Improving water quality is an important issue in today’s construction industry.  The Environmental Protection Agency (EPA) has developed the National Pollutant Discharge Elimination System (NPDES) legislation in order to control storm water runoff.  Whether you are constructing a highway, developing a new commercial building site, or maintaining an industrial operation, this legislation effects you.  Phase II, which went into effect on March 10, 2003, requires all small municipal separate storm water sewer systems (MS4s) within urbanized areas to submit a General Permit application.  An urbanized area is defined as any MS4 that serves a population of at least 10,000 people with a population density of 1,000 people/square miles or any MS4 that contributes substantially to storm water pollutant loading.   Phase II also requires that Storm Water Pollution Prevention Plans (SWPPP) be completed for every construction site of greater than one (1) acre.

It is intended to further reduce adverse impacts to water quality and aquatic habitat by instituting the use of controls on the unregulated sources of storm water discharges that have the greatest likelihood of causing continued environmental degradation.  Phase II will reduce the impacts of storm water runoff through a strengthened, yet flexible and cost-effective, storm water program. 

Phase II requires municipal storm sewer systems serving populations under 100,000 that are located in urbanized areas to obtain a National Pollutant Discharge Elimination System (NPDES) permit under the Clean Water Act.  This will result in storm water controls for approximately 5,040 additional municipalities across the country.