MS4 – Storm Water Management

Polluted storm water runoff is commonly transported through Municipal Separate Storm Sewer Systems (MS4s), from which it is often discharged untreated into local water bodies. To prevent harmful pollutants from being washed or dumped into an MS4, operators must obtain a NPDES permit and develop a storm water management program.


When our pets leave those little surprises, rain washes all that pet waste and bacteria into our storm drains. Then it pollutes our waterways. So what to do? Simple, dispose of it properly (preferably in the toilet.) Then that little surprise gets treated like it should.

You fertilize your lawn. Then it rains. The rain washes the fertilizer along the curb, into the storm drain, and directly into our lakes and streams. This causes algae to grow, which uses up oxygen that fish need to survive. So if you fertilize, please follow directions and use sparingly.

All the soap, scum, and oily grit runs along the curb. Then into the storm drain and directly into our lakes and streams. So how do you avoid this whole mess? Easy. Wash your car on grass or gravel instead of the street. Or better yet, take it to a car wash where the water gets treated and recycled.

Leaking oil goes from car to street, and is washed from the street into our storm drain and into our lakes and streams. Now imagine the number of cars in the area and you can imagine the amount of oil that finds its way from leaky gaskets into our water. So please, fix your oil leak.


If you have questions regarding storm water, please contact Hopewell Township or Pennsylvania Department of Environmental Protection’s Regional Office. For general questions, you may also contact DEP’s Bureau of Water management at 717-772-5661 or visit Thanks to the Washington State Water Quality Consortium for permission to adapt and use these posters.

Oils, paints and pet waste are not permitted in sewers. You are urged to report violations to Hopewell Township at 724-378-1460.

Hopewell Township Resident Complaint Form


Alternatives to Toxic Substances
Landscaping and Lawn Care
Pest Control
Pet Waste Management
Proper Disposal of Household Hazardous Wastes
Residential Car Washing

Introduction to MS4
The Homeowners Guide to Stormwater
Public Education & Outreach – Small MS4 Program: Minimal Control Measure #1
Public Participation & Involvement – Small MS4 Program: Minimal Control Measure #2
Illicit Discharge Detection & Elimination – Small MS4 Program: Minimal Control Measure #3
Construction Site Runoff Control – Small MS4 Program: Minimal Control Measure #4
Post-Construction Runoff Control – Small MS4 Program: Minimal Control Measure #5
Pollution Prevention/Good Housekeeping – Small MS4 Program: Minimal Control Measure #6

Rain-Drain Educational brochure
After the Storm flyer
Construction Runoff flyer

Clean Water Campaign Activity Book
Splish-Splash Activity Book

EPA’s Stormwater Management website:
DEP’s MS4 website: