Watershed Management Cycle

The watersheds in Tennessee have been divided into five groups based on the year of implementation in a five-year cycle. The Division of Water Pollution Control bases its activities for each group by the group's position in the cycle. The cycle also coincides with the issuance and duration of discharge permits. The watershed cycle is illustrated below.

Six key activities occur during the cycle:

1. Planning. Existing data and reports from appropriate federal, state, and local agencies and citizen-based organizations are compiled and used to describe the quality of rivers and streams, and to determine monitoring priorities. Priority streams are those on the 303(d)-List, previously nonassessed, or believed to exhibit a change in water quality since they were monitored last.

2. Monitoring. Field data is collected by TDEC staff for streams previously prioritized. These data supplement existing data and are used for water quality assessments.

3. Assessment. Monitoring data is used to determine if the streams support their designated uses based on stream classifications and water quality criteria. The assessment is used to create the 303(d) List and the 305(b) Report. Following the assessment, a public meeting is conducted to inform the public of the most recent results.

4. Wasteload Allocation/TMDL. Monitoring data is used to determine pollutant limits for permitted dischargers releasing wastewater to the watershed. Limits are set to ensure that state water quality is protective. TMDLs are studies that determine the point and nonpoint source contributions of a pollutant in the watershed.

5. Permits. Issuance and expiration of all discharge permits is synchronized to the five-year watershed cycle. Approximately 1,350 individual permits are issued by Tennessee under the National Pollutant Discharge Elimination System (NPDES).

6. Watershed Water Quality Management Plans. These watershed plans include a general watershed description, water quality assessment summary results, inventory of point and nonpoint sources, water quality concerns, federal, state, and local initiatives, and management strategies. A public meeting is held to discuss the draft plans with local citizens, elected officials, and the regulated community.

A timeline for these activities is shown below: