John Martin Reservoir is a state park and a flood-control dam at the same time

John Martin Reservoir, east of Las Animas, does two jobs at once.

It is a federal reservoir, built and run by the U.S. Army Corps of Engineers’ Albuquerque District, that holds back the Arkansas River for flood control and stores water for irrigation downstream. The water level can swing a lot from season to season and year to year, because the reservoir is managed for those jobs first, not for recreation.

It is also a Colorado state park, run by Colorado Parks and Wildlife. People come for fishing, boating, camping, and birdwatching, and the area sits along the Arkansas River corridor that draws a wide range of birds to the plains.

For a visitor or a nearby buyer, two things are worth keeping in mind. First, like other Colorado state parks, entry requires a pass, and the rules and seasons are set by CPW. Second, because the reservoir rises and falls for flood control, the shoreline and boat ramps you see one summer may look different the next.

For current park hours, passes, water conditions, and what is open, check the Colorado Parks and Wildlife page for John Martin Reservoir State Park. For the dam itself and its flood-control job, the official source is the Army Corps of Engineers’ Albuquerque District.