It includes portions of San Bernardino National Forest, Soboba Reservation, Bautista Creek, and areas along the San Jacinto River in the vicinity of San Jacinto, Hemet, and Valle Vista. In addition to the channelized flood plain, it includes areas outside flood control berms and westward along the river into the San Jacinto Valley and foothills of the Badlands. This unit represents the western extent of the kangaroo rats current range. It includes lands within and between the active hydrological channels of Deer, Day, Etiwanda, and San Sevaine creeks. A large alluvial fan, flood plains, and terraces occur throughout the unit.
Soils are primarily sandy or sandy loam and support alluvial fan sage scrub.
North Etiwanda Preserve. A portion of the San Bernardino National Forest lays within the northern boundary. Proposed lands contain a remnant population of the species and upland refugia from catastrophic flooding. Neither dams nor debris basins exist at the mouths of East Etiwanda and San Sevaine creeks, enabling natural fluvial processes to maintain favorable habitat conditions on the upper alluvial fan and in other portions of the critical habitat unit. Reche Canyon still contains occupied habitat for the species, including active waterways, flood plain terraces, and sage scrub.