Understanding Big Gull Lake Dam
Big Gull Lake Dam is a water control structure that is located at the outlet of Big Gull Lake. The Big Gull Lake Dam is a concrete structure consisting of two sluices and an overflow weir, and is owned and operated by MVCA. The sluices have different configurations with the north sluice containing seven 0.25 m x 0.30 m x 2.90 m stoplogs and the south sluice containing five, 0.25 m x 0.30 m x 2.29 m stoplogs. Although the dam has an overflow weir, water levels rarely get to its top height of 253.66 m. Big Gull Lake dam has a drainage area of 135 sq km, a total storage volume of 3,048 ha m, and a usable storage capacity of 2,286 ha m.
Seasonal Management Strategies
As this is a headwater lake with minimal concerns of flooding residential buildings, it is extremely important to capture all spring runoff early to ensure reaching the summer target level of 253.40 m.
Lake levels are targeted to an elevation of 253.10 m prior to the start of walleye spawning.
Lake levels are targeted between 253.30 m and 253.50 m throughout the summer months with virtually no flow being passed through the dam at elevations below 253.40 m.
The fall drawdown begins after Thanksgiving weekend with 8 of the 12 stoplogs (4 from each sluice) removed during this process.
Lake levels are targeted to drop to around 252.60 m by December.