Many of Kentucky’s streams showing improved water quality; New exceptional waters identified

The Division of Water, as part of its triennial review of water quality standards, is proposing to add 20 new waterbodies as outstanding state resource waters (OSRWs) and 13 new waterbodies as “Exceptional” waters. The number of waterbodies included as OSRWs and “Exceptional” waters are good indicators of water quality improvement. The list of OSRWs, which include the highest quality waterbodies in Kentucky and those waterbodies that support threatened and endangered species, has grown from 157 OSRWs in 2008 to 423 designated OSRWs in 2015. The list of “Exceptional” waters, including Reference Reach Waters has also grown, from a list of 118 waterbodies listed as having “Exceptional” water quality and aquatic habitats, to 254.


Kentucky water quality standards regulations identify six designated uses for surface water to meet the policy and purpose of water quality in the Commonwealth. The designated uses as identified in 401 KAR 10:026 are: warm water aquatic habitat;  cold water aquatic habitat; primary contact recreation; secondary contact recreation; domestic water supply; and outstanding state resource water (OSRW). The OSRW designated use protects certain unique waters of the commonwealth by automatically including waters designated pursuant to the Kentucky Wild Rivers Act, KRS 146.200-146.360; waters designated pursuant to the Federal Wild and Scenic Rivers Act, 16 U.S.C. 1271-1287; and waters that support federally recognized endangered or threatened species pursuant to the Endangered Species Act of 1973, as amended, 16 U.S.C. 1531-1544. Other surface waters are considered for inclusion in this category if they are considered to be in an Exceptional Waters category.

Wild river story map

”Exceptional” waters is also protected under the Kentucky antidegradation policy, meaning these waters are of higher water quality than those water bodies meeting either the cold water or warm water aquatic habitat designated use, and are afforded additional protections.  This category of water is based on an ‘exceptional’ fish or macroinvertebrate community, or ‘exceptional’ habitat.


The Division of Water manages numerous monitoring programs to determine the water quality conditions of the Commonwealth’s streams, rivers, springs, lakes and reservoirs.

These programs generally align with three broad strategies:

  1. Monitor streams, rivers, reservoirs and lakes to identify water quality. This includes monitoring waterbodies with high quality aquatic habitats; monitoring Reference Reach water bodies to detect trends in water quality; targeting watersheds to investigate emerging water quality concerns or issues; monitoring fish tissue and drinking water supplies for human health consumption; and monitoring to determine the effectiveness of watershed projects implemented to control pollution problems.
  2. Monitor stream health through random (probabilistic) aquatic biological surveys. The probabilistic program results provide statistical data to enable the agency to extrapolate current aquatic conditions for a given river basin.
  3. Conduct focused water quality monitoring in watersheds that require a total maximum daily load (TMDL) developed for pollutants. TMDL monitoring identifies specific sources of the pollutants causing the stream to be impaired (not meeting one or more designated uses). These studies generate data to enable the Division to determine how much pollutant load a waterbody can receive and meet its designated uses and identify pollutant loading reductions necessary to restore a waterbody such that it meets its designated uses.

Data generated by these various monitoring programs are used to make assessments as to whether the waterbodies monitored are meeting their designated uses. The assessment results are compiled into an Integrated Report on water quality. This biennial report is required of states by the Clean Water Act as a means to communicate the conditions of each state’s water resources. The assessment results reflect, to some degree, the effectiveness of the implementation of water quality standards adopted by the Commonwealth to maintain healthy water bodies for fishing, swimming, boating, fish consumption, and to provide safe drinking water. Waterbodies that fail to meet one or more designated uses are compiled on the impaired waters (303(d)) list.

Water bodies that do not support one or more designated uses may be monitored at a later date to determine if land-use changes, facility upgrades, or projects implemented to abate sources of pollutants have effectively restored water quality. If one or more pollutants that had previously failed to meet water quality standards now meet the standards, the Division provides the data and technical rationale that supports removing the pollutant or designated use of a waterbody segment from the 303(d) list. The number of waterbodies that have been removed from the 303(d) list is another indicator of water quality improvement

The Division of Water also recently published the Draft 2014 Clean Water Act Section 303(d) list for public comment. The Division is proposing in this report to remove from the impaired waters list 60 waterbodies and stream segments that are now meeting water quality standards. Of which, 26 stream segment are from the Ohio River that are now meeting the methylmercury fish tissue standard. Since 2008, the Division of Water has determined that 284 waterbodies and stream segments previously listed as “impaired” are subsequently meeting water quality standards.

Delist Chart