Authorized: Flood Control Act of 1958

Construction: 1965-1977; $130 million

Dam:

• Type: Earth Filled Embankment
• Length: 6,750 feet
• Height: 105 feet
• Top Width: 44 feet
• Elevation (Top of Dam): 915.5’ National Geodetic Vertical Datum (NGVD) 29

Reservoir: 8 Miles North of Des Moines, IA

Normal Pool:

• Length: 19 miles
• Area: 4,970 acres
• Storage: 64,650 acre ft. (21.1 billion gallons) ¹

Flood Storage Pool:

• Length: 54 Miles
• Area: 15,990 acres
• Storage: 626,465 acre ft. (204.1 billion gallons)

Water Surface Elevation:

• Normal Pool: (11.5% of total storage capacity) 836’ NGVD29
• Flood Storage Pool: A rise of 54’ in elevation 890’ NGVD29 (Top of Pneumatic Crest Gates)

Watershed Above Dam: 5,823 square miles

Total Project Acres: Approximately 26,000

Authorized Missions: Flood Risk Management, Recreation, Environmental Stewardship, Water Supply, Low Flow Augmentation

Recreation:

Visitation FY22: 2,187,245 Visitors (estimated)

Corps Recreation Areas:

• Campgrounds: 4 with 530 campsites available
• Boat Ramp Access: 3 areas with 12 launch lanes
• Day Use Areas: 13 (including 24 group shelters)
• Beaches: 1
• Visitor Center: 1
• Marina: 1 (Leased to Private Company)

Environmental Stewardship Lands:

Wildlife/Forest/Prairie Management: 14,836 acres

Water Supply: Water supply storage contract with the State of Iowa
 

Regional Economic Impact: $57 million (FY22)

Flood Damages Prevented: $494 million (2022 $)

Average Inflows: 6,000 cubic feet per second (cfs) ²

Average Outflows: 7,200 cfs

Historical:

Highest Inflows Recorded:

• 60,600 cfs -  June 10, 2008
• 47,100 cfs -  July 11, 1993

Highest Outflows Recorded:

• 47,000 cfs -  June 12, 2008
• 44,500 cfs -  July 18, 1993

Record High Pool Elevations:

• 892.03’ NGVD29 (July 11, 1993)
• 891.03’ NGVD29 (June 12, 2008)
• 889.25’ NGVD29 (June 22, 1984)
• 889.15’ NGVD29 (July 1, 2010)

Spillway Releases:

• July 1, 2010 (7 Days)
• June 10, 2008 (12 Days)
• June 18, 1993 (42 Days)

¹NOTE: An acre-foot is one acre of water one foot deep. One acre foot is equivalent to 325,851.4 U.S. gallons.
²NOTE: Cubic feet per second (cfs). The rate of flow past a given point, measured in cubic feet per second. One cubic foot of water equals about 7.5 gallons and weighs 62 pounds.