Stormwater three

Municipal stormwater: Small Municipal Separated Storm Sewer Systems (MS4) - Phase II

By March 2003, all communities within urbanized areas with a population of 50,000 or more and at least 1000 people per square mile were required to submit applications for stormwater permits. This has been called “Phase II” of the stormwater program. These urbanized areas were defined by the 2000 census. States are also supposed to evaluate whether urbanized areas with a population between 10,000 and 50,000 need to be covered by stormwater NPDES permits.

Some communities have sought individual permits, but most are covered by a state general permit. Communities with a population less than 10,000 can be required to obtain a permit if the agency determines it is necessary to do so to protect receiving waters from stormwater pollution. In addition to municipalities, MS4s include all public hospitals, schools, universities and other districts that maintain a stormwater system within an urbanized area.

The Phase II requirements are characterized by “six minimum measures” (40CFR122.34). All entities regulated under Phase II must develop a plan and programs to address the following:

• Public education and outreach on storm water impacts
  Small MS4s are required to develop and disseminate education materials that will raise the public awareness about what stormwater pollution is, what the causes are, and how individual responsibility can reduce it.

• Public participation and involvement
  Small MS4s are required to establish meaningful opportunities for the public to be involved in the development and implementation of the stormwater management plan that addresses where they live and work.

• Illicit discharge detection and elimination
  Some stormwater pollution problems are caused by non-stormwater discharges into the storm drain system. All permittees must immediately establish a program for identifying illicit discharges and taking steps to eliminate them.

• Construction site storm water runoff control
  Within the urbanized area, a program to reduce pollutants from any land disturbance one acre or greater (or if part of a one acre or greater common plan) must be developed, implemented and enforced by the permittee. This means that in addition to getting a permit from the state (or NPDES authority), the operator of the construction site must also comply with ordinance(s) developed at the municipal, county or district level that dictate how the activity can occur. This is intended to give municipalities regulatory control over these significant contributions to stormwater pollution in the urbanized area.

• Post-construction storm water management in new development and redevelopment
  Attention to post-construction controls and maintenance is generally NOT addressed in the permit program for construction sites. Small MS4s must develop a plan and ordinances to address the post-construction pollution problems on every construction site within the jurisdiction that is one acre or greater (or part of a one acre or greater common plan).

• Pollution prevention/good housekeeping for municipal operations
  All small MS4s must develop a plan and a program to manage their regular duties in ways that prevent future contributions of stormwater pollution into the system. Examples might include developing policies about hazardous waste management at city maintenance facilities, pesticide and fertilizer use in city parks, establishing green roofs on municipal buildings, and proper stormwater management at municipal construction sites.

These requirements are essentially included in the expectations for the large and medium-sized (Phase I) communities as well, but they are not spelled out this clearly. Notable differences between the Phase I and II requirements include that the Phase I communities must address industrial sources of stormwater pollution within their stormwater service area and generally that greater inspection and monitoring is required.

Communities working together

In some states, neighboring jurisdictions are working together and may apply to be co-permittees in order to achieve the six minimum measures. It can be particularly advantageous when the communities within a watershed are all working together. (See this lesson's Local Story for a great example.)

Stormwater utilities may be set up based on political or watershed boundaries and assigned responsibility for meeting the six minimum measures within that service area. If individual communities within the utility boundary are not co-permittees, agreements should be set up with the stormwater utility to establish responsibilities for meeting the permit requirements.