The effects of the input from a small sewage plant and a feedlot on a small drainage ditch were investigated. Primary parameters used in the study were bacterial numbers and type, chemical forms of nitrogen, phosphate and dissolved oxygen. Originally, it was planned to use chemical assays and bacterial typing to identify the source of various pollutants. Success was partial. It was found that the feedlot contributed both kjeldahl nitrogen and nitrate to the drain. No phosphate contribution was detected. Oxygen levels were unaffected by the feedlot except after storm runoff. The feedlot runoff after heavy rainfall was very high in nitrate, kjeldahl nitrogen, phosphate and BOD. During the dry time of the year, significant amounts of ammonia were released. Microbial studies were difficult to assess due to high levels associated with agricultural drains. These drains also interfered with chemical studies because of high background levels of pollutants.

PROJECT NO. A-054-NMEX