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Imperial Refuge Wilderness

General Location Maps Contacts Area Management Wilderness Laws Trip Planning
Photograph taken in  the Imperial Refuge Wilderness


The United States Congress designated the Imperial Refuge Wilderness (map) in 1990 and it now has a total of 15,056 acres. Arizona contains approximately 9,220 acres. California contains approximately 5,836 acres. It is managed by the Fish and Wildlife Service. The Imperial Refuge Wilderness is bordered by the Indian Pass Wilderness to the west, the Little Picacho Wilderness to the south, and the Trigo Mountain Wilderness to the east.


You might be surprised to find a lush river ecosystem in the midst of the Sonoran Desert, the hottest and driest in the United States, a land of prickly cacti and specially adapted plants and animals. But that's exactly what you get in this Wilderness. The lower Colorado River, the boundary between California and Arizona, has many backwater lakes varying in size from one-half acre to 700 acres. Here, the Imperial Refuge Wilderness was established within the Imperial National Wildlife Refuge to preserve all forms of life found in the lower Colorado River region. The Wilderness stretches along both sides of the river in Arizona and California. A portion of the Wilderness also extends into Arizona.

When enough rain falls the desert bursts into stunning bloom: yellow paloverde, lavender smoke trees and ironwood, pink beavertails, red prickly pears, and purple and gold bellyflowers (so named because you must lie on your belly to appreciate these small blossoms). Mule deer come to drink from the river beside great blue herons while desert bighorn sheep watch from multihued hills nearby. Gambel's quail are ubiquitous, and wild burros can be seen from time to time. Resident and migratory birds are abundant. Beavers inhabit the waters, which may contain a few of the endangered Colorado squawfish--sometimes known to reach five feet in length.

Backwater lakes attract anglers who fish, typically with great success, for largemouth and striped bass. With a canoe you can put in at the upper boundary for easy paddling down to Martinez Lake Marina at the lower end. Because no overnight camping is allowed in the Wilderness, you'll have to camp at Picacho State Recreation Area on the California side. Hikers who wander into the Wilderness must carry plenty of water, a map, and a compass; each year, a few careless visitors get into jams that result in costly search-and-rescue operations.

Planning to Visit the Imperial Refuge Wilderness?

Leave No Trace

How to follow the seven standard Leave No Trace principles differs in different parts of the country (desert vs. Rocky Mountains). Click on any of the principles listed below to learn more about how they apply in the Imperial Refuge Wilderness.
  1. Plan Ahead and Prepare
  2. Travel and Camp on Durable Surfaces
  3. Dispose of Waste Properly
  4. Leave What You Find
  5. Minimize Campfire Impacts
  6. Respect Wildlife
  7. Be Considerate of Other Visitors
For more information on Leave No Trace, Visit the Leave No Trace, Inc. website.

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