Some algae, such as the filamentous greens, are conspicuous 

 and their excessive growth may be aesthetically displeasing, 

 deplete dissolved oxygen, interfere with fishing and fish 

 spawning, clog water filters and irrigation intakes, create 

 tastes and odors in drinking water, and cause other problems. 



PROJECT AREA AND SAMPLING SITES 



The project area is located in Park County near the city of 

 Livingston, Montana (pop. 7,414). Billman Creek heads west of 

 Livingston at Bozeman Pass (el. 5,760 feet) and flows easterly 

 for about 15 lailes to where it enters the Yellowstone River just 

 south of Livingston. For most of its length, Billman Creek 

 parallels Interstate Highway 90 and the main line of the 

 Burlington Northern & Santa Fe Railway. 



The Billman Creek watershed is within the Montana Valley and 

 Foothill Prairies Ecoregion (Woods et al . 1999). The surface 

 geology consists of upper Cretaceous volcaniclastic deposits of 

 the Livingston Group and lower Mesozoic calcareous sandstone, 

 shale, and limestone of the Ellis Group (Renfro and Feray 1972) . 

 Vegetation is mixed grassland on silty-clay soils (USDA 1976) . 

 Billman Creek is very different from most of the other small 

 streams in the area in that it has a mud bottom and flows through 

 agricultural land (Patrick Newby, MDEQ, personal communication) . 



Periphyton samples were collected at two sites on July 21, 

 2000 (Map 1, Table 1) . The upper site (Station 1) is located 

 just upstream of Miner Creek and the Cokedale Road, and about 5 

 miles upstream from the mouth of Billman Creek. The elevation of 

 this sampling site is about 4,900 feet. The lower site (Station 

 2) is located at the mouth of Billman Creek at an elevation of 

 about 4,500 feet. Billman Creek is classified B-1 in the Montana 

 Surface Water Quality Standards. 



