BLM CA Dos Palmas Geophysical Survey

The Dos Palmas Preserve (DPP) in eastern Riverside County, CA is one of the largest oasis complexes in the desert region of California. Portions of the DPP, including Cox Oasis, provide habitat for threatened and endangered bird and fish species such as the endangered desert pupfish. Until 2006, the springs nourishing this oasis complex were at least partially supplied by recharge through the unlined base of the Coachella Canal, which crosses immediately upgradient of the DPP. In 2006 a new, lined Coachella Canal was constructed, drying up the adjacent unlined canal. The MOU concluded that Cox and Andreas Oases, at the western edge of the complex, were unaffected by canal seepage; as a result, ongoing managed recharge from the canal is targeting the core section of the oasis complex. Yet there is growing evidence that managed recharge is not flowing toward either Cox or Andreas. In addition to the desert pupfish maintained at Cox Oasis, the vegetation at Andreas Oasis is used as part of the riparian vegetation mitigation for canal lining, so drying up of Andreas Oasis would set back vegetation mitigation targets.