Trempealeau County, Wisconsin
BR01
1686900
1.64 - 3.54
1.90
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
On 303d list for sediment & degraded habitat, TMDL Approved in 2008. The Hardies Creek TMDL is a product of a partnership between the Wisconsin Department of Natural Resources (WDNR) and the Galesville-Ettrick-Trempealeau High School (GET) Science Department. In 2004, the WDNR provided funding, through a local water quality assistance grant to GET, to support supplemental data collection for the development of the TMDL. In coordination with WDNR field staff and under the direction of Mr. Jon Johnson (GET Science Teacher), students monitored habitat, macroinvertebrates, and water chemistry and assisted with fish electro-shocking in Hardies creek. Some of the information collected by students with WDNR supervision was used in the development of this TMDL.
This water was assessed during the 2014 listing cycle; biological sample data met 2014 WisCALM listing thresholds for the Fish and Aquatic Life use (i.e. macroinvertebrate or fish Index of Biotic Integrity (IBI) average scored in the fair to excellent condition categories).Pollutant
Sediment/Total Suspended Solids
Listed For
Fish and Aquatic Life
Impairments
Degraded Habitat
Current Use
Unsupported Aquatic Life
Listing Status
TMDL Approved
Attainable Use
Default - Fish and Aquatic Life
Priority
Not Applicable
Designated Use
Default - Fish and Aquatic Life
303(d) ID
34091-181
Listing Date
4/1/1998
Impaired Water Notes
The upstream portion of Hardies Creek (1.37 miles) that is not impaired, still had moderate streambank erosion, with a lateral recession rate of 0.2 feet/year. The mean eroded bank height in the portion of Hardies Creek that is not impaired ranged between 0.42 and 0.74 feet with a bank erosion sediment load of 14 lbs/ft/yr. The banks along this upper portion of Hardies Creek are less shaded and have vegetative ground cover that stabilizes the bank. Comparatively, the bank erosion sediment load along the impaired portions of Hardies Creek ranged between 45 and 87 lbs/ft/yr with eroded bank height
Final-Approved February 2008
8
generally exceeding one foot. The lower potion of Hardies Creek has more canopy coverage and less vegetative ground cover on the banks as reflected by the erosion width measurements.
The total existing sediment load contributed to Hardies Creek from streambank erosion calculations is approximately 2.6 tons per day. The target sediment load for the eroding streambanks is 0.79 tons per day for an overall reduction of 70% in Hardies Creek. A target recession rate of 0.1 ft/year was chosen for the entire stream, which falls in the middle of the NRCS ?moderate? erosion category: ?Bank is predominately bare with some rills and vegetative overhang. Some exposed tree roots but no slumps or slips.? It is expected that once streambanks are stabilized, there will be some naturally occurring erosion and a 0.1 recession rate reflects a reasonable target to achieve.
If the load reduction is sufficient to achieve the load capacity and the stream has not adequately responded, the load capacity will be reviewed and lowered appropriately. In the event that the stream adequately responds with a load reduction that is still above the load capacity, the WDNR will either pursue ?de-listing? of the stream or will revisit the load capacity.
Date
4/1/2008
Impaired Water Notes
The sediment TMDL for Hardies Creek was approved by the USEPA February 25, 2008.
Date
2/25/2008