Lake Isabel
The lake and spillway in 2018.
Lake Isabel Location in Colorado
Location	Pueblo County and Custer County, Colorado
Coordinates	37°59′05″N 105°03′09″W / 37.9847°N 105.0526°W / 37.9847; -105.0526
Type	reservoir
Primary inflows	Saint Charles River
Primary outflows	Saint Charles River, evaporation
Basin countries	United States
Surface area	35.7 acres (14.4 ha)[1]
Water volume	969.8 acre-feet (1,196,200 cubic meters)[1]
Surface elevation	2,585 meters (8,481 feet)[2]
Frozen	The lake freezes in winter and ice-fishing is possible.

Lake Isabel is a reservoir located in the San Isabel National Forest in Pueblo and Custer counties, in Colorado, United States. The lake is in the Wet Mountains.^[3] The lake is open to fishing year round and is regularly stocked by Colorado Parks and Wildlife. Available activities include fishing, hiking, camping and sledding in the winter.^[4]

The community of San Isabel lies on the north side of the lake, in Custer County. The border between Pueblo and Custer counties runs north–south through the east side of the lake, such that most of the dam is in Pueblo County (on the east side), and most of the reservoir itself is in Custer County (on the west side).

The earthen dam and reservoir were built in the 1930s to store water for the CF&I Steel plant in Pueblo.^[1] Now the lake and the area surrounding it are managed by the United States Forest Service as the Lake Isabel Recreation Area.^[5]