Coralville Lake
Coralville Dam on June 15, 2008, with the main control gates fully opened, and water flowing over the concrete emergency spillway (left) at about 5 ft (1.5 m) deep
Coralville Lake
Location	Johnson County, Iowa, U.S.
Coordinates	41°43′28″N 91°31′47″W / 41.72444°N 91.52972°W / 41.72444; -91.52972
Type	reservoir
Primary inflows	Iowa River
Primary outflows	Iowa River
Catchment area	Upper Mississippi River
Basin countries	United States
Water volume	461,200 acre⋅ft (568,900,000 m3)

Coralville Lake is an artificial lake in Johnson County, Iowa, United States, formed by the Coralville Dam, a dam built from 1949 to 1958 on the Iowa River upstream from the city of Coralville, Iowa.

History

Coralville Dam
Country	United States
Location	Johnson County, Iowa
Status	Operational
Construction began	1949; 75 years ago (1949)
Opening date	1958; 66 years ago (1958)
Construction cost	$15,744,000
Owner(s)	U.S. Army Corps of Engineers
Dam and spillways
Type of dam	Earth Filled Embankment
Impounds	Iowa River
Height	100 ft (30 m)
Length	1,400 ft (427 m)
Width (crest)	22 ft (7 m)
Width (base)	850 ft (259 m)
Reservoir
Creates	Coralville Lake
Total capacity	28,100 acre⋅ft (34,660,840 m3) (Normal pool); 421,000 acre⋅ft (519,295,854 m3) (Flood storage pool)
Catchment area	3,084 sq mi (7,988 km2)
Surface area	5,280 acres (2,140 ha) (Normal pool); 24,800 acres (10,000 ha) (Flood storage pool)
Maximum length	23 mi (37 km) (Normal pool); 41.5 mi (67 km) (Flood storage pool)
Normal elevation	679–717 ft (207–219 m) above msl
Website http://www.mvr.usace.army.mil/Missions/Recreation/Coralville-Lake/

After widespread flooding in the United States during the early 1930s, Congress passed the Flood Control Act of 1938. The United States Army Corps of Engineers built the 100-foot-high earthen dam primarily as a flood control project for the Mississippi River. Construction started in 1949, was delayed by the Korean War, and was completed in 1958.^[1]

The lake has a capacity of 461,200 acre⋅ft (568,900,000 m³) of water, equal to 137.18 billion gallons at its "100 year flood" level of 712-foot (217 m).^[2]: 2

Floods

Water first flowed over the 712-foot (217 m) emergency spillway on July 5, 1993 (see Great Flood of 1993), reaching a then-record crest.^[2]: 2 This flood uncovered what is now the Devonian Fossil Gorge.^[1]

The 1993 record was surpassed by the June 2008 Midwest floods,^[3] when water again flowed over the 712-foot (217 m) emergency spillway on June 12, 2008, and the reservoir crested at 717 feet (219 m) early in the morning on June 15, 2008.^[4]

Lake Macbride is formed by another dam just up from the Coralville reservoir. This dam was overtopped by floodwaters in the flood of 2008, and the lake effectively became part of Coralville Lake.^[5]

Recreation and public use

The lake and surrounding shoreline have been extensively developed for public recreational use, including hiking, biking, camping, fishing and boating.^[6] There are 11 recreation areas, 4 swimming beaches, 3 marinas, 18 boat ramps, 3 campgrounds (total of 620 campsites), 7 large picnic shelters, 2 disc golf courses, and 7 trails (total of 29 miles).^[7]

Photos

• 
  Coralville Dam and Reservoir near Coralville, Iowa.
• 
  A tackle shop near Coralville Dam.
• 
  Coralville Lake as seen from the airplane during winter