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Water: Total Maximum Daily Loads (303d)


Past Conferences

Nutrient TMDL Workshop

February 15-17, 2011, Sheraton New Orleans, LA
EPA Regions 4, 5, 6, 7 and 8, together with EPA HQ, teamed up to offer a training workshop on the current practices being used in the Clean Water Act Section 303(d) Program to address waters impaired by nutrients. Thousands of waterbodies in the U.S. are impaired by the nutrient pollutants, nitrogen and phosphorus, and numerous challenges are associated with developing effective Total Maximum Daily Loads (TMDLs) for such waters. The purpose of this training workshop was to bring together EPA and state staff involved in the Clean Water Act Section 303(d) Program to exchange information related to development of nutrient TMDLs. The three day workshop covered a broad range of topics including section 303(d) listing, TMDL development, and TMDL implementation for nutrient-impaired waters.

Agenda (with links to materials)| PDF Version (5 pp, 199K, About PDF)

Summary of Proceedings (PDF) (30 pp, 607K, About PDF)



BASINS and Other Training Sponsored by OST

EPA's Office of Science and Technology sponsors a week-long course on using Better Assessment Science Integrating point and Nonpoint Sources (BASINS) which is a software tool to perform integrated water quality and watershed analyses. The course covers an introduction to the basic geographic information (GIS) operations, BASINS environmental data layers, nonpoint source modeling, and in-stream water quality assessments. The course includes extensive hands-on computer applications.

Persons interested in watershed management, development of total maximum daily loads (TMDLs), coastal zone management, nonpoint source programs, water quality modeling, National Pollutant Discharge Elimination System (NDPES) permitting, and other related programs are urged to attend. Participants should have a background in water quality modeling, a basic understanding of GIS applications, and familiarity with the Windows environment. Familiarity with ArcView (ver. 3) basic operations is a plus.

OST is also sponsoring several other training courses on the use of various models including: HSPF, CORMIX, etc. See the BASINS Web site for more details.


Archived Versions of TMDL Webcasts

National Association of Counties (NACo) "Stormwater Runoff for Counties" Webinar, November 12, 2009

This Webinar, with a targeted audience of NACo members and funded in part by EPA grant number 83342601, describes how counties protect vital waterways, lakes, ponds and drinking water from pollutants on streets, driveways and roofs. Materials from the Webinar follow:

ATTAINS: A Gateway to State-Reported Water Quality Information, June 18, 2008

EPA recently released a new Web site where water quality managers and the public can go to view a wide range of state-reported water quality information. This Web site, sometimes referred to as ATTAINS, combines two formerly separate databases: the National Assessment Database and the National Total Maximum Daily Load (TMDL) Tracking System. The National Assessment Database is for water quality assessment information reported by the states under section 305(b) of the Clean Water Act, while the National TMDL Tracking System is for impaired waters information reported by the states under section 303(d) of the Clean Water Act. ATTAINS gives the “full story” showing which waters have been assessed, which are impaired, and which are being (or have been) restored. This Web site allows the user to view dynamic, continuously updated tables and charts that summarize state-reported information for the nation as a whole, for individual states and waters, and for the ten EPA Regions. Visit ATTAINS.

Options for Expressing Daily Loads in TMDLs, Jan. 8, 2008

This Webcast introduces EPA’s recently released draft document, Options for Expressing Daily Loads in TMDLs. The Webcast is designed to provide information to TMDL practitioners regarding options for developing appropriate daily load expressions during the TMDL process. In particular, the Webcast addresses the calculation of daily loads for TMDLs that use allocation time frames that are greater than daily (e.g., annual, seasonal).

The ABCs of TMDLs for Stakeholders, Sept. 18, 2005

Over the last decade, the TMDL Program has gone from a somewhat ignored water quality planning program to a program found in just about every water quality manager’s toolbox. A simple Google search for "total maximum daily loads" now exceeds two million hits in less than a second. What is this program and why all the attention? Who develops TMDLs, why do they develop them and how do they fit into the watershed process? What is a "303(d)" list and "integrated report" and why should we pay attention to these? This Webcast provides an introduction to the 303(d)-listing and TMDL Programs. Case examples illustrate the various principles of the TMDL Program and how this program is being used to guide water quality control decisions in both the point source and nonpoint source arenas. The Webcast also describes how you can be involved in the 303(d) listing and TMDL development efforts in your watershed.




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