Bethlehem, PA Environmental Rules: Stormwater Management (2026)

S. 1) and the Municipalities Planning Code, requires a Drainage Plan for any Regulated Activity: land development, subdivision, construction of new impervious surfaces such as driveways and parking lots, earth moving, diversion of a stream channel, or installation of stormwater systems. 06 exempts a Regulated Activity that creates 10,000 square feet or less of additional impervious cover from Drainage Plan preparation, but the exemption is cumulative: once a parent tract's total added impervious cover since the original 1988 Act 167 ordinance exceeds 10,000 square feet, the full amount must meet the Ordinance's provisions.

Any project that instead qualifies for the small-disturbance exemption must still control water quality with a BMP such as a vegetated sheet-flow buffer at least as long as the impervious area it drains, disconnected roof downspouts routed over lawn or woodland to avoid gully erosion, or infiltration meeting the Ordinance's design standards. 05J) get no exemption under any circumstance. Agricultural plowing, agricultural operations and forest or timber management are exempt from rate-control and Drainage Plan requirements only if performed to the standards of 25 Pa.

Code Chapter 102, and the City may still deny or revoke any exemption at any time if it believes the project threatens public health, safety, property or the environment. A prior Drainage Plan approved as part of a subdivision or land development proposal before this Ordinance's effective date stays exempt from the water-quantity provisions unless the design is significantly revised, in which case a new Drainage Plan under the current Ordinance is required.