LITTLE ROCK, Ark. -- The U.S. Army Corps of Engineers Little Rock District plans to conduct a hinged pool operation in the Dardanelle Pool of the Arkansas River from approximately Thursday, July 10 through Thursday, July 17, as part of a targeted effort to improve navigability and reduce future maintenance dredging needs.
This short-term operation will temporarily lower the Dardanelle Pool water level by about half a foot, from elevation 337.0 to 336.5 feet (NGVD29), and hold it steady for several days to promote natural scouring of a troublesome shoaling area near Navigation Mile 221.4, between Russellville and Ozark. River flows are forecasted to decrease from approximately 175,000 cubic feet per second to 80,000 c.f.s during the operation, allowing the river’s energy to help flush sediment from the channel.
The public may notice slightly lower-than-normal water levels in backwater areas along the river during this time. This is a planned and temporary condition, and river traffic and hydropower operations at Dardanelle Lock and Dam are expected to continue throughout the operation.
By taking advantage of the current high flow conditions and executing a controlled pool adjustment, we aim to reduce future dredging needs and improve navigation safety in a historically problematic section of the river,” said Aaron McGee, Operations Project Manager for the McClellan-Kerr Arkansas River Navigation System.
The hinged pool technique has been used successfully in the past but has not been employed at Dardanelle for more than 25 years. Shoaling and sediment buildup in this section of the river have significantly increased in recent years, including a grounding incident involving a navigation vessel on June 11.
USACE coordinated closely with stakeholders including the Southwestern Power Administration, Entergy’s Arkansas Nuclear One facility, the Arkansas Game and Fish Commission, and others to ensure awareness and minimize impacts.
Start and end dates for the operation are subject to change based on rainfall, runoff, or adjustments in upstream floodwater releases. The USACE will continue to monitor conditions and provide updates as needed.
Recreation information can be found on the Internet at www.swl.usace.army.mil, on Facebook at www.facebook.com/littlerockusace and on the USACE Little Rock water level mobile app at www.swl.usace.army.mil/Home/water-control-app/.