MANHATTAN, Kan. — Heavy upstream runoff has triggered a massive surge of water into Tuttle Creek Reservoir, pushing the lake completely through its normal conservation limits and forcing it to begin absorbing floodwaters.
According to data collected early today, the reservoir’s elevation jumped a dramatic 2.69 feet in just 24 hours, reaching 1,087.04 feet. That increase represents an additional 48,004 acre-feet of water entering the lake in a single day.
The spike is being driven by torrential inflows from the Big Blue River, which was clocked at a staggering 23,000 cubic feet per second (cfs) at 7:00 AM—an increase of more than 18,300 cfs from the previous day. To help mitigate potential downstream flooding, officials have kept outflows from the dam restricted to a minimal 1,000 cfs.
Because of this strategy, Tuttle Creek has officially filled 100% of its normal conservation storage space and has now tapped into 7% of its dedicated flood storage capacity. The lake currently holds a total of 433,780 acre-feet of water.
Flood Warnings Active Upstream
The sudden influx of water has caused significant issues in surrounding Marshall County, where emergency officials are monitoring two major rivers currently pushed past their banks:
- The Big Blue River (near Blue Rapids): Under a Flood Warning after breaching its 26-foot flood stage. The river was measured at 28.1 feet at 8:15 AM and is expected to crest at 29.1 feet this afternoon before finally dropping below flood stage late tomorrow evening.
- The Black Vermillion River: Also under a active Flood Warning. As of 1:30 PM today, the river had risen to 21.7 feet (above its 19-foot flood stage). It is projected to hit a crest of 24.5 feet this evening, though it is expected to recede quickly and fall below flood stage late tonight.
Hydrologists caution that these crest forecasts are based on current conditions, and any additional rainfall over the basin could quickly alter river projections and force changes to the reservoir’s management strategy. Local residents in low-lying areas are urged to stay weather-aware.
