Approximately 77% of the Sleeman River catchment has been cleared and is now dominated by grazing and cropping. Extensive clearing along the main channel has reduced the Sleeman to not much more than an agricultural drain. It has been straightened and channelled in sections, and is periodically cleaned out.

The River has a mean annual flow of 11.3 million cubic metres per year and past studies have shown contributes large amounts of nutrients to the Wilson Inlet.

The sites were sampled in September 2007.

Western Minnow, Night Fish, Western Pygmy Perch and Shrimp were recorded at both of the sites. SLE01 also recorded Gobies, tadpoles and feral species Gambusia and Yabbies. SLE02 also recorded fresh water crayfish species Cherax crassimanus. Pictures of these can be viewed in the gallery.

Both sites on the Sleeman River were consider to be slightly degraded.

The Sleeman River is a fresh water (0.9mS/m) and neutral (6.3pH) system.

Site SLE01 recorded a very high level of turbidity, total phosphorus and total nitrogen. SLE02 recorded a high level of turbidity and moderate levels of total phosphorus and nitrogen.