National Pollution Discharge Elimination System (NPDES) Program
What is the National Pollution Discharge Elimination System? The National Pollution Discharge Elimination System (NPDES) was created by the Clean Water Act to control water pollution from agriculture, commercial and industrial facilities, municipalities, wastewater treatment plants and construction sites.  The City of Rockville is designated as a Phase II Small Municipal Separate Storm Sewer System (MS4) community, meaning that we have a population of less than 100,000 people (small) and we have a municipal separate storm sewer system (MS4 - as opposed to a combined sewer system, where both sanitary waste and stormwater flow to a treatment plant through the same pipes).  NPDES requirements for municipalities followed a phased approach, with medium and large communities (such as Montgomery County) starting first during Phase I, and small communities (such as Rockville) starting a few years later during Phase II.  The City of Rockville's NPDES Permit In Maryland, the NPDES permit program is administered by the Maryland Department of the Environment (MDE).  Rockville is covered under MDE's "General Discharge Permit No. 03-IM-5500  General NPDES Permit No. MDR05500" which first took effect April 14, 2003.  It is a five-year permit requiring re-authorization at the end of the five years (April 14, 2008).  Our NPDES permit, sometimes just called our “stormwater permit”, enables the City to discharge stormwater runoff and the associated non-point source pollution to local streams.  This permit has several program requirements in the following six areas: Public Education on Stormwater Impacts Public Involvement and Participation Illicit Discharge Detection and Elimination Construction Site Stormwater Runoff Control Post Construction Stormwater Management Pollution Prevention and Good Housekeeping for Municipal Operations Each year the City submits an annual report to MDE detailing our compliance with specific programs within each of the six areas.