An intensive water quality survey of stream cattle access sites
As part of an investigation of the relative importance of rural diffuse pollution sources in the Avon River basin, the Stratford-Avon River Environmental Management Project (SAREMP) conducted a pilot study in 1982 of the impacts of livestock on water quality at cattle access sites. Five sites were chosen on the basis of the following criteria: intensity of in-stream livestock activity, variability in length and type of access, accessibility for field work, and good farmer cooperation. Water chemistry and bacterial inputs were studied during both dry and wet weather conditions, in conjunction with physical site characteristics and livestock activity in or near the stream channel. During the summer grazing season livestock activities at or near the stream had a detrimental impact on the downstream water quality. Substantial increases in nutrient and bacterial loadings occurred as a direct result of in-stream cattle activity during the dry weather survey. Wet weather impacts observed in this study were limited to large increases in bacterial contamination at the cattle access site. Detection of Pseudomonas aeruginosa during the storm event indicated that direct human waste inputs may also be responsible for the elevated background levels of bacteria.