Stormwater Management Ordinance

On November 28, 2023, Derry Township adopted a revised stormwater management ordinance (Chapter 174). These regulations require stormwater management facilities to be designed and installed on individual properties when impervious area in excess of the threshold established by the ordinance is proposed.

This ordinance may be applicable when new impervious area is added to your property. ย Impervious area is surface area that has been compacted or covered to the extent that it is highly resistant to infiltration by water. This includes compacted stone, paving, concrete, roof area, etc.

A project that adds more than 5% of the lotโ€™s total area in new impervious surfaces, or more than 1,000 square feet of new impervious area on lots 20,000 s.f. or greater, will be required to provide volume control documented on a plan and in a report. Projects exceeding 5,000 square feet of new impervious area will also be required to provide rate controls and an as-built survey plan of the improvements in addition to the volume control design plan and report.

Click here to view the Stormwater Management Ordinance (Ord. No. 2023-08) in its entirety.

Stormwater Management Site Plan and Report Submission Information/Forms

Other Documents