From June 1987 to September 1988, water quality sampling was conducted on the Highland Bayou Diversionary Canal. Much data, including salinity, dissolved oxygen, and water temperature, was collected at 7 stations in the Bayou and from two wastewater treatment plants in order to detect differences between seasons, stations, and sampling depths. The trends were then used to assess impact of stresses on water quality. The water quality was strongly influenced by anthropogenic stresses. It did not suffer blooms of cyanobacteria or neritic organism kills characteristic of high eutrophic conditions, but increased population and urbanization may produce these conditions.