Surface Water Designated Uses
A stream classification system based on aquatic organisms has been established by the Wisconsin Department of Natural Resources (WDNR; Chapter NR 102 of the state Administrative Code). This classification system provides an indication of water quality conditions and fishery classification for all Dane County streams. The WDNR designates surface water uses into four general categories that are defined in NR 102.04, Wis. Adm. Code. The Fish and Aquatic Life subcategories for streams/rivers are listed below. Hover over each box for a short description.
Photo By: Mike Kakuska
|COLD||Coldwater Community: Surface waters capable of supporting a coldwater sport fishery, or serving as a spawning area for salmonids and other coldwater fish species. Representative aquatic life communities associated with these waters generally require cold temperatures and concentrations of dissolved oxygen that remain above 6 mg/L. Since these waters are capable of supporting natural reproduction, a minimum dissolved oxygen concentration of 7 mg/L is required during times of active spawning and support of early life stages of newly-hatched fish.|
|WWSF||Warmwater Sport Fish Community: Surface waters capable of supporting a warmwater-dependent sport fishery. Representative aquatic life communities associated with these waters generally require cool or warm temperatures and concentrations of dissolved oxygen that do not drop below 5 mg/L.|
|WWFF||Warmwater Forage Fish Community: Surface waters capable of supporting a warmwater-dependent forage fishery. Representative aquatic life communities associated with these waters generally require cool or warm temperatures and concentrations of dissolved oxygen that do not drop below 5 mg/L.|
|LFF||Limited Forage Fish Community: Surface waters capable of supporting small populations of forage fish or tolerant macroinvertebrates (aquatic insects) that are tolerant of organic pollution. Typically limited due to naturally poor water quality or habitat deficiencies. Representative aquatic life communities associated with these waters generally require warm temperatures and concentrations of dissolved oxygen that remain above 3 mg/L.|
|LAL||Limited Aquatic Life Community: Surface waters capable of supporting macroinvertebrates or occasionally fish that are tolerant of organic pollution – typically small streams with very low flow and very limited habitat, certain marshy ditches, concrete-lined drainage channels, and other intermittent streams. Representative aquatic life communities associated with these waters are tolerant of many extreme conditions, but typically require concentrations of dissolved oxygen that remain about 1 mg/L.|
|FAL||Fish and Aquatic Life Community: Waters that do not have a specific use designation subcategory assigned but which are considered fishable, swimmable waters.|
|Source: Wisconsin 2018 Consolidated Assessment and Listing Methodology|
The current use is the fish and aquatic life community the WDNR biologist believes the water currently supports. The attainable use is the use the WDNR biologist believes the water could be attained by managing controllable sources of impairment. A waterbody’s more formal designated use is the water classification DNR uses to determine water quality criteria and effluent limits under NR 102 and NR 104 Wis. Adm. Code.
Outstanding and Exceptional Waters
Outstanding Resource Waters (ORW) and Exceptional Resource Waters (ERW) are listed in Chapter NR 102. These designations are intended to meet federal Clean Water Act obligations requiring Wisconsin to adopt an “anti-degradation” policy that is designed to prevent any lowering of water quality.More
ORWs receive the state’s highest protection standards, with ERWs a close second. ORWs and ERWs share many of the same environmental and ecological characteristics such as high recreational value, valuable fisheries and wildlife habitat. ORWs do not receive wastewater discharges, and point source discharges will not be allowed in the future unless the quality of such discharges meets or exceeds the quality of the receiving water. ORWs include national and state wild and scenic rivers. Many of the rivers are Class I or Class II trout waters. Water quality should not be lowered in these waters. ERW are not significantly impacted by human activities and provide valuable fisheries or unique habitat features. They may already receive wastewater discharges or may receive future discharges necessary to correct environmental or public health problems. Like the ORWs, many of these are Class I and II trout streams.
303 (d) List of Impaired Waters
Section 303 (d) of the Clean Water Act requires states to report all waters not meeting the set of water quality criteria associated with their designates uses.More
These criteria can be numeric or narrative. In Wisconsin, numeric criteria have been established for parameters including pH, dissolved oxygen, temperature, and for concentrations of specific chemicals, such as total phosphorus and chloride. The narrative criteria qualitatively describe conditions that should apply to a water body. They concern such matters as objectionable deposits, excess debris and scum, unsightliness, odor and taste.
A list of impaired water bodies must be submitted to the U.S. Environmental Protection Agency every two years, with the goal of water bodies being delisted as water quality problems are corrected. View pending changes including proposed additions and deletions for the list on DNR's Water Condition Viewer. DNR's current list includes 8 beaches, 11 lakes, and 42 rivers in Dane County - a total area of 47 square miles of lakes and 378 miles of rivers. For each waterbody, DNR determines the pollutant that is causing degradation and classifies the impairment. For beaches, the E. coli causes recreational restrictions. For lakes and rivers, too much phosphorus is the leading pollutant. Phosphorus is associated with many impairments, such as degraded habitat, degraded biological community, low levels of dissolved oxygen (DO), water quality use restrictions, and excess algal growth. Learn more more about how these stressors impact water quality here.
DNR implements strategies to restore water quality for degraded water bodies. Restoration mechanisms include development and implementation of “total maximum daily load” (TMDL) analyses. A TMDL analysis determines how much pollutant a water body can assimilate before it exceeds water quality standards. TMDL analyses involve:
- Identification of all sources of the pollutant(s) of concern,
- Allocation of discharges from point and nonpoint sources of pollution,
- And interactive monitoring and modeling to ensure the biological community and/or chemical status of the waters is fully restored
Explore the Maps
- Designated Uses: Click on a stream or lake to see its name and whether its designated use matches its attainable use and current use.
- Impaired and Exceptional Waters: Waters that are currently listed as impaired, those that have been delisted, and those that are designated as outstanding or exceptional.
- Pollutants of Impaired Waters: Select a pollutant or impairment to see which waters are impaired. You can also search through the names of local impaired waters.
- General Condition: See how water quality in streams and lakes for different regions of Dane County compare.
- Zoom in to see all layers.