The Designated Use-Support Rating represents water quality as a snapshot in time and space. The Designated Use-Support Rating is calculated quaterly from samples that are collected at fixed network monitoring sites. The Rating is reflective only
of conditions present at the time of sample collection. The Rating carries no expressed or implied guarantee of water quality conditions at a given location. The Rating is applicable only
at the watershed scale, and is developed primarily for long-term trending of water quality conditions.
The term "supporting" refers to the stream being able to support its designated use according to the NC Division of Water Quality. The term "impaired" means that the stream does not support its designated use according to its classification. All surface waters in North Carolina are assigned a primary classification by the NC Division of Water Quality. All waters must at least meet the standards for Class C waters. Click here
for additional information regarding NC stream classifications and designated use.