Located in the upper watershed, Chester Morse Lake is impounded by the masonry dam and a secondary control structure called the Overflow Dike.

The surface of Chester Morse Lake has an average annual fluctuation of about 20 feet in elevation.

Inundation of the Cedar and Rex river deltas strongly affects their aquatic and wetland habitats.

Inundation of the Cedar and Rex river channels within and upstream of the delta causes sedimentation that can negatively affect bull trout eggs.

A population of kokanee (a landlocked form of sockeye salmon) lives in Walsh Lake and spawns in its major tributary, Webster Creek.

The water levels of 14 Lakes fluctuate seasonally and inter-annually based on the amount of precipitation and rates of groundwater inflow and outflow.