Lower Merion, PA Environmental Rules: Stormwater Management (2026)

Section 121-1 states the township's findings that inadequate stormwater management increases flooding, erosion, and sedimentation and burdens stream health, and sets the chapter's purpose of meeting water quality standards under 25 Pa. Code Chapter 93, preserving natural drainage, managing runoff near its source, maintaining groundwater recharge, and complying with the state's Act 167 stormwater studies. Section 121-2 makes compliance mandatory: no land may be used, no earth stripped or moved, and no structure built or extended without full compliance with the chapter, under authority the Pennsylvania Stormwater Management Act (Act 167 of 1978, as amended by Act 63 of 1984) grants the township.

Regulated activities include land development, subdivision, construction of new or additional impervious surfaces, construction of new buildings or additions, diversion or piping of a stream channel, installation of stormwater systems, and earthmoving. A regulated activity creating 1,500 square feet or less of additional impervious cover is exempt from peak-flow control, though the township can still require groundwater recharge or water quality compliance, and no waiver is available for stream diversion or stormwater system installation. Section 121-14 sets the permit fee under the township's Chapter A167 fee schedule, and Section 121-15 lets the Township Engineer attach conditions such as drainage structures, plantings, or easements before issuing a permit, with no permit issued until an approved runoff and erosion control plan is in place.

Permits under Section 121-16 expire if work has not started within six months or finished within one year, subject to an extension for unusual difficulties. Section 121-28 sets the penalty: a fine of not more than $1,000 for each offense, with each day a violation continues after notice from the Township Engineer a separate offense.