La Mancha Wetland

The La Mancha Wetland project is located on approximately six acres of land adjacent to the Rio Grande near the Town of Mesilla. Half of the area is private land owned by the Southwest Environmental Center. The other half is federal land managed by the International Boundary and Water Commission, U.S. Section.

The primary goal is to restore spawning and nursery habitat for native fish. The target beneficiary fish species for this project are gizzard shad, river carpsucker, blue catfish, longnose gar, and flathead catfish.

Longnose gar are no longer found in the Rio Grande in New Mexico. With projects like La Mancha, we hope to bring them back.

The project consists of a pond that will be excavated on private land. The pond will be dug to a depth below groundwater but shaped to include shallow areas with emergent vegetation. The pond will be connected to the river by a channel that will cross the federally-managed floodway and penetrate the flood control levee via a culvert. The culvert will be gated to allow controlled flows into the pond.

La Mancha Wetland conceptual design.

With the gates open, and when flow levels in the river are at 1200 cubic feet per second (cfs) or greater, water will flow from the river into and out of the pond. At other times of lower flows in the river, the ponds will hold water but be isolated from the river. The project will have the effect of simulating a side channel that holds water year round and is seasonally-connected to the main channel.

The project is approximately two miles upstream from our previous habitat restoration project, the Picacho Wetlands, located within the Mesilla Valley Bosque State Park. The proximity of the two projects increases the likelihood that they collectively will restore sufficient habitat to sustain populations of native fish from year-to-year, using a "habitat bead" approach to river restoration.

As of February, 2016, design work and construction pf the pond have been completed. We are now in the process of installing native plants, groundwater monitoring wells, bat houses, and other finishing touches around the pond. In the meantime, we are beginning the process of applying for a change in point of diversion for our surface water rights, so that we can construct a connecting channel between the pond and the river.

La Mancha Summer 2017 Monitoring-Trail Cameras

Striped Skunk ( Mephitis mephitis)

American Coot (Fulica americana)

Great Blue Heron (Ardea herodias)

Black-tailed jackrabbit (Lepus californicus)

Desert cottontail (Sylvilagus audubonii)

Gambel's Quail (Callipepla gambelii)

You can find more detailed information about the project here.

You can view photos of the project here.

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