As an incentive for an applicant proposing green stormwater strategies for stormwater management, the Philadelphia Water Department (PWD) offers two Expedited Post‑Construction Stormwater Management Plan (PCSMP) Reviews:
- Disconnection Green Review – Section 2.4.1
- Surface Green Review – Section 2.4.2
This Section assists the applicant in determining whether a project qualifies for an Expedited PSCMP Review, elaborates on the modified submission requirements (Section 2.4.3), and provides a list of benefits included in the process.
Only projects in the Development Compliance Review Path can qualify for Expedited PCSMP Review. If eligible, the applicant must identify the project as a candidate for either the Disconnection Green Review or the Surface Green Review when submitting the Existing Resources and Site Analysis (ERSA) Application (Section 2.1).
Chapter 3 provides detailed guidance on stormwater management approaches, which the applicant can use as a guide to determine which strategies are appropriate for their site and whether the project may qualify for an Expedited PCSMP Review. Under an Expedited PCSMP Review, the PSCMP Review Phase differs from projects that take a more traditional approach to stormwater management. These differences are discussed in the following Sections.
2.4.1 Disconnection Green Review
Only Redevelopment projects that are exempt from the Channel Protection and Flood Control requirements as defined in Section 1.2.1 are eligible for a Disconnection Green Review, and they must disconnect 95% or more of the post-construction impervious area within the project’s limits of disturbance (LOD). Projects eligible for a Disconnection Green Review only use disconnected impervious cover (DIC) to comply with Post‑Construction Stormwater Management (PCSM) Requirements (Section 1.2.1). Examples of projects that are most likely to benefit from this approach include trail and park projects, as well as residential and industrial projects where significant green roofs, permeable pavers, and/or reinforced turf are proposed.
Disconnections eligible for use in Disconnection Green Reviews include:
- Green roofs (Section 3.1.5 and Section 4.3);
- Permeable pavers (Section 3.1.5 and Section 4.2);
- Reinforced turf (Section 3.1.5 and Section 4.2);
- Porous play safe surfaces (Section 3.1.5 and Section 4.2);
- DIC artificial turf athletic fields (Section 3.5.5 details their important distinction from artificial turf athletic fields atop subsurface SMPs to manage directly connected impervious area (DCIA));
- Existing and proposed tree credits (Section 3.1.5);
- Pavement disconnections (Section 3.1.5); and
- Rooftop disconnections (Section 3.1.5).
The applicant must identify the project’s intent to qualify for a Disconnection Green Review when submitting the ERSA Application (Section 2.1) and will be notified by PWD of the project’s eligibility.
Projects qualifying for the Disconnection Green Review benefit from the following:
- Shorter (five-day) review during the PCSMP Review Phase;
- Exemption from the infiltration testing requirements (Section 3.3); and
- Use of PWD Standard Details for green roofs and porous pavements.
If additional stormwater management practices (SMPs) are needed to comply with National Pollutant Discharge Elimination System (NPDES) Permit requirements from the Pennsylvania Department of Environmental Protection (PA DEP), contact PWD to discuss Disconnection Green Review eligibility.
2.4.2 Surface Green Review
New Development and Redevelopment projects that can demonstrate that 100% of post-construction impervious area within the project’s LOD is managed by DIC and/or bioinfiltration/bioretention basins to comply with PCSM Requirements (Section 1.2.1) are eligible for Surface Green Review.
Eligible SMPs and disconnections consist of:
- Bioinfiltration/bioretention basins (Section 4.1);
- Green roofs (Section 3.1.5 and Section 4.3);
- Permeable pavers (Section 3.1.5 and Section 4.2);
- Reinforced turf (Section 3.1.5 and Section 4.2);
- DIC artificial turf athletic fields (Section 3.5.5 details their important distinction from artificial turf athletic fields atop subsurface SMPs to manage DCIA);
- Existing and proposed tree credits (Section 3.1.5);
- Pavement disconnections (Section 3.1.5); and
- Rooftop disconnections (Section 3.1.5).
The applicant must identify the project’s intent to qualify for a Surface Green Review when submitting the ERSA Application (Section 2.1) and will be notified by PWD of the project’s eligibility.
Projects qualifying for a Surface Green Review benefit from the following:
- Shorter (five-day) review during the PCSMP Review Phase;
- An option to delay infiltration testing until construction to provide flexibility and potential cost savings. This only applies to projects using bioinfiltration/bioretention basins meeting the minimum requirements set forth in the Bioinfiltration/Bioretention Basin Standard Detail in conjunction with the Bioinfiltration/Bioretention Basin Sizing Table (Table 4.1‑4), both found in Section 4.1.3; and
- Use of PWD Standard Details for bioinfiltration/bioretention basins, green roofs, and porous pavement.
Projects that qualify for a Surface Green Review must still meet all applicable PCSM Requirements, which may include the Channel Protection, Flood Control, and Public Health and Safety Release Rate requirements. However, using DIC as a stormwater management strategy, an applicant may be able to qualify for exemptions from Channel Protection and Flood Control requirements by demonstrating a 20% reduction in impervious area from the predevelopment condition to the post-development condition (Section 1.2.1). Use of Stormwater Management Trading as a compliance strategy (Section 3.2.4) precludes a project from qualifying for a Surface Green Review. Applications that fall into this category are encouraged to contact PWD prior to ERSA Application submission to confirm Expedited PCSMP Review eligibility.
2.4.3 Expedited PCSMP Review Process
An applicant who chooses to pursue either the Disconnection Green Review or Surface Green Review must declare this intent when submitting the ERSA Application (Section 2.1.1). By doing so, PWD can evaluate whether specific review requirements are being met in the Conceptual Review Phase (Section 2.3) and the applicant will know early on when, or if, infiltration testing will be required during the design process.
If the stormwater management approach changes during the plan review process and the applicant would like to consider pursuing an Expedited PCSMP Review, the applicant must contact PWD Stormwater Plan Review before resubmitting to discuss specific design and submission requirements.
The applicant is encouraged to use Stormwater Plan Review’s Standard Details, including details for green roofs, porous pavements, and bioinfiltration/bioretention basins, which are available in Appendix L of this Manual, when designing their project for Expedited PCSMP Review. Projects that are required to obtain a NPDES Permit from PA DEP should plan accordingly, as the shorter review times of PWD’s Expedited PCSMP Reviews do not affect the NPDES Permit review process (Section 2.7).