Did you know a 500 square foot roof produces 300 gallons of storm water runoff during a one inch rain storm? And flooding is Pennsylvania’s number one natural disaster. Too much or too little rain can cause problems which are best mitigated through what is known as “Storm Water Management.” In the past Storm Water Management was directing runoff to drains and culverts. However we know now that this pollutes water sources, washes away soils, causes drought, reduces water tables, and disrupts the water cycle. Now, Storm Water Management is about helping rain and water infiltrate into the property owner’s ground, flow naturally, and avoid “peak flows” that wash things away and flood otherwise dry places after storm events. Today’s Storm Water Management provides groundwater recharge for streams, lakes, and water supplies (your well, for example) and protects and maintains surface water quality. Any development (building a new structure, for example) has an effect on storm water runoff so Franklin Township has ordinances to minimize its harms and maximize its benefits. These ordinances require Storm Water Management Plans for non-exempt new buildings or for new impervious surfaces. Franklin Township requires a new driveway permit if a resident is paving or repaving a driveway on a township road because it can affect the way water runs.
All residents can help reduce storm water runoff and its damage. Minimizing grading; avoiding disturbing vegetated areas and stream banks; protecting natural flow water pathways; clustering uses and surfaces that are impervious to water; protecting steep slopes, floodplains, wetlands, and woodlands all reduce runoff volume and improve water quality and groundwater recharge.
You can also minimize or eliminate pesticide and fertilizer use; avoid compacting soil; use native plants in your landscaping; construct vegetated swales; capture runoff and reuse it (rain barrels); and plant lowered plant beds instead of raised plant beds.
See this pamphlet, “The Homeowner’s Guide to Stormwater” or this Penn State Extension webinar for more information and specific things you can do to handle storm water on your property.