U.S. EPA Presentation Stormwater Program Update

Transcription

1 U.S. EPA Presentation Stormwater Program Update Prepared by: Bob Newport, NPDES Programs Branch, U.S. EPA Region 5 Presented by: Christe Alwin, MS4 Program Specialist, Lansing District Office, DEQ

2 Stormwater Program Update Topics Federal Effluent Guidelines for Stormwater Discharges at Construction Sites U.S. EPA Stormwater Rulemaking

3 Effluent Guidelines Stormwater Discharges from Construction Sites EPA is proposing changes to the 2009 Final Rule addressing stormwater discharges from Construction and Development sites These changes are being made subsequent to a settlement agreement The proposed rule would make several revisions to the non-numeric (BMP-based) requirements of the existing rule, as well as withdraw the numeric discharge standards for turbidity (which are currently stayed)

4 Background: Construction & Development Stormwater Effluent Guidelines The DEQ integrates Part 91 (Soil Erosion and Sedimentation Control Program) and the Construction Stormwater Program administered through Permit-by-Rule. The DEQ will review the C&D rule non-numeric requirements and evaluate if updates are necessary to ensure Michigan s Permit-by-Rule is consistent with the effluent guidelines.

5 Background: Construction & Development Stormwater Effluent Guidelines Summary of C&D rule non-numeric requirements Erosion and Sediment Controls: Minimize: Sediment discharges Soil exposed during construction activity Disturbance to steep slopes Minimize soil compaction (related to post-construction infiltration) Control runoff volume on-site to minimize erosion Provide natural buffers Utilize outlet structures that withdraw water from the surface when discharging from basins, unless infeasible

6 Background: Construction & Development Stormwater Effluent Guidelines Summary of C&D rule non-numeric requirements Site Stabilization Initiate stabilization immediately if construction work temporarily or permanently ceases Deadline for completing stabilization must be established in permit Pollution Prevention Minimize stormwater exposure to construction materials, chemical products, wastes Prohibit discharges from pollution sources, such as fuels and oils from vehicle and equipment O&M

7 Changes to Construction & Development Stormwater Effluent Guidelines Summary of proposed changes to the existing rule: Addition of a definition of "infeasible." EPA is proposing this change because several of the rule requirements allow exceptions in cases where a particular practice is infeasible. Revisions to several of the non-numeric requirements. EPA is proposing several changes to the non-numeric requirements of the rule in order to provide clarity and allow additional flexibilities. Withdrawing the numeric turbidity effluent limitation and monitoring requirements. EPA had previously stayed the numeric turbidity limitation and monitoring requirements. EPA is proposing to withdraw these requirements and reserve these sections of the Code of Federal Regulations

8 Published in the Federal Register April 1 Comment period closed May 31 Final Rule Changes expected in late 2013 In general DEQ will be working with EPA to determine if updates are necessary. More Information - EPA s C&D Web Page

9 EPA s Stormwater Rulemaking Addressing Stormwater Runoff Volumes 0-10% 60% NEMO

10 Increased Run-off due to Impervious Surfaces Sidewalks Roads Driveways Parking Buildings Center for Watershed Protection

11 Effects of Higher Flow Volumes and Higher Flow Velocities Stream widening and erosion Decreased channel stability Reduced fish passage Loss of pool-riffle structure Lower summer base flows Loss of riparian tree canopy Temperature impacts Decreased substrate quality Embeddedness (fine sediments become embedded into the coarse substrate)

12 Excessive Runoff from Impervious Surfaces also Contributes to Localized Flooding and Basement Back-ups

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15 95 th Percentile Storm Target for Channel Protection

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19 Costs For Many New Developments, Not Necessarily Higher Costs Flexibility in site design and lot size Tailor to drainage, site characteristics Find optimal locations for BMPs Minimize impervious surfaces

20 Natural Topography includes two predominant drainage patterns Some valuable Green infrastructure on the site Bielinski Homes

21 Wetlands Preserved Bielinski Homes Natural Drainage Patterns Maintained

22 Bielinski Homes Integrating Low Impact Development concepts can result in a development that is LESS expensive!

23 EPA Stormwater Calculator Site Scale Runs off SWMM Rainfall and soils data pre-loaded Quantifies the effects (results) of incorporating BMPs on the site

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25 Schedule for Federal Stormwater Rulemaking Rulemaking initiated fall 2009 Data collection and outreach through mid 2013 Drafting of rule and cost estimates during Propose rule for comment 2013 Finalize rule late 2014

26 What Measures can be Implemented to Meet Performance Standards? Green Infrastructure Increase Infiltration Increase Evapotranspiration Harvest and Re-use Stormwater Reduce Volume of Runoff

27 Questions Bob Newport, NPDES Programs Branch, U.S. EPA Region 5 (Chicago Office) newport.bob@epa.gov Christe Alwin, MS4 Program Specialist, Lansing District Office, DEQ alwinc@michigan.gov