| Abstract/Description or Keywords |
The health of Joseph Creek, which runs through the City of Cranbrook was reviewed using the results of benthic invertebrate and water quality monitoring from 2007 to 2012. This study reviewed three sites in the watershed: 1) NGJOS01, an upstream site which represented undeveloped conditions; 2) NGJOS02, a mid stream site, representing urban conditions, and; 3) a NGJOS03, a downstream site, representing semi-rural conditions. Overall, the study determined that Joseph Creek became increasingly impacted progressing downstream. The site in the upper watershed (NGJOS01) was found to be unstressed in all years when the benthic macro-invertebrate communities from test sites were compared to reference condition sites. NGJOS02 was found to be unstresssed in one year (2011), all other years were either potentially stressed or stressed. NGJOS03 was stressed in all but one year, when it was potentially stressed. The CABIN assessments were supported by other macro-invertebrate analyses and metrics, including: ratios of observed to expected taxa, presence of pollution intolerant taxa (Ephemeroptera, Plecoptera, and Trichoptera), presence of pollution tolerant taxa (Chironomidae), and proportions of dominant and first two dominant taxa. Water quality analysis showed few guideline exceedances but the majority of these occurred at the site furthest downstream (NGJOS03). Guidelines were exceeded for total phosphorus, dissolved oxygen, aluminum, and turbidity. Turbidity levels were elevated compared to guidelines at NGJOS03 at both clear flow and turbid flow times of the year. Differences in the thermal conditions were observed between sites, with little interannual variation. The greatest difference was found to be between NGJOS01 (upstream site) and the other two sites. Temperatures at both NGJSO02 and NGJOS03 were above the optimal temperature for westslope cutthroat trout and bull trout rearing during the warmer portions of the year. |
