Little Cottonwood Creek TMDL
Albion Basin in Little Cottonwood Canyon
Little Cottonwood Creek is a 3rd order tributary of the Jordan River supporting: 1C - Primary drinking water supply, 2B - Secondary contact recreation, and 3A - Cold water fishery beneficial uses. "Portions of LCC located downstream from the Wasatch Drain Tunnel and upstream from the Baby Thunder Lift are predominantly B3 stream types, typified by moderately entrenched systems with channel gradients of 2 to 4 percent. These stream types typically develop in coarse alluvial fans, lag deposits, rockfall talus slopes, very coarse colluvial deposits, and structurally controlled drainage ways. They are dominated by cobble materials and characterized by a series of rapids with irregularly spaced scour pools" (U.S. Forest Service, 1999).
Instream Flow
Much of the annual streamflow in Little Cottonwood Creek results from snowmelt, producing higher flows around May, June and July of each year. Lower flows are experienced in late fall and winter. Precipitation and groundwater discharge also contribute significantly to the flow of Little Cottonwood Creek. Shallow rocky soils and steep canyon walls cause the creek's flow to be highly responsive to storm events (U.S. Forest Service, 1999). The Flood Control & Engineering Division of Salt Lake County monitors Little Cottonwood Creek flows on a daily basis at both Crestwood Park and 300 West. These records can be accessed through Salt Lake County Streamflow and Rainfall Historical Data.
Little Cottonwood Creek Water Quality
Historic mining activities have left behind numerous mine features (e.g. shafts, adits, mine waste dumps, mine drain tunnels, and access roads) that have had significant impacts on the beneficial uses of the creek. In 1994, the Utah Division of Water Quality (UDWQ) and Salt Lake City conducted a joint study of Little Cottonwood Creek. The results of their study indicate that the Creek had excess amounts of zinc from the Metropolitan Water Treatment Plant to the headwaters. They also found excess amounts of Total Dissolved Solids (TDS) from the confluence with the Jordan River to the Forest Service boundary. The suspected cause of high zinc levels was historic mining in the canyon. In 1998, Salt Lake County and UDWQ conducted additional studies that supported the initial findings. The Total Maximum Daily Load for Dissolved Zinc in Little Cottonwood Creek was published in 2002.
Little Cottonwood Canyon
Little Cottonwood Canyon is located in the Wasatch Mountain Range directly east of Sandy, Utah, ~25 miles from Salt Lake City. The canyon is in the Middle Rocky Mountains physiographic province and contains rock outcrops from the Precambrian and Paleozoic eras. Glacial features in the canyon include mountain spurs, cirques, scoured rocks, and moraines. Little Cottonwood Canyon soils are primarily rock-dominated and sandy loam units, which have developed on steep, recently glaciated terrain. These soils are generally thin and rocky, especially on the higher portions of the canyon (LCC TMDL, 2002).
TMDL Update
For a current update of the Little Cottonwood Creek TMDL, please visit http://www.waterquality.utah.gov/watersheds/jordan/tmdl_reports.htm#lcc.
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