Fish and Aquatic Life
Originating from surface springs in Green County, the stream flows westward into Lafayette County where it eventually joins the East Branch Pecatonica River. The stream has an existing use as a Class II trout stream for all of its length. The most recent fish survey conducted in 1980 indicated limited numbers of trout and low diversity of species. The stream is still stocked with brown trout however. Although macroinvertebrate sampling conducted in 1990 indicated “very good” water quality, lack of diversity of species indicates stream disturbance. Water quality is likely impacted considering the low numbers and lack of diversity in fish (Marshall, 1991).
Goals of the priority watershed project were to reduce organic loading and erosion by more than 50%, improve trout fisheries, improve and stream and wildlife habitat, and increase aquatic diversity. The stream is stocked annually with brown trout. It has not been evaluated recently.
Author James Amrhein
Originating from surface springs, this stream trickles westward through hardwood forest and pasture into Lafayette County, where it eventually enters the East Branch of the Pecatonica River. The bottom is primarily a mixture of gravel, muck and silt, although some sand, rubble and boulders are also present. Veronica grows in its cold, clear water.
In Lafayette County, the stream provides fishing for both brown and brook trout, but in Green County it is too small to be stocked with yearling trout. Occasional trout undoubtedly enter Green County from the lower stretches and the headwaters probably provide an important habitat for trout fingerlings. Wildlife values are minimal. Public access on Brennan Creek is limited to a DNR easement with 0.7 miles of frontage.
Surface Acres = 0.4. Length = 1.5 t1iles. Gradient = 60 ft./mi.. Base Discharge = 0.5 cu. ft./sec.
Bush, D.M., R. Cornelius, D. Engle, and C.L. Brynildson. 1980. Lake and Stream Classification Project. Surface Water Resources of Green County, 2nd Edition. Wisconsin Department of Natural Resources, Madison, Wisconsin.
Author Surface Water Inventory Of Wisconsin
This creek originates from surface springs in Green County and flows in a westerly direction to the East Branch of the Pecatonica River. It is consideredas a better than average trout stream and is stocked annually with brown trout.
Its watershed area consists of about half agricultural and halfwooded land wiith fresh meadow covering much of the floodplain. Upland game habitat can beconsidered good. Erosion can be considered moderate in the lower portion of this stream. The bottom type consists of sand and silt. There is Division of Conservation easement along the stream just west of the Green County line. It is also accessible from two road bridges.
Brennan Creek, T3N, R5E, Sections 15-1, Surface acres = 1.5, Miles = 2.3, Gradient = 26.1 feet per mile, Total alkalinity = 189 mg/l, Volume of flow = 0.7 cfs.
From: Piening, Ronald; Poff, Ronald; Threinen, C.W., 1967. Lake and Stream Classification Project. Surface Water Resources of Lafayette County, Wisconsin Department of Natural Resources, Madison, WI.
Author Surface Water Inventory Of Wisconsin
Wisconsin has over 84,000 miles of streams, 15,000 lakes and milllions of acres of wetlands. Assessing the condition of this vast amount of water is challenging. The state's water monitoring program uses a media-based, cross-program approach to analyze water condition. An updated monitoring strategy (2015-2020) is now available.
Compliance with Clean Water Act fishable, swimmable standards are located in the Executive Summary of Water Condition in 2016 . See also 'monitoring' and 'projects'.
Wisconsin's Water Quality Standards provide qualitative and quantitative goals for waters that are protective of Fishable, Swimmable conditions [Learn more]. Waters that do not meet water quality standards are considered impaired and restoration actions are planned and carried out until the water is once again fishable and swimmable
Management goals can include creation and implementation of a Total Maximum Daily Load Analysis, habitat restoration work, partnership education and outreach and more. If specific recommendations exist for this water, they will be displayed below.
Monitoring the condition of a river, stream, or lake includes gathering physical, chemical, biological, and habitat data. Comprehensive studies often gather all these parameters in great detail, while lighter assessment events will involve sampling physical, chemical and biological data such as macroinvertebrates. Aquatic macroinvertebrates and fish communities integrate watershed or catchment condition, providing great insight into overall ecosystem health. Chemical and habitat parameters tell researchers more about human induced problems including contaminated runoff, point source dischargers, or habitat issues that foster or limit the potential of aquatic communities to thrive in a given area. Wisconsin's Water Monitoring Strategy was recenty updated.
Grants and Management Projects
|WBIC||Official Waterbody Name||Station ID||Station Name||Earliest Fieldwork Date||Latest Fieldwork Date||View Station||View Data|
|905700||Brennan Creek||10016967||Brennan - Hwy 78||4/26/1990||4/26/1990||Map||Data|
|905700||Brennan Creek||10048152||Brennan Creek at Valley Rd||Map||Data|
|905700||Brennan Creek||10016963||Brennen Cr. - Private Drive By Sth 78||6/11/1986||6/11/1986||Map||Data|
|905700||Brennan Creek||10017133||Unnamed Trib/Pecatonica E Br - Site #16 - E Brennan Ln Just off Hwy 78 Betw. Brennan & 78 BridgesLafayette Co.||10/30/1990||10/30/1990||Map||Data|
Brennan Creek is located in the Lower East Branch Pecatonica Rivers watershed which is 144.80 mi². Land use in the watershed is primarily agricultural (76%), forest (16%) and a mix of suburban (4%) and other uses (3%). This watershed has 370.96 stream miles, 107.68 lake acres and 2,029.49 wetland acres.
Nonpoint Source Characteristics
This watershed is ranked Not Available for runoff impacts on streams, Not Available for runoff impacts on lakes and High for runoff impacts on groundwater and therefore has an overall rank of High. This value can be used in ranking the watershed or individual waterbodies for grant funding under state and county programs.However, all waters are affected by diffuse pollutant sources regardless of initial water quality. Applications for specific runoff projects under state or county grant programs may be pursued. For more information, go to surface water program grants.