Philadelphia
Philadelphia Stormwater Management Guidance Manual
Document Metadata
“The City of Philadelphia is required, by a series of State and Federal regulations and mandates, to clean up its waterways.”
Introduction, Page 10
“Professional Engineer licensed in the Commonwealth of Pennsylvania”
Chapter 2, Page 23
“Version 3.4”
Cover Page
“Version 3.4 July 2026”
Cover Page
“Version 3.4 July 2026”
Cover Page
“The Philadelphia Stormwater Management Guidance Manual (the Manual, or SMGM) is a comprehensive resource for the development community in complying with the Philadelphia Water Department (PWD) Stormwater Regulations (Stormwater Regulations) and designing stormwater management on private property.”
Introduction, Page 1
Design Criteria
“Return period DURATION 1 yr 2 yr 5 yr 10 yr 25 yr 50 yr 100 yr”
Chapter 3, Page 100, Table 3.4-3
“The Water Quality requirement stipulates infiltration of the first 1.5 inches of runoff from all directly connected impervious areas (DCIA) within the limits of earth disturbance. This quantity of stormwater runoff is referred to as the Water Quality Volume (WQv).”
Chapter 1, Page 15
“The NRCS Curve Number Method is used to estimate site stormwater runoff from a given storm. ... The Rational Method may be used when designing storm sewers.”
Chapter 3, Page 98 & Page 95
No evidence cited
“This chapter consists of guidance and requirements for the following SMPs: Section 4.1 – Bioinfiltration/Bioretention Section 4.2 – Porous Surfaces Section 4.3 – Green Roofs Section 4.4 – Subsurface Infiltration Section 4.5 – Cisterns Section 4.6 – Blue Roofs Section 4.7 – Ponds and Wet Basins Section 4.8 – Subsurface Detention Section 4.9 – Media Filters Section 4.14 – Blue-Green Roofs Section 4.15 – Drainage Wells”
Chapter 4, Section 4.0.2, Page 2