An IRRM is a series of temporary actions implemented by engineers designed to reduce the risk to downstream populations that may be associated with high water elevations at a USACE reservoir. Since 2017, a series of IRRMs have been implemented at Beaver Lake Dam. These IRRMs ranged from updated emergency action plans to water-proofing the operational equipment at the dam (gate controls) to faster, more effective evacuation of the water from the flood pool. Updating these flood pool evacuation operations was performed in a series of three steps, which are described below. 

• Minimum releases from Beaver increased from 950 cfs to 1,900 cfs when Beaver Lake is in flood pool and conditions downstream allow.

• Table Rock must be below elevation 917 feet

• Combined Beaver, Table Rock, and Bull Shoals less than 50 percent flood storage

2. Deeper Drawdown After Surcharge (release to prevent gates from overtopping).

• Drawdown of 1.0 to 1.5 feet from top of flood pool (from elevation 1,130.0 to 1290.0 or 1,128.5 feet depending on the time of year) after flood event

• Provides extra 0.5 to 0.75-inch runoff storage​

3. Revised Guide Curves at Newport and Georgetown.

Winter:

• Regulate to 24 feet stage at Newport

• Delay transition to springtime target stage by two weeks

Springtime:

• When system storage is LOW, use current low target (blue)

• When system storage is HIGH, use current high target (green dash), and

• When system storage is VERY HIGH, use current late springtime (May) target (red dots).

Summer/Fall:

• When system storage is above 30 percent, regulate to higher summer target (red dots).