Temescal Creek drains into the marshes near the Emeryville–Oakland border on the eastern midpoint of the marshlands. The wetlands are made up of native species of pickleweed, and are currently being threatened by Spartina, a non-native invasive species of Cordgrass. It has invaded 2.4 acres (0.97 ha) or 2.5% of the wetlands. There is an active abatement program consisting of aquatic herbicides.
The park is often used as a recreational area by local fishers and dog-walkers. The reserve is also noted for various problem areas such as unauthorized camping, petty littering, and dumping large articles of garbage such as TVs and refrigerators.