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Penn Township
Telephone: 717-632-7366                 20 Wayne Ave Hanover, PA 17331                            Fax: 717-632-2464
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Stormwater Management and MS4

What is Stormwater? 
Stormwater is the excess water from rain or snowmelt that the ground cannot soak up. In many parts of the Township, stormwater flows into a storm drain and then through the storm sewer system. This system of pipes and channels will eventually discharge the water into a local stream or lake. There is no treatment for stromwater - anything that goes into a stormdrain will go straight to our waterways, pollutants included.

Stormwater Management

Smart stormwater management plays a vital role in reducing flooding, protecting infrastructure, and keeping our streams and lakes clean. As new developments, roads, and industries have gone in, much of the land in the Township has been converted to impervious surfaces.  An impervious surface is something like a parking lot, building, or road that covers the ground surface and prevents water from soaking in. The more impervious surface you have, the more stormwater runoff you have.

Decades ago, development occurred without much note to how the impacts of stormwater should be mitigated. Today, we have stringent policies on how development can proceed so that the risks of flooding and environmental degradation are reduced as much as possible.


Federal, state, and local regulations oversee the management of stormwater. The Clean Water Act of 1972 (CWA) establishes a framework for regulating pollutants discharged into waterways and is administered by the US Environmental Protection Agency (EPA). The PA Department of Environmental Protection (DEP) has been delegated to oversee some of these federal regulations, as well as to enforce the PA Clean Streams Law of 1937. Additionally, Penn Township's Stormwater Ordinance of 2011 defines the specific regulations for our municipality.

MS4 Program

In 2016, Penn Township was notified of its designation as a small MS4. MS4 stands for Municipal Separate Storm Sewer System and refers to the Township's stormwater conveyance systems. The MS4 Program is a federal program that regulates stormwater in urbanized areas. Because the population density of Penn Township has surpassed a certain threshold, the impact of our stormwater on natural systems is high enough to require regulation under the MS4 Program.

The Township applied for its MS4 permit in 2017 and we are expecting to receive it sometime this year. As a permittee, we will be required to develop a Stormwater Management Program that incorporates the following six elements:

  • Public education and outreach
  • Public involvement and participation
  • Illicit discharge detection and elimination
  • Construction site runoff control
  • Post-construction stormwater management
  • Pollution prevention and good housekeeping
To learn more about stormwater and MS4 in Penn Township, use the links to the right and across the top of this page.​
Informative Links
For questions, comments, or concerns regarding stormwater, illicit discharges, or construction runoff, call
(717) 632- 7366 ext. 145 Monday through Friday 8:00-4:30, or ext. 124 outside of normal hours
How can you reduce pollution?
What is MS4?
There are currently vacancies on the Penn Township Storm Water Authority Board
If you are interested in serving, please fill out the application and submit it at the Municipal Building at 20 Wayne Avenue.