Lower Merion, PA Environmental Rules: Flood Zones (2026)

Zoning Code § 155-7.3 establishes the Floodplain Overlay District over any lot within the area subject to the base flood, as shown on the Township's Floodplain Overlay District Map and drawn from FEMA's Flood Insurance Study for Lower Merion Township, dated March 2, 2016. The overlay applies on top of every underlying zoning district and to all lots within it. Subsection D permits only a defined list of uses and no others: cultivated, forested, or grazing land; outdoor nurseries or orchards; wildlife sanctuaries; game farms without structures; forestry; required yard area; floodproofed sanitary and storm sewers and utility lines; certain recreational uses without enclosed structures; and a few narrow drainage and parking exceptions.

Subsection F then prohibits freestanding structures, buildings, retaining walls, and substantial improvements, including generators, mechanical equipment, and transformers, unless approved under § 155-7.3 as a variance, special exception, or conditional use. Certain uses, including sanitary landfills, junkyards, outdoor storage of vehicles and toxic chemicals, mobile home parks, hospitals, and jails, may never receive a variance under any circumstances (§ 155-7.3F(2)). Any modification of the mapped floodplain boundary requires a zoning permit from the Zoning Officer, Township Engineer review, and, in a special flood hazard area, prior FEMA approval (§ 155-7.3C). Section 155-7.3I makes the entire article take precedence over every other portion of the Township Code when there is a conflict.