Stormwater Management: Fairfax Countys MS4 Program

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Stormwater ManagementFairfax Countys MS4
Program

• SWANA Surface Water and Groundwater Training
• June 24, 2009

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What is an MS4?

• MS4 Municipal Separate Storm Sewer System
• Conveyance or system of conveyances
• Owned by a public entity
• Collects and conveys stormwater
• Discharges to waters of the U.S.
• Not a combined sewer
• Not part of a Publicly Owned Treatment Works
  (POTW)

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Fairfax Countys MS4

• 42,000 Storm Drainage Inlets and Catch Basins
• 3,000 Private Stormwater Management Facilities
• 1,300 Public Stormwater Management Facilities

• 1,300 Miles of Pipe
• 79 Miles of Manmade Channels
• 22 State Regulated Dam Sites

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MS4 Program Timeline

• 1972 Clean Water Act established the National
  Pollutant Discharge Elimination System (NPDES)
• 1975 NPDES delegated to Virginia
• Virginia Pollutant Discharge Elimination System
  (VPDES)
• 1987 MS4s added to NPDES
• 1990 Phase I NPDES developed
• Large and medium MS4s (more than 100,000
  residents)
• Industrial activities (11 categories regulated)
• 1999 Phase II NPDES program for small MS4s
• 2005 MS4 program transferred from DEQ (VPDES) to
  DCR Virginia Stormwater Management Program (VSMP)

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Fairfax County MS4 Permit History

• 1991 Application Part I submitted to DEQ
• 1992 Application Part II submitted to DEQ
• 1997 First 5-year VPDES permit issued
• 2001 Renewal application submitted to DEQ
• 2002 Second 5-year VPDES MS4 permit issued
• 2006 Renewal application submitted to DCR
• January 2007 Second permit expired but
  administratively continued by DCR
• January 2007, 2008, 2009 Pre-draft permits
  received from DCR

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MS4 Permit Overview

• Permit issued to Fairfax County
• Compliance coordinated by Stormwater Management
• Authorizes specific discharges from MS4 to waters
  of the U.S.
• Requires development and implementation of a
  Stormwater Management Program (SWMP) to
• Reduce the contamination of stormwater runoff
• Prohibit illicit discharges

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Current SWMP Components

• Watershed Management Program
• Structural and Source Controls
• Areas of New Development and Significant
  Redevelopment
• Roadways
• Retrofitting
• Pesticide, Herbicide, and Fertilizer Application
• Illicit Discharges and Improper Disposal
• Spill Prevention and Response
• Industrial and High Risk Runoff
• Construction Site Runoff
• Storm Sewer Infrastructure Management
• Public Education
• Monitoring Programs

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Current SWMP Components (Continued)

• Legal Authority
• Control contribution of pollutants to MS4
• Prohibit illicit discharges to MS4
• Control spills and dumping to MS4
• Require compliance with permit conditions
• Carry out inspections, surveillance and
  monitoring to determine compliance with permit
  conditions
• Stormwater Management Program Resources
• Shall provide adequate resources to implement
  SWMP to Maximum Extent Practicable (MEP)
• Stormwater Management Program Review and Updates
• Update SWMP annually
• Monitoring and Reporting Requirements

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MS4 Program Challenges

• Program Coordination
• Within DPWES Solid Waste
• Industrial and High Risk Runoff
• Public Education
• Within Fairfax County
• Outside of Fairfax County
• Infrastructure Age and Extent
• Aging Infrastructure Requires Maintenance
• Increased Number of Facilities as Move from
  Regional to Onsite Controls

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MS4 Program Challenges (Continued)

• Physically Interconnected Systems
• Local MS4 Permits
• Arlington and Loudoun Counties
• Cities of Alexandria, Fairfax and Falls Church
• Towns of Herndon and Vienna
• Fairfax County Public Schools
• State MS4 Permits
• George Mason University
• Northern Virginia Community College
• VDOT Northern Urban Area
• Federal MS4 Permits
• U.S. Central Intelligence Agency
• U.S. Army Fort Belvoir

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2009 Pre-Draft PermitSummary of Significant
Changes

• Permittee responsibilities extended beyond MEP
• and protect water quality by satisfying the
  appropriate water quality requirements of the
  CWA
• Discharge conditions vs. discharge goals
• Industrial and high risk runoff program expanded
  to include all municipal facilities
• Incorporation of impaired waters and TMDLs
• Review and update all ordinances and other legal
  authority
• Clear definition of roles and responsibilities

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Impaired Waters and TMDLs

• Federal and State law require
• Monitoring of water quality
• Assessment of monitoring data
• Identification of impaired waters (do not meet
  WQS)
• Development of Total Maximum Daily Load (TMDL)
  for impaired waters
• Identify pollutant sources
• Quantify reductions needed to meet WQS
• State law also requires development of a TMDL
  Implementation Plan (IP)

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2004 Impaired Waters
17 Streams 1 Reservoir 6 Tidal Embayments 24
Total Impaired Waters
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2006 Impaired Waters
36 Streams 1 Reservoir 15 Tidal Embayments 52
Total Impaired Waters
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2008 Impaired Waters
49 Streams 1 Reservoir 17 Tidal Embayments 67
Total Impaired Waters
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TMDL Allocations To Date

• Bacteria WLA Reduction
• Upper Accotink Creek 0.13 E15 cfu/yr 92
• Lower Accotink Creek 1.73 E12 cfu/yr 97
• Bull Run 7.61 E10 cfu/yr 89
• Difficult Run 9.44 E12 cfu/yr 90
• Four Mile Run 2.04 E13 cfu/yr 98
• Popes Head Creek 6.83 E11 cfu/yr 94
• Sediment
• Bull Run 4,096 tons/yr 78
• Difficult Run 3,595 tons/yr 32
• Popes Head Creek 1,571 tons/yr 28
• PCBs
• Tidal Potomac 54.7 g/yr 75

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Tools for Compliance

• Monitoring Programs
• 2001 Stream Protection Strategy Baseline Study
• 2002 Stream Physical Assessment
• Ongoing Programs
• Bacteria and Water Chemistry
• Benthic Macroinvertebrates
• Fish Community
• GIS and Data Management
• Watershed Management Planning
• Improved Regional Coordination

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Fairfax County Stream Conditions
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Questions?
Kate Bennett, Ecologist III Stormwater Planning
Division Phone [phone] E-mail
kate.bennett_at_fairfaxcounty.gov