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Rhode Island Department of Transportation Settlement

Overview of Storm Sewer Authority

The Rhode Island Department of Transportation (RIDOT) operates a Phase II municipal separate storm sewer system (MS4) that serves RIDOT roadways and facilities across the State of Rhode Island.  The RIDOT MS4 is an expansive system, with more than 25,000 catch basins and 3,800 outfalls that extend over 3,300 lane miles, approximately one-third of which are divided highways, the rest are rural and urban surface roads; about one-half of the system is within the MS4 Permit Area.  RIDOT is authorized under a National Pollutant Discharge Elimination System (NPDES) general permit to discharge stormwater to waters of the United States through its MS4 provided it complies with all provisions of the permit.

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The City failed to develop and implement a stormwater pollution prevention and management program that minimizes the discharge of pollutants to the maximum extent practicable in violation of Section 402 of the Clean Water Act and the terms and conditions of its NPDES permit. Specific deficiencies include failure to:

  • address in its Storm Water Management Program Plan (“SWMPP”), and failure to implement, requirements of applicable EPA-approved total maximum daily load (“TMDL”) determinations;
  • submit and implement required scope of work documents that describe the process and rationale that will be used to select best management practices and measureable goals to ensure that applicable TMDL provisions will be met;
  • implement storm water controls necessary to control the discharge of pollutants of concern to water-quality impaired waters to the maximum extent practicable;
  • fully develop, implement and enforce a program to detect and eliminate illicit discharges to the RIDOT MS4;
  • conduct spring dry weather illicit discharge detection and elimination screening at MS4 outfalls;
  • conduct adequate street sweeping and inspection/cleaning of catch basins on an annual basis; and
  • inspect, clean, and repair catch basins and other elements of RIDOT’s storm drainage system.

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Injunctive Relief

The consent decree requires the RIDOT to improve its stormwater management program including to:

  • comply with applicable TMDL requirements, including building structural controls where appropriate;
  • reduce its discharges of pollutants of concern to impaired waters to the maximum extent practicable, including implementing structural and non-structural controls
  • implement an effective illicit discharge detection and elimination program and prevent unauthorized discharges,
  • comply with street sweeping and catch basin permit requirements, and
  • inspect, clean and repair, as necessary, catch basins and other components of its storm drainage system.

The Consent Decree includes the following Next Generation Compliance tools:

  • RIDOT must consider and evaluate the use of green infrastructure for controlling discharges from its MS4 to impaired waters;
  • RIDOT must post certain submissions required under the consent decree on its website; and
  • RIDOT must submit reports and deliverables under the consent decree in electronic format.

EPA estimates that in total RIDOT will spend approximately $200 million over a 20 year period to implement the required injunctive relief.

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Environmental Justice

Significant portions of the areas of Rhode Island impacted by this case are environmental justice (“EJ”) areas.  The actions required by the consent decree will have multiple positive impacts on Rhode Island EJ areas.  The consent decree places an emphasis on EJ areas in illicit discharge investigations and removals.

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Health and Environmental Effects

Polluted stormwater runoff is commonly transported through MS4s and ultimately discharged untreated into local rivers, lakes and streams. Roads and highways discharge metals, phosphorous, nitrogen, sediment and suspended particles, grease, and salt.  Urban roadways also discharge trash and significant amounts of bacteria.  Illicit discharges can enter the MS4 through direct connections (e.g., wastewater piping either mistakenly or deliberately connected to the MS4) or indirect connections (e.g., infiltration into the MS4, spills collected by storm drains, or paint or used oil dumped directly into a storm drain). The result is untreated discharges that contribute high levels of pollutants, including heavy metals, toxics, oil and grease, solvents, nutrients, viruses, and bacteria to receiving waters.

When discharged into nearby waterways through MS4s, these pollutants can degrade water quality, thereby discouraging recreational uses, contaminating drinking water supplies, and adversely impacting fish, other aquatic life and wildlife. In addition, an increase in the amount of impervious surfaces (e.g., parking lots, driveways, and rooftops) resulting from new development can impact waterbodies by increasing the quantity and velocity of water delivered to the waterbodies during storms. This can result in streambank scouring and erosion and downstream flooding which can harm aquatic life and damage property.

The stormwater NPDES permit program requires municipalities to develop and implement a stormwater management program that is intended to improve the quality of local waterways by reducing the impact of new development and reducing the amount of pollutants that stormwater runoff and melting snow pick up and carry into storm sewer systems.

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Civil Penalty

RIDOT will pay a civil penalty of $315,000 and preserve two properties as a supplemental environmental project.  The parcels will be preserved in their natural state in perpetuity, providing environmental protection to a portion of the watersheds in Johnston and Lincoln, Rhode Island.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the District of Rhode Island, is subject to a 30-day public comment period and final court approval. Information on submitting comment is available at the Department of Justice website.

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For more information, contact:

Susan D. Bruce 
Water Enforcement Division
U. S. Environmental Protection Agency
1200 Pennsylvania Ave, NW (MC 2243A)
Washington, DC 20460 
(202) 564-8329

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