AASHTO Subcommittee on Design

Transcription

1 Stormwater Regulations and Transportation: The Maine Department of Transportation Experience AASHTO Subcommittee on Design Annual Meeting - Portland, Maine June 12, 2012 Stephen W. Tibbetts, PE Senior Environmental Engineer Environmental Division Maine Department of Transportation 1

2 Maine Department of Transportation Some Facts Highway Network 22,750 miles of public road 8,368 miles state owned 13,930 miles town ways 452 miles other (Maine Turnpike,reservation, parks, etc) 1,737 miles of unbuilt roadway 1,854 miles of seasonally posted roads Maine DOT is responsible for 37% of the public road network, and 78% of all travel in Maine occurs on these roads. 27,459 cross culverts 28,400 entrance culverts Bridge Assets Structures: 1,962 bridges (> 20 ) 775 minor spans (> 10 and < 20 ) Passenger Transportation 6 commercial airports 30 general aviation airports 18 fixed route transit systems 42 miles of active passenger rail service (Amtrak Downeaster) 7 State of Maine owned ferry vessels 2,000 park-and-ride spaces (some shared ownership with MTA) 1 intermodal passenger facility 1 Commuter/Intercity Rail System Freight Transportation 3 major cargo ports 1,200 miles of active rail line 300 miles of State of Maine owned rail line 3 major freight carrying airports 2

3 NPDES Phase I NPDES Phase II The Regulations EPA Clean Water Act Amendment MS4 > 100k pop. CGP > 5 acres MSGP as is MS4 < 100k pop. CGP > 1 acre MSGP as is H 2 O Quantity MaineDEP Site Location Law Ch500 Stormwater Management Law Lakes Protection MEPDES CGP MS4 MSGP 1998 MOA 2003 MOA H 2 O Quantity RDA Petitions & Quality NPDES = National Pollutant Discharge Elimination System MEPDES = Maine Pollutant Discharge Elimination System MS4 = Municipal Separate Stormwater Sewer System CGP = Construction General Permit MSGP = Multi-Sector General Permit GP/IP = General Permit/Individual Permit Long Creek GP/IP 2007 MOA 3

4 The Regulations 2006 H 2 O Quantity & Quality 2007 RDA Petitions Long Creek GP/IP NATIONAL PARADIGM SHIFT Change in Focus for Stormwater Management 2012 Old Priority Flooding New Priorities Water Quality/Pollution & Removal Stream Channel Protection Flooding Thermal Impacts 4

5 How It All Applies to MaineDOT Construction Phase - Performance Standards CGP/Chapter 500 Stormwater Management MaineDOT Implemented through MOA with DEP Original signed in 1998, revised in 2003 and again in 2007 to reflect revisions to Ch500. Result of a long-term cooperative and positive relationship with Maine DEP! Includes Maine Turnpike Authority (MTA) No individual project permits required Annual report to MaineDEP summarizing project activity for the year. Basic Standards Erosion and Sedimentation Control: Applies to ALL projects: Special Provision 656 Soil Erosion and Water Pollution Control Plan (SEWPCP) Maine DOT ESC BMP Manual 5

6 Post-Construction Phase Permanent Stormwater Best Management Practices Chapter 500 General Standards Linear and Non-Linear Projects that trigger thresholds must meet water quality standard: Treat 1 of runoff from impervious Treat.4 of runoff from developed 75% for linear projects 95% for non-linear projects Most existing alignments are exempt except in UIS or Lakes Most At Risk Watersheds. New alignments and all Non-Linear Projects have to meet General Standards. Flooding standard (detention) may apply to some projects. 3 ac or more of impervious area 20 acres or more of developed area. Discharge to the ocean, a great pond, or a major river segment is an exemption. MaineDOT uses MaineDEP Stormwater BMP Manual for design standards, tweaking as req d. MaineDOT screening flow chart 6

7 Construction Phase - Performance Standards (Continued) Municipal Separate Storm Sewer System (MS4) permit 28 Phase II MS4 Communities MCM4 Chapter 500 Basic Standards Clusters, heavily developed No room for retrofits MEP standards apply (Maximum Extent Practicable) New development Redevelopment Post-construction O&M Long-term maintenance Inspections 7

8 Post-Construction Phase Permanent Stormwater Best Management Practices MS4-MCM5 Greater than 1 acre of disturbance from new development or redevelopment Treat to MEP Meet with DEP staff to come up with MEP treatment. Only applies in 28 communities in Maine. Long Creek General Permit RDA Long Creek Watershed Management District MaineDOT is a Participating Landowner MaineDOT pays annual fee to District - $3000/acre of impervious. MaineDOT has 65 acres of impervious. Stormwater BMPs are constructed by the District out of the annual fees. If MaineDOT constructs BMPs on their own, then we get an annual fee reduction based on the impervious area treated. 8

9 What s Next? Recent events Paradigm Shift Water quality Water quantity TMDL Statewide vs. Watershed only Non-specific pollutants Impervious Cover (IC) Residual Designation Authority (RDA) Long Creek MPDES GP Retrofitting/permitting for built environment On the Horizon EPA s National Rulemaking Initiative Expand stormwater program Include transportation standards Definitions in rulemaking Redevelopment MEP Administered Measurable Progress Balancing Priorities Restoration of UIS watersheds Protection of healthy watershed Reducing effective IC Feasibility limited to 6-24% Burden = demonstrate progress to avoid additional RDA 9

10 Questions? Maine DOT Environmental Office: 10