A Cedar Lake Augmentation Feasibility Study was completed in 2011. Based upon all evaluation criteria, which summarize the implementation feasibility of each source water option including cost-effectiveness, the following options appear to be most desirable and are therefore recommended for further implementation consideration. Prioritization of these recommended Cedar Lake augmentation options is as follows (- Cedar Lake Augmentation Feasibility Study, 2011, page 29):
1. King’s Corner culvert modifications (Refer to the Wetland Berm project)
2. Sherman/Jones Creeks modifications (Refer to the Sherman Creek In-Stream Grade Structures project)
3. Augmentation Well(s): Discharging to wetland
The CLIB continues to support an extensive groundwater and surface water monitoring network throughout the Cedar Lake watershed to track long term trends and impacts to hydrology resulting from watershed hydrology improvement projects.
1. Cedar Lake Wetland Berm Enhancement Project (Kings Corner Road) (2017):
This project restored hydrology and improved wildlife habitat of approximately 6-acres of source water wetlands in the watershed surrounding Sherman Creek (lengthening “wet season” flows) and involving up to 50 MG increase of seasonal flow volumes to the lake. The berm provides improved Sherman Creek/wetland fisheries spawning habitat with critical fish passage over existing conditions, contributes to decreased Cedar Lake water level fluctuations during summer months (with prolonged inflows and restored hydrology), and enhances and protects wetland habitat to improve pike fry maturation.
2. Sherman Creek In-Stream Grade Structures Project (2019):
The primary pathways for water loss from Cedar Lake are its outflow and evaporation. The lake typically outflows at a higher rate in the spring when inflows are at their highest. Modifying inflows such that they reach the lake at a lower flow rate and over a longer time span can reduce the amount of excess water that is lost as outflow in spring months and potentially delay the onset of lake level decreases during the summer months. In 2019, a series of in-stream grade structures were installed in Sherman Creek, the primary tributary on the western side of Cedar Lake. These structures increased the water storage volume in the attached wetlands and decreased flow rates to Cedar Lake, the combined effect of which is an increase in total flow to the lake as well as an increase in the flow duration, both of which mitigate lake level decreases.