April 20, 2009

U.S. EPA Issues Precedent-Setting Stormwater Decision

Posted on April 20, 2009 by David Van Slyke

On December 5, 2008, the U.S. EPA Region 1 announced that it would use its “residual designation authority” under Clean Water Act Section 402(p)(2)(3) to regulate owners of properties that discharge storm water into a three square mile urban watershed located within a major commercial center near downtown Portland, Maine. Landowners with one acre or more of existing “impervious surface” in the Long Creek watershed, such as parking lots, roads, and rooftops, will be required to obtain storm water permits under the National Pollutant Discharge Elimination System (NPDES).  The EPA decision was prompted by a March 6, 2008 petition from Conservation Law Foundation (CLF) asserting that certain storm water dischargers be required to obtain NPDES permits.  

The Long Creek Decision Reflects a Major Shift in EPA policy

The Long Creek decision, which closely follows a related decision announced by EPA Region 1 regarding the Charles River watershed in Massachusetts , represents a major shift in EPA policy.  For the first time, EPA is regulating runoff from parking lots and other impervious cover at existing commercial development (such as big box stores). EPA agreed with CLF that the percentage of impervious cover relates directly to storm water watershed degradation and that land development and associated impervious surfaces are a major source of water quality issues in impaired waterbodies such as the Long Creek and Charles River watersheds.

How will this change affect watershed landowners?

Under the program delegated to the Maine, DEP will now be regulating and issuing stormwater permits to all Long Creek watershed landowners meeting the one acre impervious cover threshold.  While storm water from new construction has been regulated by DEP under its existing stormwater rules, EPA’s Long Creek decision means that for the first time, Maine will impose stormwater permitting requirements for impervious cover on previously unregulated existing development.   

What are the requirements for watershed permittees?

EPA solicited public comment on its Long Creek RDA decision via a December 31, 2008 Federal Register Notice. The public comment period closed February 17, 2009; two public comments were recorded. Finalization of the decision is not expected until at least July 2009.

The precise scope of the requirements for prospective permittees will not be known until Maine DEP finishes its rulemaking; a draft rule regarding the new program will not be released until EPA issues its final decision.  However, it can be anticipated that landowners will have to control and treat storm water runoff from their parking lots, roads and roofs, develop and maintain various structural improvements and retrofits, monitor watershed conditions, and use best management practices at their properties.

Tags: Water


Permalink | Comments (0)