OMAHA, Neb. -- The U.S. Army Corps of Engineers – Omaha District will conduct its annual sediment flushing exercise at the Cherry Creek Reservoir south of Interstate 225 in Aurora, Colorado, on May 22.
Katie Seefus, water manager, USACE, says the exercise involves high releases from each of the five main outlet gates.
"When the gates are opened, the high velocity of the water leaving the reservoir scours the area immediately upstream of the gates and transports sediment with the flow," Seefus said. “This sediment flush is required to allow proper operation of the outlet gates.
Cherry Creek Dam will begin releasing 50 cubic feet per second (cfs) at 2:30 p.m. on Tuesday, May 21. The actual flushing exercise will begin at 9:00 a.m. and end at 12:30 a.m. on Wednesday, May 22, when the release will be set back to normal levels. The travel time from Cherry Creek Dam to the stream gauge located at the Champa Street Bridge, is approximately six hours.
Omaha District Commander Col. John Hudson asks the public to be aware that the high flows will take some time to reach the downtown channel, and flows from the last gate opened will not reach the downtown channel until Wednesday evening. The high flows will cause higher than normal creek stages and potential flooding of bike paths and stream crossings.
"In the interest of public safety, I urge the public not to attempt to cross the stream during this event," Hudson said.
The following table shows a schedule of the planned releases:
| TASK |
TIME |
| Gate 1 release 250 cfs |
9:00-9:15 a.m. |
| Gate 1 closed |
9:15-9:20 a.m. |
| Gate 2 release 250 cfs |
9:20-9:35 a.m. |
| Gate 2 closed |
9:35-9:40 a.m. |
| Gate 3 release 250 cfs |
9:40-9:55 a.m. |
| Gate 3 closed |
9:55-10:00 a.m. |
| Gate 4 release 250 cfs |
10:00-10:15 a.m. |
| Gate 4 closed |
10:15-10:20 a.m. |
| Gate 5 release 250 cfs |
10:20-11:20 a.m. |
| Gate 5 release 100 cfs |
11:25-12:25 a.m. |
| Gate 5 closed |
12:25-12:30 p.m. |
| Gates set to normal levels |
12:30 p.m. |
Release no. 19-071