Watershed Restoration Assessment for Lost Creek 

 — a tributary of the Upper Clark Fork River 



James A. Harris and Vicki Watson, 

 Environmental Studies, University of Montana, Missoula, MT 59812 



Lost Creek, a tributary to the Upper Clark Fork of the Columbia, is listed on Montana's 303(d) list as 

 impaired for a number of beneficial uses, including aquatic life support, drinking water supply, and cold 

 water fishery Lost Creek is undergoing major riparian restoration and grazing management changes which 

 will be the basis of a Total Maximum Daily Load (TMDL) for nutrients and sediment for the lower 17 

 stream miles Therefore the objectives of this project include the following 



1) assess current conditions in Lost Creek including kinds and degrees of impairment, 



2) provide baseline data to evaluate benefits of restoration work, 



3) evaluate Lost Creek as a nutrient source to the nutrient-impaired Clark Fork River, 



4) evaluate nutrient sources along Lost Creek, 



5) make recommendations for TMDL development for Lost Creek, and how it should relate to 

 the Clark Fork VNRP (which calls for a 20% reduction in nonpoint sources of nutrients) 



Water samples were collected from May through August 1 999 at sites along the creek which bracketed 

 suspected sources. Samples were analyzed for nutrients (nitrate/nitrite, total Kjeldahl nitrogen, soluble 

 reactive phosphorus, and total phosphorus) using an EPA-approved protocol Riparian health assessments 

 were performed on the lower 20 miles of Lost Creek using the University of Montana's Riparian and 

 Wetland Research Program's Lotic Inventory Form Riparian inventories are used to identify and prioritize 

 problem areas and provide detailed baseline information for gauging the success of restoration projects on 

 Lost Creek 



Lost Creek does not provide good habitat for attached algae growth, but in some areas aquatic plants may 

 be a problem Hence, the main reason for reducing nutrients in Lost Creek is to reduce the load to the Clark 

 Fork Phosphorus levels in Lost Creek were below those considered to be a problem for streams according 

 to the Clark Fork VNRP Total nitrogen (particularly nitrate/rutrite) levels are high enough to be a concern 

 Nitrate/nitrite levels increase in the area near Dutchman reservoir. Although wetland disturbance by cattle 

 grazing is a likely source of nutrients in this area, it appears likely that irrigation water from the land 

 application of Anaconda's municipal wastewater is leaching into groundwater from nearby hay fields and 

 from storage ponds in the Dutchman Creek drainage Riparian inventories found 30% of riparian areas were 

 not performing their functions while the other 70% were at risk to become nonfunctional. 



In terms of TMDL development for Lost Creek, the conservation practices being undertaken by landowners 

 with state and federal funding will likely improve habitat and reduce nutrient loads. Success should be 

 judged by periodic reevaluation of riparian condition and nutrient loads Lost Creek does provide a 

 significant TN load to the Clark Fork, and this is probably best addressed by riparian wetland restoration and 

 land application of Anaconda wastewater over a larger area at an appropriate agronomic rate. Additional 

 recommendations for monitoring and TMDL development are detailed in the full report 



This work was supported by the Montana University System Water Center with funds from the USGS 

 Section 104 Program Our grateful thanks to Montana Dept of Fish, Wildlife and Parks, the US NRCS and 

 landowners in the Lost Creek Basin for their efforts to restore Lost Creek 



