Stormwater Management

Stormwater is broadly defined as water from rain or snow/ice melt that flows across the ground and paved surfaces. This stormwater may soak into the ground, or eventually make its way to local streams or sinkholes, impacting the quality of water for aquatic life, recreation, and drinking water supplies.

Maintaining clean water benefits people, animals, and aquatic life. Storm drains carry rainwater and pollutants directly to streams and rivers. Any pollutants have the potential to lower the water quality, affect fish health, and reduce the number of beneficial plants and insects.  Inadequate management of stormwater runoff can increase flood flows and velocities, erosion and sedimentation, and overwhelm the carrying capacity of streams.  Flooding increases the threat (and costs) to damage property, infrastructure, and negatively impacts public health.   

One of the most important aspects of a storm water system is the fact that it will drain into the ground or a stream, which ultimately becomes a source for drinking water. This is a primary reason why Pennsylvania has established strict guidelines which need to be followed when dealing with or working around storm sewers.


Please review the Lower Frederick Stormwater Ordinance (Chapter 134) for information related to any project that you may be considering:

The Code contains detailed information regarding the stormwater management requirements for projects in Lower Frederick Township.  Briefly, the following rules apply to stormwater management in Lower Frederick Township:

  • The code defines the need to address stormwater when a property owner adds more than 1,000 square feet of impervious surface.
  • The code defines the need to address stormwater when a property owner disturbs more than 5,000 square feet of area.
  • The code prohibits discharge of any nonstormwater, including sewage, process wastewater, and washwater.


The Stormwater Management Program has multiple components, and is regulated by the Pennsylvania Department of Environmental Protection (DEP) through the Municipal Separate Storm Sewer System (MS4) Program. Through this program, Lower Frederick Township is issued a National Pollutant Discharge Elimination System (NPDES) permit for stormwater discharges in the urbanized area.  The permit is issued for a 5-year period. The current permit is for the period from 2019 – 2023.  Lower Frederick Township has a Stormwater Management Program that has been implemented to address the conditions of the permit.

The following six Minimum Control Measures (MCMs) are required as part of the permit:

  1. Public Education and Outreach
  1. Public Involvement / Participation
  1. Illicit Discharge Detection and Elimination (IDD&E)
  1. Construction Site Stormwater Runoff Control
  1. Post Construction Stormwater Runoff for New Development
  1. Pollution Prevention and Good Housekeeping


Lower Frederick Township relies on the Montgomery County Conservation District (MCCD) as the authorized agency of DEP for administering Construction Site Stormwater Runoff Control for disturbance of more than one acre, and a portion of the Post Construction Stormwater Runoff for New Development.

Please see the links below for more information about stormwater management.