Griffy Lake

Griffy Lake
The dam drain of Griffy Lake
Location	Bloomington, Monroe County, Indiana, United States
Coordinates	39°12′00″N 86°32′00″W / 39.20000°N 86.53333°W / 39.20000; -86.53333Coordinates: 39°12′00″N 86°32′00″W / 39.20000°N 86.53333°W / 39.20000; -86.53333
Type	reservoir
Primary inflows	Griffy Creek
Primary outflows	Griffy Creek
Basin countries	United States
Surface area	109 acres (44 ha)
Water volume	1,280 acre·ft (1.58 hm3)
Surface elevation	633 ft (193 m)
Settlements	Bloomington

Griffy Reservoir, commonly known as Griffy Lake is a water reservoir in the city of Bloomington, Indiana. Created by a dam on Griffy Creek in the 1920s, the reservoir used to serve as the main source of drinking water for Bloomington for several decades, until that role was taken over by the larger Lake Lemon and Lake Monroe in the 1950s.

A large part of the lake's forested watershed is designated as the Griffy Lake Nature Preserve (GLNP). Another part of the watershed is included into Indiana University's Research and Teaching Preserve as its Griffy Woods section. Griffy Woods includes a smaller reservoir, known as the University Lake, which in a sense was a predecessor of Griffy Lake, and is part of the latter's watershed.

In the early 20th century, to satisfy the needs of the growing city and Indiana University, the city of Bloomington constructed a number of dams on various tributaries of Clear Creek southwest of town, creating a number of reservoirs: the Leonard Springs Reservoir, Wapehani Lake, Twin Lakes. However, due to the Mitchell Limestone subsoils in the area, these reservoirs continuously leaked water, making it impossible to reliably supply the city, and in particular the university, with the water they needed.

Unable to receive the necessary amount of water from the city's leaky reservoirs, Indiana University's Board of Trustees in 1909 decided to undertake its own reservoir construction. University President William Lowe Bryan formed a committee led by geology professor E.R. Cumings, which on March 8, 1910, recommended a site for the new reservoir, which is now known as the University Lake. The E.R. Cumings' recommendation, the dam for the new reservoir was constructed over impervious Knobstone formations, blocking a ravine of a small tributary of Griffy Creek northeast of the IU campus. Griffy Creek is a tributary of Beanblossom Creek, which in its turn flows into the West Fork of Indiana's White River.

The 40' tall concrete arched dam of University Lake was constructed in several stages between 1910 and 1914.