Regulatory Side

303(d), 305(b)

and TMDL’s

303(d)

- The 303(d) List is a compilation of the streams and lakes in

   Tennessee that are “water quality limited” or are expected to

   exceed water quality standards in the next two years and

   need additional pollution controls. Water quality limited

   streams are those that have one or more properties that violate

   water quality standards. They are considered impaired by

   pollution and not fully meeting designated uses.

- Additionally, the 303(d) List prioritizes impacted streams for

 (TMDL)

Tennessee 303(d)

- In Tennessee, the most common reasons for a river or

  reservoir to be posted are the presence of high levels of

  bacteria in the water or PCBs, chlordane, dioxins, or mercury

  in fish tissue. Currently 62 streams, rivers, and reservoirs in

  Tennessee have been posted due to public health threat. A

  current list of advisories is posted on the department’s home

  page Click on the link below:

 

305(b)

- Using a standardized assessment methodology, monitoring

  data from individual streams are compared to water quality

  standards. Violations of water quality standards are identified

  and the degree to which each individual water body meets

  its designated uses is determined. Assessment categories

  recommended by EPA are used to characterize water quality.

- Assessment results are compiled and reported to the public

  quality assessment reporting are the 305(b)

  Report and the 303(d) List.

Water Quality Criteria

- The Tennessee Water Quality Control Board has assigned

  specific water quality criteria to each designated use. These

  criteria establish the water quality needed to support each

  use. Since ever water-body has multiple uses, it may have

  multiple applicable criteria. The standard for each stream

  is based on the most stringent criterion for the uses assigned

  to it. The most stringent criteria are the protection of fish

TMDL

What is a TMDL?

- A Total Maximum Daily Load (TMDL) is a study that (1)

  qualifies the amount of a pollutant in a stream, (2)

  identifies the sources of the pollutant, (3) and recommends

  regulatory or other actions that may need to be taken in

  order for the stream to no longer be polluted.