Terrace Reservoir, reservoir in Conejos County, Colorado, United States

Terrace Reservoir is a water storage facility in Conejos County, Colorado, built in 1912 to hold water from the river and supply irrigation to farmland in the San Luis Valley. The earthen dam consists of two sections separated by a mountain ridge, with a large pipe directing flow into the Alamosa River.

The dam was built in 1912 as part of early water management efforts to support farming in the dry region. Starting in 2008, conservation teams began modernizing the system, and from 2015 onward, the reservoir actively works to provide water to the river during periods when flows would naturally drop.

The reservoir is owned by the Terrace Irrigation Company, which stores its water to irrigate crops in the San Luis Valley. The lake and the land around it form the Terrace Reservoir State Wildlife Area, where hunting and fishing take place. The name comes from the nearby settlement of Terrace.

The wildlife area is reached northwest of Capulin, within the Rio Grande National Forest, and the reservoir is owned by the Terrace Irrigation Company, so access to the water and dam structures can be restricted. The dam is split into two segments by a mountain in the middle; the spillway is on the northern segment and the outlet penstock on the southern one. Hunting and fishing are the activities the state wildlife area is designated for.

The dam is split into two segments with a mountain between them. The southern segment carries a penstock that drains the reservoir into the Alamosa River, while the spillway on the northern segment was replaced sometime after 2012. The structure carries National ID # CO00815.