Halfmoon Lake is near the end of a seven-chain lake that drains toward the Huron River. The lake is approximately 236 ac (95 ha) in size with channels that connect to Watson Lake, Blind Lake, and Hiland Lake. As described in a 1992 MDNR report, “The lake bottom consists primarily of marl in the shallow water areas and muck and pulpy peat in deep water. There are also scattered areas of fibrous peat, gravel, rubble, and sand which are found mainly in the shallows. Halfmoon Lake has steep drop-offs, several submerged islands, and water depths up to 87 feet.”

Water levels on Halfmoon Lake can fluctuate due to precipitation changes and seasonality. However, they are also influenced by the Hiland Lake dam which is maintained by the Livingston County Drain Commissioner’s Office. The legal lake level of Hiland Lake is court ordered, and the structure has been maintained and operated in accordance with Part 307 and Part 315 of the Natural Resource and Environmental Protection Act and Act 451 of 1994. There is a staff gauge located at the dam where the dam operator monitors the Hiland lake level.

The 70 sq mile (181 sq km) Patterson Lake watershed feeds the chain of lakes and provides the primary surface water inputs to Halfmoon Lake. The watershed for Hiland Lake is approximately 77 sq mi (200 sq km) and includes a mix of residential and natural areas.

The Michigan DNR completed a fisheries survey of Halfmoon Lake in 1992 with results available here.

The area where the lake water meets the land is a critically important component of the lake ecosystem. Halfmoon Lake has a suite of shoreline types including wetland, beach, rocks, and steel. Softened shorelines (e.g., rocks, plants) provide fish and wildlife habitat while limiting erosion in front of lakeside houses. Existing steel and vinyl sea walls can be improved (from the lake’s perspective) by adding rocks, plants, and other features on the lake side to dissipate wave energy and create nooks and crannies for critters. There are many examples of softened natural shorelines around the lake, so reach out to the HLCA if you would like to see what others have done.