Impaired Water - Legler School Br (Legler School Branch)
Green County, Wisconsin
SP14
882900
0.01 - 5.50
5.49
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
TMDL approved 2005.
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.
This water was assessed during the 2014 listing cycle; total phosphorus and biological (macroinvertebrate or fish Index of Biotic Integrity (IBI) scores) sample data clearly met 2014 WisCALM listing thresholds for the Fish and Aquatic Life use.

Assessments during the 2020 listing cycle showed new fish sample data were in good condition.
Listing Details
Pollutant
Sediment/Total Suspended Solids
Listed For
Fish and Aquatic Life
Impairments
Degraded Habitat
Current Use
LFF - Limited Forage Fishery
Listing Status
TMDL Approved
Attainable Use
WWSF - Warmwater Sport Fishery
Priority
Not Applicable
Designated Use
WWSF - Warmwater Sport Fishery
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