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Kino Environmental Restoration Project

Study status:  Complete

Aerial photograph of the KERP siteIn the mid 1990s, the U.S. Army Corps of Engineers, Pima County and the Pima County Flood Control District entered into a cooperative agreement to create the Ed Pastor Kino Environmental Restoration Project (KERP).  This project was the result of the agencies’ desire to redevelop an existing unlined storm water detention basin - Tucson (Ajo) Detention Basin -  into a detention basin that was more environmentally sensitive and aesthetically pleasing to the community.  The multifaceted KERP facility was designed to meet three primary purposes – create native ecosystems, harvest urban storm water and control flooding.

While this project is complete, the District continues to maintain KERP, including the removal of invasive species such as bullfrogs.  The Explorer News recently published an article about the District's bullfrog removal efforts

KERP provides open water plush both riparian and upland plant communities. A riparian habitat is made up of the plants and animals associated with streams and rivers. In the desert these areas are important to many wildlife species. Eighty percent of Arizona's wildlife species utilize or depend upon the resources of riparian areas. The terrain in KERP, visible from a paved walkway around the perimeter, has several different environments and plant communities.

Open Water

In ponds and lakes, open water is the habitat found beyond the shallow water and plants of the shore. Diving ducks feed in open water, seeking out water insects, snails and aquatic plants. Four species of native toads utilize the ponds including the Great Plains toad, the Great Plains Narrow-mouth toad, Couch's Spadefoot toad, and Sonoran Desert toad. Sustainable populations of native aquatic invertebrates provide natural mosquito control. Open water birds to look for are Mallard, Northern Shoveler, Ringnecked Duck and the Belted Kingfisher.


Marsh vegetation communities are found in wetlands, where land meets water at the edge of a pond, lake or river. Wildlife thrives in wetland habitat because of the abundant water and the cover provided by wetland plants like reeds and cattails. Migratory waterbirds rely on wetlands stopover points during their long journeys in the spring and fall. Wetland birds to look for are the American Coot, Red-winged Blackbird, Great Blue Heron and the Black-necked Stilt. 

Cottonwood Willow

Riparian tees like cottonwoods, ash and narrow leaf willow depend on abundant near-surface water available in the river bottoms and banks. Birds to look for in this lush habitat are the Wilson's Warbler, Black Phoebe, Song Sparrow and the White-winged Dove.

Mesquite Bosque

A dense stand or "forest" of mesquite trees is called a bosque. Mesquite trees are especially adapted to our dry climate, sending taproots down as deep as 150 feet to reach water during times of drought. Mesquite bosques provide shade and shelter for wildlife and other plants. Mesquite seeds are rich in protein and are an important food source for many animals. Mesquite bosque birds to look for are the Gila Woodpecker, Ladder-backed Woodpecker, Vermillion Flycatcher and the White-crowned Sparrow.


This habitat contains native grasses and small herbaceous plants. It provides forage, nesting and cover for reptiles, small mammals, birds and insects. Grassland birds to look for include Burrowing Owls plus various finches and sparrows.

Arizona Uplands

Tucson is located in the Arizona Upland Subdivision of the Sonoran Desert where Palo Verde trees, saguaro, cholla and prickly pear cacti are common. Desert birds nest and forage within the protection of these thorny plants, and other animals like javelin, jackrabbits and desert tortoises feed on the cactus pads and fruit. Arizona Upland birds to look for are the Red-tailed Hawk, Gambel's Quail, Curve-billed Thrasher, Cactus Wren and the Greater Roadrunner.


KERP Basins in Action

During major flood events, the KERP project serves it's designed function by detaining flood waters.  Below are some aerial photographs of the filled basins.

Kino Evenronmental Restoration Project (KERP) basins filled with water from the 2014 monsoon rains.

Kino Evenronmental Restoration Project (KERP) basins filled with water from the 2014 monsoon rains.