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03.18.2024 Legal News

Virginia Department of Environmental Quality Releases Virginia Stormwater Management Handbook

In January 2024, the Virginia Department of Environmental Quality (VDEQ) released the Virginia Stormwater Management Handbook, Version 1.0 (Handbook). The Handbook provides guidance to implement construction stormwater discharge-related water quality and water quality criteria pursuant to the new Virginia Erosion and Stormwater Management Regulation, 9VAC25-875 et seq. (VESMR). The Handbook is available here.


The Virginia Erosion and Stormwater Management Act (VESMA), enacted in 2016, required VDEQ to consolidate Virginia’s erosion and sediment control and construction stormwater management regulations, among others. However, the VESMA’s effective date was delayed until the VESMR was promulgated and became effective. That regulatory process has only recently come to fruition with the VESMR. Therefore, the VESMA, VESMR, and the Handbook are all scheduled to take effect July 1, 2024.

The Handbook replaces the very old and, in many respects, technically outdated Virginia Erosion and Sediment Control Handbook, Third Edition (1992), and the Virginia Stormwater Management Handbook, First Edition, (1999). In addition, it replaces, but also incorporates information and guidance from, several other construction stormwater management guidance documents previously issued by VDEQ and predecessor agencies.1 However, VDEQ is providing a one-year transition period to allow erosion and sediment control plans and stormwater management plans submitted between July 1, 2024, and June 30, 2025, to use either (i) the existing manuals, handbooks and guidance or (ii) the Handbook.


While the Handbook applies broadly to a variety of development projects throughout Virginia, for solar project development, one key issue (among many others) addressed in the Handbook is the implementation of VDEQ’s new solar project-related stormwater runoff calculations. As described in our prior legal alerts on this topic,2 on March 29, 2022, VDEQ issued a major new and much more stringent post-development stormwater management policy related to the consideration of solar panels as impervious surfaces for construction stormwater runoff calculations. This policy went into effect immediately.

However, after industry discussions with VDEQ, the department issued two subsequent guidance memoranda that clarified the timing for implementing the new imperviousness factor guidance. Specifically, VDEQ’s April 14, 2022, guidance memorandum stated:

“Therefore, any solar project that does not obtain an interconnection approval by a regional transmission organization or electric utility by December 31, 2024, must comply with the requirements detailed in the Department’s March 29, 2022, memorandum, which will be further clarified in an agency guidance document. Any owner or operator with a previously DEQ-approved solar project that does not obtain an interconnection approval by a regional transmission organization or electric utility on or before December 31, 2024, may submit a revised stormwater management plan to DEQ for a fast-tracked (expedited) review to verify compliance with this section. No additional plan review fee(s) will be assessed by DEQ for solar projects falling within this category.”

Then, in VDEQ’s Guidance Memo No. 22-2012 dated November 30, 2022 (also known as the Technical Design Guide),3 VDEQ further clarified that “Interconnection Approval” as used in the April 14, 2022, memorandum can be demonstrated by one of the following:

  1. Issuance of a System Impact Study as defined in PJM Manual 14a: New Services Request Process, Section 4.3 (Revision 29, Effective Date: August 24, 2021, or as amended thereafter).
  2. Issuance of an equivalent study by PJM under any process approved by the Federal Energy Regulatory Commission (FERC) that results from the PJM Interconnection Reform Process.
  3. Issuance of a Small Generator Interconnection Agreement for projects that go through the state interconnection process.
  4. Submission, and acceptance, of an initial interconnection service request application to a regional transmission organization or electric utility.

While the Handbook largely incorporates items 1, 2 and 3 of Guidance Memo 22-2012 within Section of the Handbook, item 4 was incorporated into the Handbook differently and with major implications, as follows:

“Additionally, if an owner or operator wants to confirm whether the stronger post-development stormwater requirements will apply to a particular project, 'Interconnection Approval' may also be demonstrated by PJM approval of a new service request on or before April 14, 2022.”

Notably, compared with item 4 of VDEQ’s Guidance Memo No. 22-2012, the Handbook addresses the “new service request” scenario under item 4 differently insofar as: (i) it incorporates a much earlier cutoff date of April 14, 2022 for submission and acceptance of an initial service request (rather than December 31, 2024); (ii) it only references PJM as the regional transmission organization as the potential recipient and reviewer of the initial service request (and not any electric utility), and (iii) it uses the term “approval” regarding the initial service request (rather than “acceptance”). These changes, if intentional, will have the effect of grandfathering fewer solar projects from the new solar panel impervious factor if such projects are intended to utilize item 4 of VDEQ’s Guidance Memo No. 22-2012. Virginia solar industry developers and operators are understandably concerned about the effect of this major change from VDEQ’s Guidance Memo No. 22-2012.

VDEQ is soliciting public comments on the Handbook through March 27, 2024. Comments may be submitted via the Virginia Regulatory Town Hall website, which is available here.

For more information or any questions, please contact any of the authors or the Williams Mullen attorney with whom you may already work. 

1For a list of such guidance documents, please see VDEQ memorandum entitled “Guidance Memo No. GM24-2001 – Virginia Stormwater Management Handbook, Version 1.0”, dated January 29, 2024, available here.
2Available here and here.
3Available here.