Lower Boise Stormwater TMDL Summary 0311

Lower Boise Stormwater Monitoring and Implementation Summary :

Lower Boise Stormwater Monitoring and Implementation Summary Lower Boise Watershed Council March 10, 2011

Presentation Goal:

Presentation Goal Provide the LBWC an overview of: National Stormwater Program Lower Boise TMDLs Lower Boise Stormwater Monitoring and Implementation Summary National Program Direction

National Stormwater Program:

National Stormwater Program 1987 Clean Water Act Amendments New National Stormwater NPDES Permitting Program (Section 402(p)) for: Municipal (MS4) Phase I (1990) >100,00 Phase II (1999) >10,000 Maximum Extent Practicable (MEP) controls Industry (MSGP) 11 industrial categories (1992, Airports, mining, manufacturing, landfills, power plants…) 29 industrial sectors Multi-sector General Permits (MSGPs) Technology based controls (numeric “benchmarks”) Construction (CGP) >5 acres (1992, now >1 acre) Construction General Permit (CGP) Technology based controls (numeric “benchmark”

Stormwater in Lower Boise Watershed:

Stormwater in Lower Boise Watershed MS4 Permits One Phase I: Boise (2000, MEP) Eight Phase II: Nampa-Boise Urbanized area (10/09, MEP) 3 municipalities (Caldwell, Middleton, Nampa) 5 Highway Districts (ACHD, Nampa, ITD, Notus-Parma, Nampa) MSGPs (e.g. Simplot; Micron; Boise Airport…) CGPs (> 1 acre)

Lower Boise Watershed TMDLs:

Lower Boise Watershed TMDLs TMDLs Sediment and Bacteria TMDLs (2000) Stormwater addressed Near Final 2010 Integrated Report Category 5 (TMDL Required) Temperature (Lucky Peak to mouth) Phosphorus (Middleton to mouth) Delist Sediment (Diversion Dam to Eagle Island) Phosphorus (Eagle Island to Middleton)

Boise MS4 Permit:

Boise MS4 Permit Applications 1992: separate applications 1994: joint co-permittee application, Amended in 1996 and 1999 Permit: Nov 29, 2000 to six co-permittees Legal authority STW & Erosion and Sediment Control Ordinances 11 SWMP Elements Structural Controls (design manuals) Floatables (litter) New and Redevelopment (design standards) Roadways Flood Management Pesticide, Herbicide, & Fertilizer Application Illicit Discharge Spill prevention and response Industrial and High Risk Runoff Construction Site Runoff Public Education Monitoring & Reporting

Boise MS4:

Boise MS4 Ten years of implementation Mature program, Robust new/redevelopment and Erosion & Sediment Control elements 2010 Funding: $1.848 million (6 agencies)

Instantaneous E. coli Data:

Instantaneous E. coli Data

E. coli Geomean Results:

E. coli Geomean Results

New Boise MS4 Draft Permit:

New Boise MS4 Draft Permit Maintain/Improve Existing Program New Requirements In General: Greater level of detail/rigor for each minimum measure 6 Minimum Controls instead of 11, Same monitoring approach Watershed planning (2 in 5 years) CGP referral to EPA Offset program for projects retaining <100% runoff Green Infrastructure/LID Strategy and Pilots Parking lot retrofits; Effectiveness monitoring Riparian Zone management/Outfall Disconnection Infrastructure and Street Inventory/tracking (GIS based) Public Ed: Landscapers/homeowner/property mgr fertilizer/pesticide program Assessment of Pub Ed effectiveness

MS4 Phase II Permits:

MS4 Phase II Permits Eight Phase II permits in Nampa-Boise Urbanized Area October 2009; MEP 3 municipalities (Caldwell, Middleton, Nampa) 5 Highway Districts (ACHD, Nampa, ITD, Notus-Parma, Nampa) Develop Stormwater Management Program (SWMP) Six Minimum Measures Public Education and Outreach Public Involvement and Participation Illicit Discharge Detection and Elimination Construction Site Runoff Control Post Construction Management for New & Redevelopment Pollution Prevention and Good Housekeeping Monitoring Review and Update SWMP

National Program Direction:

National Program Direction 2008 National Research Council Report November 12, 2010 Stormwater Guidance Stormwater Rule Revision

National Research Council Urban Stormwater Report:

National Research Council Urban Stormwater Report “[Stormwater has] degraded water quality and habitat in virtually every Urban stream system . The Clean Water Act regulatory framework for addressing sewage and industrial wastes is not well suited to the more difficult problem of stormwater discharges. This report calls for an entirely new permitting structure that would put authority and accountability for stormwater discharges at the municipal level . A number of additional actions, such as conserving natural areas, reducing hard surface cover (e.g., roads and parking lots ), and retrofitting urban areas with features that hold and treat stormwater, are recommended .” 2008 Report in Brief

NRC Urban Stormwater Report Recommendations:

NRC Urban Stormwater Report Recommendations Shift focus from pollutants to flow & impervious surface EPA should: advance the stormwater program (LID, watershed permitting & monitoring…) use license authority to control products Use market based trading Monitoring improvements industrial monitoring to establish benchmarks and technology-based standards instream monitoring to assess progress, effectiveness, & identify priorities flow and impervious surface instead of pollutants

2010 EPA Stormwater Guidance:

2010 EPA Stormwater Guidance Revision of 2002 guidance Establishing TMDL WLA for Stormwater Sources and Permit Requirements Four Key changes Numeric water quality based effluent limits MEP replaced by "as necessary for compliance with water quality standards.” Schedules of Compliance (SOCs) to meet TMDL driven permit limits Individual Stormwater Loads in TMDL WLAs WLAs by category (MS4s, construction, industrial, ...), Permits with numeric limits for each source Surrogates for Stormwater pollutant in TMDLs Regulate “flow” as a surrogate Designate additional stormwater sources and assign WLAs Recommends use of existing benchmarks as numeric limits

EPA Stormwater Rulemaking :

EPA Stormwater Rulemaking December 2009 EPA announced stormwater rulemaking Questionnaires and listening sessions 2010 Proposed Regulation September 2011 Final Regulation 2012 Five Areas of Interest: Extended Geographic Scope Substantive Post-Construction Same Requirements for Phase I and II MS4s Retrofitting Sensitive Waterbodies

Questions:

Questions