Non-point source pollution ranks as the largest single impairment to water quality in the United States with Agriculture being the leading source (USEPA, 1997). Best Management Practices (BMPs) have been designed and adopted in an effort to reduce surface and ground water contamination from Agricultural sources. The Owl Run watershed was monitored for a period of 10 years, including 2.5 years of extensive monitoring prior to establishing BMPs. Several BMPs were established in targeting better management of animal waste these included: conversation tillage, field strip cropping, grassed waterway and alternative livestock water sources. Water samples were collected on a bi-weekly basis and analyzed for feacl coliform anf fecal streptococcus bacteria.

Mean fecal coliform bacteria were reduced by 40% at the waterrshed outlet with the implementation of BMPs. However, all sub-watershed stations indicated increases in overall fecal coliform levels from 9% – 94% during the post-BMP period. Fecal streptococcus bacteria were reduced by 80% at the watershed outlet, with the sub-watersheds experiencing reductions between 59% – 69%. The fecal coliform to fecal streptococcus bacteria ratio was applied to the watershed as an indictation of the source of pollution. Throughout the duration of the experiment, pre and post-BMP phases has ratios that indicated domestic animal were the principal cause of feacl pollution. Reductions in bacteria levels were also citied during the winter months with the implementation of the BMPs. This reduction can be explaned through the storage of manure throughout winter months, increasing the flexibility in timing of land application. Increases in the spring are most likely due to the more intensive application of manure throughout that period.