Two of the main tributaries of Mona Lake, Little Black Creek and Black Creek, are impaired due to sedimentation. Sedimentation is a buildup of sand and fine organic particles. This usually results from sediments (soil particles) eroding from construction sites, streambanks, and cropland. Sediments can cause the water to become cloudy, shallow, and warm. They also cover spawning habitat for fish and fill in wetlands that are breeding grounds for ducks.

Road/stream crossings are a common suspected source of sedimentation because of the tendency for erosion around culverts and bridges. There were 125 road/stream crossings identified in the Mona Lake watershed and they are each being inventoried to see if any problems exist.

Additional sources of sediments are streambank erosion, dumping of leaves/lawn clippings, farm field runoff, and even sewage spills. During the Mona Lake Watershed Council's field inventory work, some of the following photos were taken. These are all sources of sediment that need to be addressed through implementation projects.

Ditch maintenance work in Black Creek
Black Creek Ditch Maintenance

Streambank erosion along Little Black Creek
Little Black Creek Streambank Erosion

Road / Stream Crossing
Road / Stream Crossing