DCSM, Letters to Industry and Technical Memos

DCSM Section
Updates to Chapter 4 & 8, Erosion Control Requirements & Storm Drainage Systems of the City of Manassas Design and Construction Standards Manual (DCSM)

In December the City issued an LTI #2024-01. Since then DEQ has issued their updated draft manuals and regulations for erosion control as well as for stormwater requirements. Due to this update the City has updated this LTI with some new elements as noted in items 4 and 5 below:

Item 1: DCSM Section 8-100 - Increases in sheet flow/concentrated runoff resulting from regulated land disturbing activities associated with minor site plans submitted after December 29, 2023, including infill single family lot development, must be identified and evaluated to ensure that no downstream flooding or erosion is created or exacerbated. Engineers are recommended to contact our Engineering Department/Stormwater Division to determine if specific issues exist within their stormwater conveyance network and to discuss locations of known flooding and erosion problems. No Changes

Item 2: DCSM Section 8-500 - Currently the City’s policy is to allow pro-rata share as a compliance option for developments upstream of existing regional facilities, if they meet certain criteria. The grandfathering provision for Part IIC of the Virginia Stormwater Management Regulation is set to expire on June 30, 2024 at the end of the current Construction General permit (CGP) cycle.

As of December 29, 2023 the City will no longer allow pro-rata share as an option for stormwater management compliance and all projects will be responsible for meeting the current Virginia Stormwater Management Regulations (9VAC25-870). Projects approved under the pro-rata program are not eligible for CGP issuance or renewal as of June 30, 2024.  In addition, any project requiring CGP coverage using the pro-rata program must achieve final stabilization by June 30, 2024. Any project not requiring CGP coverage using the pro-rata program must obtain City land disturbance permit issuance by June 30, 2024. No Changes

Item 3: (Informational Only): FEMA has notified the City that they are adopting a new Flood Insurance Study (FIS). This will mean that new updated Flood Insurance Rate Maps (FIRM) will become effective on a certain date, and that the community is required to adopt a compliant floodplain management ordinance by that date to remain eligible for participation in the National Flood Insurance Program (NFIP). These changes are likely to result in changes to flood insurance requirements and rates for individual parcels in and adjacent to regulated floodplains. The City will hold a public meeting to discuss the changes and adoption of these maps prior to their effective date. The publishing of the maps has been delayed by FEMA and once they are revised and approved the City will review and hold a public meeting. Thru discussion with FEMA they stated that a community must regulate all development to effective FEMA FIRM/FIS products.  A CLOMR is a proposed change to mapping products and NOT a regulatory product.  Thus, a proposed development must meet the requirements of the effective mapping products and not what is proposed in the CLOMR until the LOMR is issued which revises the map and this would be enforced until the updated maps are approved and adopted.

Item 4: Effective July 1, 2024 the City will be adopting the latest state requirements for erosion control requirements. These requirements will take affect at that date. Site plans that are submitted following that date will need to comply with either the old standard or the latest standards during this transitional period. On July 1, 2025, the older regulations cannot be used.

Any rezoning or special use permit applications that are submitted during this transition period should comply with the latest standards so as to avoid issues and non-compliance with future site plans.

Item 5: Effective July 1, 2024 the City will be adopting the latest state requirements for stormwater requirements. These requirements will take affect at that date and site plans that are submitted following that date will need to comply with either the old standard or the latest standards during this transitional period. On July 1, 2025 the older regulations cannot be used.

Any rezoning or special use permit applications that are submitted during this transition period should comply with the latest standards so as to avoid issues and non-compliance with future site plans.

In relationship to items 4 and 5 above, the City is in the process of updating the DCSM and, once completed, will make it available on the website as a separate LTI.

For additional information please see the attached memorandum from DEQ.

Click here to view LTI 2024-01 

DCSM Section 2-800 Permits and Procedures

Adding section to require application for the Construction General Permit (CGP) and Stormwater Pollution Prevention Plan (SWPPP) when required per Virginia regulations. Requiring that all operators use the City’s SWPPP template.

LTI 2024-03
DCSM Section 2-807 – REDLINE

DCSM Section 2-400, 2-500, 2-1000, and Appendix B – Unit Price List

Updates to the City Standard Coversheet and Unit Price List

Updates to Appendix B – Unit Price List of the City of Manassas and Construction Standards Manual (DCSM) to replace the existing list and LTI #1 and #18. 

Issuance of updated City Standard Coversheet, effective February 5, 2024, to satisfy the plan submission of Article 2. Performance bond cost estimates have been removed from the coversheet and may be submitted either as a separate plan sheet or as a supplemental document with the site plan application.
To View Updates:

LTI #2024-02

Standard Cover Page

Unit Price List for Performance Bonds – Redline

Storm Drainage Systems – Article 8
DCSM Section 8-100 – City’s policy for increases in sheet flow/concentrated runoff resulting from regulated land disturbing activities associated with minor site plans (including infill single family lot development) submitted after December 29, 2023.

DCSM Section 8-500 – City’s policy for pro-rata share as a compliance option for developments upstream of existing regional facilities for site plans submitted after December 29, 2023.

DCSM Section 8-100, Minor site plans submitted after December 29, 2023, including infill single family lot development, must identify and evaluate increases in sheet flow/concentrated runoff to ensure that no downstream flooding or erosion is created or exacerbated.

DCSM Section 8-500, As of December 29, 2023, the City will no longer allow pro-rata share as an option for stormwater management compliance and all projects will be responsible for meeting the current Virginia Stormwater Management Regulations (9VAC25-850). Projects approved under the pro-rata program are not eligible for CGP issuance or renewal as of June 30, 2024.  In addition, any project requiring CGP coverage using the pro-rata program must achieve final stabilization by June 30, 2024. Any project not requiring CGP coverage using the pro-rata program must obtain City land disturbance permit issuance by June 30, 2024.

Click here to view LTI #2024-01