Impaired Water - Legler School Br (Legler School Branch)
Green County, Wisconsin
SP14
882900
0.01 - 5.50
5.49
Proposed for removal from impaired waters during assessment period.
Notes
Legler School Branch is a nine-mile spring fed stream in the Little Sugar River watershed that flows easterly into the Little Sugar River near New Glarus, WI. The Legler School Branch sub-watershed is 4 square miles and is used primarily for agriculture. The entire stream was listed on the 303(d) list due to degraded habitat, with sediment as the primary nonpoint source pollutant in 1998. A TMDL for this water was approved by EPA in 2005.
Riparian stream corridor improvement had the desired result of reducing streambank erosion and improving fish habitat. The macroinvertebrate community is healthy and indicates good water quality. Habitat assessments for sites that were rehabilitated, as well as for those that were not, are consistently in the good range. Therefore, the department recommends that both Legler School Branch and Pioneer Valley Creek be removed from the state?s 303(d) list of impaired waters. Delisting is recommended during the 2022 assessment cycle.
Listing Details
Pollutant
Sediment/Total Suspended Solids
Listed For
Impairments
NA
Current Use
Listing Status
Delist
Attainable Use
Priority
Not Applicable
Designated Use
303(d) ID
232
Listing Date
4/1/1998
Impaired Water Notes
Legler School Branch is a nine-mile spring fed stream in the Little Sugar River watershed that flows easterly into the Little Sugar River near New Glarus, WI. The Legler School Branch sub-watershed is 4 square miles and is used
primarily for agriculture. The entire stream is listed on the 303(d) list due to degraded habitat, with sediment as the primary nonpoint source pollutant. The 1985 Surface Waters of Green County reported that bank cover was generally good and erosion was only a problem during periods of heavy runoff. In 2001, it was noted that there were signs of severe bank erosion downstream from Legler Valley Road and cows had access to the stream. A structured habitat survey completed upstream from the 2nd Street bridge crossing in 2004 shows the stream’s bottom consists of greater than 60 percent fine sediments (68 percent silt and clay) in pools, riffles, and runs.
According to WDNR habitat rating guidelines this is considered poor habitat.

In addition, a WDNR aquatic biologist made visual observations of the
stream, noting that it was wide and shallow with highly eroded banks. Department staffs believe that sediment deposition has caused the stream to widen and become shallower to the point that it is considered poor habitat. Legler School Branch currently supports a limited forage fishery with the potential to support a warm water forage fishery or perhaps a cold water fishery. The fishery has been shown to be severely limited with one 2001 survey finding only one fathead minnow in an upstream location. Interestingly, a fish survey completed at a downstream location in 2004 found four brown trout ranging from 8.7-11.7 inches in length, one largemouth bass, and a large number of cold water indicator species such as mottled sculpin and brook stickleback. The CWIBI score for this segment of the stream was 50, which indicates “fair” coldwater biotic integrity. The abundance of cool-water species and the consequently high IBI score at this location could be due to the cool and wet nature of the summer when the survey was performed. Further fish, habitat, and temperature monitoring would be required to accurately determine the thermal regime of this
stream.
Date
6/28/2005

Impaired Water Notes
Legler School Branch (882900, miles 0-5.5) is part of the Sugar-Pecatonica River Basin and the sediment TMDLs were approved by the USEPA August 24, 2005.
Date
4/25/2005

Impaired Water Notes
Riparian stream corridor improvement had the desired result of reducing streambank erosion and improving fish habitat. The macroinvertebrate community is healthy and indicates good water quality. Habitat assessments for sites that were rehabilitated, as well as for those that were not, are consistently in the �good� range. Therefore, the department recommends that both Legler School Branch and Pioneer Valley Creek be removed from the state�s 303(d) list of impaired waters.
Date
1/25/2021