River Restoration for Endangered Species
This mile-long section of the Rio Mimbres has been owned by the New Mexico Department of Game & Fish (NMDGF) for several decades. This reach is managed for conservation of the endangered Chihuahua Chub fish (Gila nigrescens) and the listed Chiricahua leopard frog (Lithobates chiricahuensis)–public access is limited and fishing is not allowed. A forest fire in 2006 in the Black Range had left the upper reaches of the Rio Mimbres watershed devastated. Subsequently there have been several very large flow events that originated on burn-scar areas. Sediment deposition and woody debris accumulations from these fire accentuated runoff events had made habitat conditions that were already poor even worse. The river restoration design for this project paid special attention to the specific habitat needs of both endangered species, and preserved the status of the very healthy existing riparian vegetation.
Riverbend’s services to NMDGF included surveying, hydrologic and hydraulic calculations, preliminary and final designs, construction cost estimates, project specifications, and bid documents. In the implementation phase of the project Riverbend provided construction oversight. To mimic natural habitat features where sustainable populations of the Chub are currently found, design relied heavily on woody debris type structures and localized scour pools. Habitat for the frog was created by enhancing natural wetland depressions, and with new off channel ponds that are hydraulically connected to the river.