Download the TMDL IP Guidance Manual (PDF).

This manual provides guidance to local governments, soil and water conservation districts, planning district or regional commissions, community watershed groups, and state and federal agencies on developing Implementation Plans (IPs) for waters where TMDLs have been completed. It also addresses the requirements for IPs as outlined in Virginia's 1997 Water Quality Monitoring, Information, and Restoration Act (§62.1-44.19:4 through 19:8 of the Code of Virginia), or WQMIRA. In addition to the requirements of WQMIRA, this guidance manual addresses the requirements of IPs based on EPA's "Guidance for Water-Quality Based Decisions: The TMDL Process," "Supplemental Guidelines for the Award of Section 319 Nonpoint Source Grants to States and Territories," and "Guidance for Developing Watershed-Based Plans for Impaired Waters."

An IP is prepared at some point following development of the TMDL, and approval by EPA. The TMDL represents the maximum amount of pollutant that a water body (stream, lake, or estuary) can receive without exceeding water quality standards. TMDLs are pollutant-specific so that each water body in which multiple pollutants violate water quality standards will have multiple TMDLs. The TMDL consists of a waste load allocation (WLA) or point source contribution; a load allocation (LA) or nonpoint source (NPS) allocation; and a margin of safety (MOS). IPs are not necessarily pollutant-specific and should be designed to address multiple water quality problems within a water body or all water quality-impaired water bodies within a watershed.

Section 303(d) of the Clean Water Act and the EPA's Water Quality Planning and Management Regulation (40 CFR Part 130) require states to develop TMDLs for water bodies that are exceeding water quality standards. Once the TMDL has been developed, a TMDL report is prepared and distributed for public comment and then submitted to EPA for approval. Following this process, an IP should be developed to describe actions (i.e., best management practices) to implement the allocations contained in the TMDL. In most cases, the WLAs would be addressed through the Virginia Pollutant Discharge Elimination System (VPDES) Program administered by the Virginia Department of Environmental Quality.

Revisions of this manual may be necessary due to statutory or regulatory changes. As changes occur, periodic additions or supplements will be prepared for inclusion into the manual. If you have any questions about this manual, please contact Craig Lott (DEQ) at (804) 698-4240 or Craig.Lott@deq.virginia.gov, or Charlie Lunsford (DCR) at (804) 786-3199 or Charlie.Lunsford@dcr.virginia.gov.