*** PWD Development Services Announces Updates to Stormwater Regulations ***

Greetings, Philadelphia Development Community!

Important news today from Development Services: Updates are proposed to PWD’s Stormwater Regulations and the Stormwater Management Guidance Manual. Please read on for more information.

Updates to PWD’s Stormwater Regulations Proposed for July 1, 2026

Beginning this July, the Philadelphia Water Department proposes to:

  • Exempt Small Residential Development from Post-Construction Stormwater Management requirements. Small Residential Development is a project that proposes less than 1-acre earth disturbance, consisting of buildings used exclusively as one- or two-family dwellings.
  • Expand Public Health and Safety (PHS) Release Rate areas. Projects in a PHS Release Rate area must comply with the set maximum release rate for the one-year through 10-year storm events.
  • Require approval of Erosion and Sediment (E&S) Control Plans for projects proposing earth disturbances of 5,000 SF and greater.

Stormwater Management Guidance Manual version 3.4 debuts July 1, 2026

Accompanying the proposed July 1 changes to Philadelphia’s Stormwater Regulations, Development Services will release the latest iteration of the Stormwater Management Guidance Manual, version 3.4. Notable updates include:

  • A new map illustrating the expanded Public Health and Safety (PHS) Release Rate areas (link)
  • The reclassification of Porous Pavements to Porous Surfaces
    • Porous Asphalt, Porous Concrete, and Resin-bound Aggregate will be removed from the Manual
    • Permeable Pavers, Reinforced Turf, Artificial Turf, and Porous Play/Safety Surface will remain, under the category of “Porous Surfaces”
  • Other SMP design modifications to improve SMP access, maintenance, and longevity

These newly added SMPs, as well as the reclassification of acceptable Porous Surfaces, are reflected in PWD’s revised “SMP Hierarchy” below.

PWD’s revised SMP Hiearchy (effective 07.01.2026)

Over the coming weeks, Development Services will provide additional information concerning these changes. In the meantime, readers are invited to sign up for our May 19 webinar; see details below.

PWD Stormwater Regulations Updates Webinar: Tuesday, May 19 at 10 AM

To introduce these proposed changes to PWD’s Stormwater Regulations and related Guidance Manual updates, on May 19 Development Services will host a Zoom webinar expressly for the development community and design professionals. Interested parties may register for this virtual presentation via this link.