The construction of the dam was given impetus by the Great Flood of 1951, which inundated downtown Manhattan. Nevertheless, the project met with heavy opposition from landowners whose land faced flooding. When the lake began filling up in 1962, it affected ten towns and entirely submerged many of them. The only one of these submerged towns to rebuild elsewhere was Randolph, where many of the streets are named after other towns that were submerged. The remnants of "Old Randolph", as it's known locally, can still be seen partially submerged to this day.
The value of the dam was proven during the Great Flood of 1993, when floodwaters reaching up to 63 feet (19 m) above normal were held back. However, when the dam reached capacity in July 1993, it necessitated the first release of the spillway. All 18 gates on the spillway were raised 4 feet (1.2 m) during the peak of the flood, producing a flow rate of 60,000 cubic feet per second (1,700 m³/s). The roar of the water was audible half a mile (800 m) away and some people in nearby Manhattan reported hearing the noise. After three weeks the gates were closed, revealing a 20-foot deep canyon that had been carved in the earth of the spillway channel. The exposed rock is 290 million years old. Locally, this area is known as "The Canyon" and is a popular fossil-hunting area.
Although Kansas is not widely known as seismically active, the Humboldt fault line associated with the Nemaha Ridge passes through eastern Kansas, and probably the most active region on the line is in the general vicinity of the lake. It was recently determined that the geology of the area could potentially produce an earthquake capable of causing the dam to fail, which could risk the lives of thousands downstream in the Blue River and Kansas River valleys. The Army Corps of Engineers has started a project to strengthen the dam sufficiently to withstand such a quake. They have also established an interim warning system.
Tuttle Creek Lake, in the Big Blue River valley just north of Manhattan, is surrounded by the wooded valleys and tallgrass prairie uplands of the Flint Hills. At the northern end of the lake is the wildlife area, where migrating waterfowl and shorebirds can be seen in fall and spring. The best sites for viewing prairie wildlife are the Kansas State University Range Research Unit (2 miles southwest of the dam) and along Prairie Parkway (west of K-13), east of the lake. The most accessible and probably best all-around viewing area is River Pond State Park below the dam.
Here along the river, gadwall and common goldeneye ducks along with common mergansers and ring-billed gulls are abundant in winter. On occasion long-tailed ducks and common loons are sighted. In mid-winter bald eagles fish the river pond and perch on the tall trees of Eagle Island. East of the outlet channel, ponds support beaver and muskrats year-round and American wigeons and northern shovelers in winter. Listen for western chorus frogs in March and April and bullfrogs and cricket frogs in summer.
During migrations, watch for warblers, sparrows, and ospreys. Herons are often seen in summer. In the grasslands along Prairie Parkway you can see upland sandpipers as well as loggerhead shrikes and western kingbirds perched on fence posts. Eastern meadowlarks, dickcissels, grasshopper sparrows, and mourning doves are also frequently seen. On the Range Research Unit, greater prairie chickens boom in the pre-dawn light of April and May. A couple of miles west of Stockdale Cove, on private land along Mill Creek, tall sycamores hold large stick nests of great blue herons.