Phase II Federal Storm Water Rule

Phase II Storm Water Rule in the Rouge Watershed

The U.S. Environmental Protection Agency (USEPA) is implementing the Phase II Storm Water Regulations (see below), which requires approximately 170 Southeast Michigan municipalities to obtain a National Pollutant Discharge Elimination System (NPDES) permit to cover their storm water discharges. In the Rouge River Watershed, 46 out of the 48 communities are included within the regulation and will need to be permitted.

The Michigan Department of Environmental Quality (MDEQ) felt their Michigan General Storm Water Permit accomplished the same environmental objectives as the Phase II Storm Water Regulations. Therefore, MDEQ proposed to USEPA, under USEPA's Regulatory Innovation program, that the Michigan General Storm Water Permit be considered the equivalent to the Phase II Storm Water Regulations. USEPA approved the proposal and concluded that the Michigan General Storm Water Permit could be used in lieu of permits that would otherwise be required by the Phase II Regulations.

For additional information on the Michigan General Storm Water Permit, click here.

For additional information on the Phase II Regulations or to download the rule itself, click here.
USEPA Phase II Storm Water Rule Fact Sheets
Phase II Areas of Designation

Summary of USEPA's Storm Water Program
The following is a very brief summary of the USEPA Phase I and Phase II NPDES storm water program. This information is from the USEPA web site dealing with the Federal Storm Water Rule.

The 1972 Amendments to the Federal Water Pollution Control Act (commonly known as the Clean Water Act or CWA) prohibit the discharge of any pollutant to waters of the United States from a point source unless the discharge is authorized by a NPDES permit. The NPDES permitting program is designed to track point sources, monitor the discharge of pollutants from specific sources to surface waters, and require the implementation of the controls necessary to minimize the discharge of pollutants.

Initial efforts to improve water quality under the NPDES program primarily focused on reducing pollutants in industrial process wastewater and discharges from municipal sewage treatment plants. But as pollution control measures for these sources were implemented and refined, studies showed that more diffuse sources of water pollution were also significant causes of water quality impairment. Specifically, storm water runoff draining large surface areas, such as agricultural and urban land.

In 1987, the CWA was again amended by Congress to require implementation of a comprehensive national program for addressing problematic non-agricultural sources of storm water discharges. As required by the amended CWA, the NPDES Storm Water Program is being implemented in two phases:

Phase I Of the NPDES Storm Water Program
In response to the 1987 Amendments to the CWA, EPA developed Phase I of the NPDES Storm Water Program in 1990. Phase I requires NPDES permits for storm water discharges from:

• "Medium" and "large" municipal separate storm sewer systems (MS4s) generally serving, or located in incorporated places or counties with, populations of 100,000 or more people; and
• Eleven categories of industrial activity, one of which is construction activity that disturbs five acres or greater of land.

Permit coverage can be either under an individually tailored NPDES permit (used by MS4s and some industrial facilities) or a general NPDES permit (used by most industrial facilities and construction sites). Further information is available on the Phase I of the NPDES Storm Water Program web page.

Phase II of the NPDES Storm Water Program
The Storm Water Phase II Final Rule was signed on October 29, 1999 and published in the Federal Register on December 8, 1999. The Phase II Rule requires NPDES permit coverage - mostly under general permits - for storm water discharges from:

• Certain regulated small MS4s (primarily all those located in urbanized areas) and
• Construction activity disturbing between 1 and 5 acres of land

These new sources would be subject to similar yet distinct storm water management requirements than the sources covered under Phase I. In addition, the rule includes a revised version of the original Phase I industrial "no exposure" exclusion whereby facilities with no exposure of industrial activities or materials to storm water do not need to seek coverage under an NPDES Storm Water Permit. Further information is available on the Phase II of the NPDES Storm Water Program main web page.

Please address all comments and suggestions about the contents of this Web page to rougeweb@co.wayne.mi.us.

The Rouge River National Wet Weather Demonstration Project is funded, in part, by the United States Environmental Protection Agency (EPA) Grants #XP995743-01, -02, -03, -04, -05, -06, -08 and C-264000-01.