What is Stormwater?
Stormwater is any water that originates from precipitation or snowmelt. In areas where the landscape has been changed by development, this water may not be able to flow or infiltrate as it once did. Instead, it runs off into nearby surface waters, collecting pollutants on its way or pools on the surface. While storm sewers often collect runoff and some is treated, rain events may directly discharge into surface water without treatment. The three main impacts of stormwater are impairing water quality, decreasing groundwater recharge, and flooding.

Risks from Stormwater
As more development occurs, we have more and more impervious surfaces (surfaces water cannot easily penetrate)—such as roads and parking lots. These surfaces prevent infiltration (water naturally soaking into the ground). This causes the water to flow across the land into local waterways. The increase in stormwater runoff will increase localized flooding and damage even in small storm events. More stormwater runoff means less groundwater recharge and less natural pollutant removal.

Stormwater collects contaminants as it washes across roads, farm fields, roofs, and other impervious surfaces. When it drains into surface waters, it transports these pollutants into the water as well. Thus, we can consider stormwater a potential source of contamination to public drinking water supplies. It can pose a major risk to humans and impacts wildlife in and on the water bodies, it flows to.

Stormwater Regulations
Regulations across Pennsylvania require the management of stormwater to help protect our water sources, aquatic life, and wildlife by keeping contaminants out of the water. Act 167 and in some cases, NPDES permits for Municipal Separate Storm Sewer System (MS4) are regulated by the PA DEP. Understanding what regulations apply and how to meet the permit obligations can be difficult. To assist in this, PRWA has developed a program to assist in managing stormwater and complying with permit requirements. This includes:

• NPDES and Act 167 Compliance
• Stormwater Authority Formation Guidance
• Post-Construction Inspection and Training
• Funding & Technical Partners

To request onsite technical assistance please call us at (800) 653-7792, or email and a dedicated team member will contact you.