UNH T2 Center Header

NPDES II Impacts More Municipalities

2000 Census Redefines MS4 Designations

The article on page 1 describes the NPDES II regulations. They will impact all New Hampshire municipalities. (See “NPDES II and Highway Garage Complexes” in this issue.) The greatest impact is on cities and towns with “Regulated Municipal Separate Storm Sewer Systems” (MS4s). An MS4 is a road drainage system owned by a government entity, such as a municipality. It includes all roads and streets, catch basins, curbs, gutters, ditches, culverts, man-made channels, and storm drains.

EPA designates MS4s located in “urbanized areas” (UAs) as defined by the Bureau of the Census. The 1990 Census UAs covered all of Dover, Manchester, Nashua, Portsmouth, Rochester, and Somersworth. They covered parts of

Amherst Auburn Bedford Durham Goffstown Hollis
Hooksett Hudson Litchfield Londonderry Madbury Merrimack
New Castle Newington Pelham Plaistow Rollinsford Rye
Salem Windham        

Redefinition of MS4s

Based on the 2000 Census EPA has expanded the designated areas in many of these towns. It has designated all of Atkinson and parts of the fol­lowing towns.

Brentwood Chester Danville Derry East Kingston Exeter
Greenland Hampstead Hampton Hampton Falls Kingston Lee
Milford Milton Newton North Hampton Sandown Seabrook

The specific area definitions are in Census Bureau maps. EPA Boston, who administers NPDES II in New Hampshire, will distribute them. When available, the UNH T² Center will inform the impacted towns through the PW.Net and NHLogin email listserves. (To join PW.Net email a request to t2.center@unh.edu.)

What is Required

Municipalities with a regulated MS4 must develop a Storm Water Management Program (SWMP). The deadline for initial application is March 10, 2003. SWMP must be implemented over the following 5 years.

The SWMP must cover the six “minimum control measures” described on Page 1. The EPA describes specific requirements in a separate Fact Sheet for each measure. (EPA websites below.)

Assistance to NH Municipalities

Various agencies can help the MS4 commu­nities. The EPA Boston office, in addition to pro­viding area definition maps, will have several out­reach events this fall.

The NH Office of State Planning can provide model ordinances, regulations, and guidance. NH Department of Environmental Services staff can help with illicit discharge detection. The NH Department of Transportation is a regulated MS4 within the designated UAs. They will coordinate their SWMPs with affected municipalities.

Many UNH T² Center workshops and news­letter articles provide information useful for NPDES II compliance actions. It is developing a Drainage Maintenance System, which will help municipalities prepare and execute NPDES II.

Private engineers and vendors can assist with engineering studies, equipment, and construction. Finally, municipal officials can assist each other. PWNet is one way to communicate with peers.

Sources:

Return to Summer 2002