments are assessed as part of the 305(b) report • Waterbodies that fail their assessments are placed on the 303(d) list and scheduled for TMDL development
Primary Steps in TMDL Development • Collect and analyze all needed data. § Gather all available hydrologic data, water quality data, and stream characterization information. § Conduct field surveys - particularly for dissolved oxygen TMDLs. • Calculate TMDLs, WLAs, and load reductions. For dissolved oxygen and possibly fecal coliform, this involves the development of computer models. • Write the draft report • Public review • Address comments and finalize the TMDL • EPA approval (only for impaired waterbodies)
MS 4 s in Louisiana Kimberly Corts LDEQ/Water Permits Division
How is Storm Water Regulated Under the LPDES Program? Phased approach to regulation consistent with federal regulations: – Phase I: Regulated discharges from large and medium MS 4 s, large construction projects, and industrial activity - § 402(p)(2) – Phase II: Regulated discharges from small MS 4 s and small construction projects § 402(p)(6)
List of LA MS 4 Permittees • Large and Medium MS 4 s (Individual Permit Coverage): – 4 large MS 4 s are permitted – New Orleans, Baton Rouge, Shreveport, and Jefferson Parish • Small MS 4 s: – Covered under the general permit, LAR 040000 – 44 MS 4 s have obtained coverage
2010 Census • Currently, permitted MS 4 s were required to obtain coverage based on the 2000 census • Based on the 2010 census several communities have been identified as needing permit coverage and will be required to develop a Storm Water Management Plan and many currently permitted areas have expanded. • The urbanized area maps are used as the basis for MS 4 requirements, although LDEQ may designate MS 4 s using other population information
MS 4 GIS Layer
Permitting Challenges • TMDLs have recently been developed/approved in heavily impacted areas – East Baton Rouge, Livingston, Ascension Parishes and along the north shore of Lake Pontchartrain that include allocations for MS 4 s • EPA intends on proposing a new rule in 2013, which could change the requirements for small MS 4 s – who is considered “regulated”, new construction/redevelopment requirements, etc
Upcoming TMDL Changes
Urban Pollutants Associated with MS 4 s • Sediment from Construction Sites • Oil and Grease From Parking Lots and Streets • Nutrients and Pesticides from Lawns and Golf Courses • Storm water runoff from all existing and new development (residential and commercial) • Metals such as dissolved lead caused by atmospheric deposition
EPA’s 2002 Guidance Memorandum Regarding Wasteload Allocations for Stormwater Sources • “National Pollutant Discharge Elimination System (NPDES)regulated stormwater discharges must be addressed by the wasteload allocation (WLA) component of a TMDL. ” • “NPDES-regulated stormwater discharges may not be addressed by the load allocation (LA) component of a TMDL. ” • “Stormwater discharges from sources not currently subject to NPDES regulation may be addressed by the load allocation component of a TMDL. ”
EPA’s 2002 Guidance Memorandum Regarding Wasteload Allocations for Stormwater Sources • “It may be reasonable to express allocations for multiple point sources as a single categorical wasteload allocation when data and information are insufficient to assign each source or outfall individual WLAs. ” • The WLAs and LAs are to be expressed in numeric form. • Most effluent limits for MS 4 permittees and small construction stormwater discharges will be in the form of BMPs; numeric limits used only in rare instances.
2010 Update to the 2002 EPA Memorandum • Numeric WQBELs can clarify permit requirement and improve accountability and enforceability, based on the discretion of the permitting authority. • WLAs for stormwater sources should be disaggregated in order to establish clear, effective, and enforceable NPDES permit limitations. • Stormwater limitations may be established through the use of surrogate parameters-ex. turbidity vs. TSS. • Permitting authorities should consider designating stormwater sources not currently regulated by NPDES permits as candidates for regulation.
ACWA Response to EPA’s 2010 Update to the 2002 Memorandum • ACWA (Association of Clean Water Administrators) was formerly known as ASIWPCA (Association of State and Interstate Water Pollution Control Administrators) • Implementation of 2010 memo will be difficult for many states. • Treating stormwater like point source effluent will “fail in achieving significant environmental benefits”. • “Cost effective, environmentally sound, and sustainable stormwater management is possible when the realities and uncertainties of stormwater science are acknowledged, and the “point source” NPDES regulatory framework is reworked to include this science. ”
ACWA Response to EPA’s 2010 Update to the 2002 Memorandum • Incorporating numeric limits into stormwater permits will be challenging – not all states have the resources (technology and funding) to do so. • “States should be afforded significant flexibility to establish numeric effluent limitations in stormwater permits as part of this memorandum. ” • ACWA encouraged “EPA to consider the significant benefits that exist in regulating precipitation-driven discharges in a fundamentally different way than traditional, end of pipe, process waste point source discharges. ”
Court Decision Regarding the Accotink TMDL • • Impairment was for sediment. EPA established a TMDL in 2011. TMDL used flow as a surrogate parameter for sediment. On January 3, 2013, the United States District Court for the Eastern District of Virginia issued its decision, vacating the TMDL. • The Court held that EPA lacked the authority under Section 303(d) of the Clean Water Act to establish the Accotink TMDL using the Creek’s one- year, 24 - hour storm flow rate, a non-pollutant measure, as a surrogate for the pollutant sediment. • EPA has decided not to appeal, based largely on the fact
LDEQ Interim Solution • Dissolved oxygen TMDLs: § the critical low flow is 7 Q 10, stormwater is not present at that time. § Include statements indicating that the allocation for all stormwater loading from point sources is 0. 0 lb/day under critical flow conditions. § Allocate a portion of the nonpoint load to the MS 4 based on drainage area ratios. § Include statement that the load is not to be interpreted as a permit limit
LDEQ Interim Solution • LDEQ realizes that this will not be adequate for all cases. • Future TMDLs § may include dynamic modeling to account for storm events. § may be developed for high flow conditions. • Reevaluate and revise criteria where appropriate
In Summary • EPA guidance and recommendations have indicated a desire for numeric limitations for MS 4 s. • This may be very costly for MS 4 permittees due to the increase in monitoring sites and frequency. • TMDLs may require the development of dynamic/spatial models which are very complex and resource intensive. • EPA is revising stormwater regulations; intends to propose revisions by June, 2013.
Complying with the TMDL Requirements Recent DO TMDLs (Bayou Manchac, Gray’s Creek, Bayou Lacombe, Tchefuncte River, etc. ) specify that BMPs are the most appropriate method of addressing the TMDL to reduce the nonpoint source loading as well as eliminate illicit discharges.
LAR 04 Requires… Permittees must document in their SWMP how the BMPs and other controls implemented in the SWMP will control the discharge of any pollutant(s) of concern (POCs) for discharges into a receiving water which has been listed on the Clean Water Act 303(d) list of impaired waters. If a TMDL has been approved for a waterbody, the permittee will be required to include any TMDL requirements in the SWMP that are applicable to Documentation is the key…. MS 4 discharges.
LAR 04 Requires… If a TMDL allocation has been assigned for specific pollutants, which are identified as impairments attributed to discharges from regulated MS 4 s, then the permittee must modify the storm water management program to implement the TMDL within six months of the TMDL’s approval or as otherwise specified in the TMDL. This requirement includes TMDLs that are developed during the term of this general permit. In addition to any MS 4 -specific requirements of the TMDL, the permittee must also: 1) implement storm water controls that specifically target the pollutant(s) of concern 2) identify a measurable goal for the pollutant(s) of concern and 3) implement a monitoring program to assess whether or not the storm water controls are adequate to meet the WLA.
Part IV. H Impaired Waterbodies with an Approved TMDL If a Waste Load Allocation (WLA) has been assigned to discharges of a particular pollutant from your MS 4 to a particular basin subsegment: 1. You must include specific and measurable goals in your SWMP targeting the pollutant(s) of concern. Include details, such as identifying areas of focused effort or implementing additional control measures or BMPs that will reduce the pollutant(s) of concern. A schedule for implementing each targeted control shall be included in the SWMP.
Part IV. H Impaired Waterbodies with an Approved TMDL 2. The permittees shall adopt any assigned Waste Load Allocations (WLAs) as a benchmark goal in the SWMP. The benchmark goal is not a permit limit, but shall be used to measure the progress towards achieving pollutant reductions from the MS 4. If the benchmark goal is met, the permittee shall maintain the control measures, BMPs, or other pollutant reduction programs necessary to ensure the goal will continue to be met. 3. If applicable, the permittee must comply with monitoring or compliance schedules established in the TMDL.
Part IV. H Impaired Waterbodies with an Approved TMDL 4. The permittees shall select one or more of the following recommended controls, or develop other controls that may best achieve the pollutant reduction goals. The following storm water control measures address nutrient, dissolved oxygen, sediment, and/or bacteria impairments. a. Prioritize the detection and elimination of illicit ontributing discharges MS 4. b. Implement public education measures to reduce the discharge of bacteria and nutrients contributed by pets, livestock, and zoos.
Part IV. H Impaired Waterbodies with an Approved TMDL c. Implement a public education program to reduce the discharge of nutrients from the over application of residential and commercial fertilizers. d. Implement programs to reduce the pollutant contributions to the MS 4 from failing on-site sewage treatment systems, such as septic tanks and small package plants. Such a program could include requiring the replacement of old septic tanks, regionalization of heavily populated areas without a centralized waste treatment facility, and/or extension of existing sewage treatment lines.
Part IV. H Impaired Waterbodies with an Approved TMDL e. Implement programs to enhance the MS 4’s sanitary sewer systems. Such a program should address inadequate collection systems, malfunctioning lift stations, or violations of the sewage treatment plant’s water discharge permit. f. For construction activities, require a minimum buffer zone adjacent to surface waters to reduce erosion and sediment runoff.
Part IV. H Impaired Waterbodies with an Approved TMDL 5. You must implement a monitoring program to determine whether the storm water controls that you have selected are adequate to meet the WLA. Each permitted MS 4 must develop a monitoring program that is specific to the selected BMPs and will be an effective tool to determine if measurable goals are being met. Document in your SWMP the reason and justification for the parameters and frequencies selected and how the monitoring program will effectively evaluate storm water controls. Monitoring programs may include, but are not limited to, the following elements:
Part IV. H Impaired Waterbodies with an Approved TMDL a. Regular visual inspections of outfalls during wet and dry weather; b. Regular inspections of receiving water bodies with the purpose of noting erosion or sedimentation problems; c. Regular inspections of storm drains, major canals, or junctions; d. Visual inspections of effluent samples for color, clarity, and the presence of foam, oil, debris, or noxious odors;
Part IV. H Impaired Waterbodies with an Approved TMDL e. Instantaneous (in situ) water quality measurements of the receiving water body, such as dissolved oxygen, temperature, p. H, etc. ; and f. Sampling and analysis of storm water discharges for pollutants of concern. The permittee must also conduct any monitoring, including specific frequencies, required by applicable TMDLs.
Part IV. H Impaired Waterbodies with an Approved TMDL 6. The permittees must evaluate the effectiveness of the storm water management program and document progress towards the benchmark goal(s). The MS 4 operator may utilize third party data, such as that collected by LDEQ, USGS, EPA, and volunteer organizations in the evaluation process. However, the evaluation shall not be limited to only third party data. If subsequent evaluations show that additional or modified controls are necessary to meet the WLA for a particular pollutant then you must describe the additional or modified controls that will be implemented and include a schedule for implementation. You must continue to evaluate the adequacy of the BMPs that you have implemented to meet the WLA for a particular pollutant. Make modifications to the SWMP as necessary until monitoring for a full permit cycle shows that the WLAs are being met or that the MS 4 is no longer contributing to the water quality impairment.
Monitoring • Monitoring does not necessarily refer to laboratoryanalyzed samples only • Regular visual inspections of outfalls are acceptable! • Some storm water samples may be taken to establish overall load coming from the MS 4 (BOD, COD, TSS, possibly nutrients) • Frequencies and types of monitoring are established by the MS 4 permittee
What is an outfall? An outfall is the point at which any conveyance of a storm sewer system discharges to surface waters of the state – does not include pipes, tunnels, or ditches that connect two storm sewers. DOTD outfalls are a little different and may include bridges that cross water bodies.
Bayou Manchac and other Lake Pontchartrain Basin TMDLs • New Dischargers: § Submit an environmental impact assessment § Upon evaluation of the factors associated with the environmental impact assessment: o Permits with 5 BOD 5/ 2 NH 3/ 5 DO; or limits not to exceed 10 BOD 5 /2 NH 3 -N o No discharge scenarios (flow elimination, effluent reduction, hydrographic release, reuse) 40
Bayou Manchac and other Lake Pontchartrain Basin TMDLs • Existing Dischargers: § Up to 3 year compliance schedule § More stringent limitations o Facilities currently with limitations of 30 BOD 5 will receive limitations of 10 BOD 5 o Facilities currently with limitations of 10 BOD 5 will receive limitations of 5 BOD 5 41
Bayou Manchac and other Lake Pontchartrain Basin TMDLs • MS 4 regulated areas § expected to use BMPs to address documented impairments and TMDLs § BMPs may include: o Public education o Projects to reduce impervious surfaces o Retention ponds o Storm drain traps o Location/elimination of unpermitted dischargers 42
Options for Affected Parties • • Regionalization Local Ordinances Wetland Assimilation Innovative Technologies for no discharge scenarios 43
Regionalization • More affordable treatment option § Cost per gallon of wastewater decreases as treatment capacity increases • Fewer treatment facilities to operate and maintain • Potentially fewer waterbodies impacted • Moves discharges out of neighborhood ditches 44
Local Ordinances • Require approval from DEQ prior to issuing building permit § Request for Preliminary Determinations § Receive Final Permit Before Construction • Do NOT allow developers to utilize individual home treatment units when developing subdivisions. 45
Wetland Assimilation • Benefits of a Wetlands Assimilation Project for the Environment – Removes direct discharges of treated wastewater into state waterbodies – Can help prevent saltwater intrusion into the wetland – Add an abundance of needed nutrients into the wetland to stimulate plant growth – Carbon sequestration • Benefits for a Permittee – Less operations and maintenance costs – Secondary Limitations – A “green” approach to wastewater treatment • Link to Wetlands Assimilation Webpage: http: //www. deq. louisiana. gov/portal/tabid/2960/Default. aspx 46
Innovative Technologies • No Discharge Scenarios § Recycle § Reuse • Hydrographic Release 47
Websites Access to Louisiana TMDLs or notifications can be obtained at: http: //www. deq. louisiana. gov/portal/default. aspx? tabid=1563 http: //www. epa. gov/region 6/water/npdes/tmdl/index. htm http: //louisiana. gov/Services/Email_Notifications_DEQ_TMDL/
Contact Information Yvonne Baker Environmental Scientist Senior 225. 219. 3193 yvonne. baker@la. gov TMDL contact– Chuck Berger, DCL Senior 225. 219. 3366 chuck. berger@la. gov
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