Publication Number 442-559, Posted January 2006
margin of safety (MOS) - a required component of the TMDL that accounts for the uncertainty in calculations of pollutant
loading from point, nonpoint, and background sources.
nonpoint source (NPS) pollution - pollution originating from diffuse sources on and above the landscape. Examples include runoff from fields, storm-water runoff from urban landscapes, roadbed erosion in forestry, and atmospheric deposition. point source pollution - pollution discharged at a specific location. Point source discharges are generally regulated through the Virginia Pollution Discharge Elimination System (VPDES) permitting procedures. total maximum daily load (TMDL) - a pollution "budget" that defines the maximum amount of a particular pollutant a water body can assimilate without violating water quality standards. Mathematically, a TMDL is written as TMDL = WLAs + LAs + MOS. TMDLs include pollution from Waste Load Allocations (WLAs) (point sources) and Load Allocations (LAs) (nonpoint sources). In addition, the TMDL includes a margin of safety (MOS). A TMDL is developed for a specific pollutant and can be expressed in terms of mass per time, or other appropriate measure that relates to the water quality standard being violated. TMDL implementation plan (IP) - a document required by Virginia statute detailing the set of pollution control measures needed to remediate an impaired water body. water quality standards - a group of statements that constitute a regulation describing specific water quality requirements. WQMIRA - the Water Quality Monitoring, Information, and Restoration Act of 1997 (ยค62.1-44.19:4 through 19:8 of the Code of Virginia). |
best management practices (BMPs) - reasonable and cost-effective means to reduce the likelihood of pollutants entering a water body. BMPs include riparian buffer strips, filter strips, nutrient management plans, conservation tillage, etc. |
What happens in a Focus Group?
Focus groups are asked to perform specific tasks: identifying
what corrective actions are needed/feasible from
their perspectives, identifying ways to overcome obstacles
to implementing the needed corrective actions, identifying
funding partners, identifying existing programs
and resources that might be relevant, and proposing
additional programs that might support implementation
of needed corrective actions.
What does the Steering Committee do?
The steering committee provides oversight for the TMDL
IP development process, gathers information from focus
groups, and synthesizes that information. The steering
committee then makes decisions about the content and
direction of the TMDL IP that balance the interests represented
in the focus groups. Membership on this committee
is typically comprised of stakeholders from the
various focus groups, representatives from the state and
local governments, and watershed interest groups that
are involved in developing the TMDL IP. The steering
committee's responsibilities include developing grant
proposals to fund water quality improvement activities,
overseeing citizen monitoring efforts to track water quality
improvements, and working to ensure that an active,
productive partnership designed to improve water quality
is maintained between state and local governments and
the stakeholders. The steering committee is responsible
for investigating how the TMDL implementation effort
can be integrated with existing or proposed water quality
restoration efforts, and ensuring that the TMDL IP is
successfully integrated into these water quality restoration
efforts.
Examples of TMDL implementation efforts in rural watersheds include the north River watershed located in Rockingham County (northwest Virginia), the Middle Fork holston River watershed located in Washington County (Southwest Virginia), and the Blackwater River watershed located in Franklin County (Southwest Virginia). All include stream segments contaminated by fecal coliform bacteria. TMDL implementation began in these impaired watersheds in 2001, and water quality is improving. Data from these watersheds shows a decreasing trend in fecal coliform concentrations. oversight and management for TMDL implementation in these watersheds is provided by local Soil and Water Conservation Districts (SWCDs). Land use in these watersheds is predominantly agriculture and forest, and livestock-exclusion stream fencing has been the primary corrective action implemented. other corrective actions include encouraging septic tank maintenance, eliminating straight pipes, repairing and replacing failing septic systems, planting cover crops, implementing nutrient management, installing vegetative cover on critical areas, establishing forested riparian buffers, reforesting, and constructing animal waste management facilities.
fecal coliform bacteria - bacteria originating in the intestinal tract of warm-blooded animals and passing into the environment in feces. Fecal coliform bacteria are often used as an indicator of pathogens in water. |
Four Mile Run, located in Arlington and Fairfax counties in northern Virginia is an example of TMDL implementation in an urban watershed. The Four Mile Run TMDL Implementation Plan was completed in 2004. The Four Mile Run fecal coliform TMDL was approved in 2002. The impairment was attributed primarily to urban nonpoint sources of fecal coliform. The Four Mile Run TMDL IP is focusing its implementation efforts using a three-pronged strategy: 1. Pollution Prevention - targeting bacteria reduction at the source by enacting pet waste ordinances, eliminating illicit sewer discharges, etc.; 2. Mitigation measures - controlling or reducing the transport of bacteria through disinfection and the use of control measures that reduce stormwater volumes; and . Indirect Measures - education and outreach programs designed to inform the citizenry of water quality issues, and ultimately, to change behaviors and attitudes towards water quality. Partners in the Four Mile Run project include the following governmental agencies: northern Virginia Regional Commission, northern Virginia Regional Park Authority, City of Alexandria, City of Falls Church, Arlington County, Fairfax County, Virginia Department of Transportation, Virginia Department of Environmental Quality, and Virginia Department of Conservation and Recreation.
Public Participation
This section of the IP should contain a description
of the process used to engage stakeholders (mail
campaigns, radio/television exposure, etc.) and the
number, location, and attendance of working group,
steering committee, and other public meetings.
Implementation Actions
This section contains descriptions and numbers
of corrective actions needed to attain the source
allocations in the TMDL, projected costs, and anticipated
benefits. This section should also include a
discussion of ordinance and policy changes recommended
by stakeholders to improve water quality,
and a description of needed education and outreach
activities and those responsible for conducting
those activities.
Measurable Goals and Milestones
Implementation milestones and goals to be achieved
during implementation are described in this section
of the IP. In addition, the type and extent of water
quality monitoring required during implementation
is included here.
Stakeholders' Roles and Responsibilities
In this section, the roles of various stakeholders,
including federal, state, and local governments, local
businesses, community organizations, and private
citizens are described. These roles can include writing
grant proposals to secure funding to implement
corrective actions, being active in citizen monitoring
groups, promoting public awareness through education
and outreach, and supporting implementation
efforts through local programs.
Integration with Other Watershed Plans
This portion of the IP details how implementation
efforts will dovetail with other existing watershed
management efforts and local comprehensive plans.
One example is integrating corrective action implementation
with activities associated with Municipal
Separate Storm Sewer System (MS4) storm-water
permits in urbanized areas.
Robert Brent, Valley Regional TMDL Coordinator, Virginia Department of Environmental Quality
Charles Lunsford, TMDL Program Manager, Virginia Department of Conservation and Recreation
TMDLs (Total Maximum Daily Loads) - Terms and Definitions, Virginia Cooperative Extension publication 442-550, http://www.ext.vt.edu/pubs/bse/442-550/442- 550.pdf
Microbial Source Tracking and the TMDL (Total Maximum Daily Loads) Process, Virginia Cooperative Extension publication 442-554, http://www.ext.vt.edu/ pubs/bse/442-554/442-554.pdf
TMDLs (Total Maximum Daily Loads) for Bacteria Impairments, Virginia Cooperative Extension publication 442-555, http://www.ext.vt.edu/pubs/bse/442- 555/442-555.pdf
TMDLs (Total Maximum Daily Loads) for Benthic Impairments, Virginia Cooperative Extension publication 442-556, http://www.ext.vt.edu/pubs/bse/442- 556/442-556.pdf
For a complete listing of Virginia Cooperative Extension publications, fact sheets, and bulletins, please go to http://www.ext.vt.edu/resources.
TMDL Five-year Progress Report. http://www.deq.virginia.gov/tmdl/pdf/04prgrpt. pdf, Virginia Department of Environmental Quality, Richmond, Va., January 2005.
Virginia DEQ: Background Information on Virginia's TMDL Program. http://www.deq.virginia.gov/tmdl/backgr.html, Virginia Department of Environmental Quality, Richmond, Va., September 2004.
Willis River Water quality Implementation Plan (Fecal Coliform TMDL) Executive Summary. http://www.deq.state.va.us/tmdl/implans/drafts/willisip. pdf, Map Tech, Inc., Blacksburg, Va., June 2005.
Implementation Plan for the Fecal Coliform TMDL (Total Maximum Daily Load) for Four Mile Run, Virginia. http://www.deq.state.va.us/tmdl/implans/4mileip.pdf, Northern Virginia Regional Commission, Annandale, Va., March 2004.
View this document in PDF format