Lake Francis Case, SD

As of 2026-10-12, Lake Francis Case sits at 50.31 ft, which is below average for this time of year. Over the past 30 days the level has fallen 5.22 ft.

The most recent reading at Lake Francis Case is 50.31 ft (2026-10-12), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.

The highest level for Lake Francis Case in our records is 74.93 ft on 2011-07-08. The lowest is 44.10 ft on 1992-11-29. Our record covers about 37 years of readings.

Compared with every October in our records, the current level is higher than 34% of them, which we classify as below average for this time of year. Seasonal comparison matters more than the raw number, because most reservoirs draw down predictably through late summer and refill over winter and spring.

Reservoir levels move for four main reasons: rainfall and runoff into the basin, releases through the dam for downstream water supply, power generation or flood control, evaporation during hot months, and seasonal drawdown schedules set by the operating agency. Lake Francis Case has fallen 5.22 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.

Lake Francis Case is -3.97 ft compared with this date last year (50.31 ft today). The full-history chart above covers 37 years, with a record high of 74.93 ft and a record low of 44.10 ft.