Pella Chronicle

October 22, 2012

Ask the Corps

Sherri Duey
Operations Manager Lake Red Rock

Pella — As of this writing on October 11, the elevation of Lake Red Rock has dipped below its normal conservation pool of 742.00 mean sea level (msl).  In the reservoir’s history, this has only occurred twice before:  In February 1977 and in February 1988. While the difference between the lake’s normal conservation pool and the current lake level is less than ½ foot, there is the potential to go lower if drought conditions continue.   

In recent flood years, people became familiar with Lake Red Rock’s role to reduce flood risks along the Des Moines River and Mississippi River; however, the lake is also authorized by Congress for a job on the opposite end of the spectrum called “low flow augmentation.”   The reservoir’s water stored for this purpose is used to provide additional water flow in the Des Moines River below the dam.   Current inflows into Lake Red Rock are less than outflows from the dam, and the lake level will continue its slow drop in elevation until more precipitation changes that.  

Each fall, the Iowa Department of Natural Resources is authorized to request a two-foot lake raise for waterfowl migration; however, there is not enough water in the system to accomplish the raise this year.  Boaters using upstream portions of the lake should use caution due to shallow conditions and mudflats.

For more information, contact the Corps office at (641) 828-7522 or (641) 628-8690.