LADWP Long Valley Environmental Impact Report Update

The Los Angeles Department of Water and Power (LADWP) will be collecting field data in Long Valley, Mono County in support of the Environmental Impact Report (EIR) for the Mono County Lease Renewal Project. The proposed field data collection will include installation of monitoring wells to help in creating a regional groundwater model.  LADWP released a Notice of Preparation (NOP) in August of 2018 requesting public and agency input on the scope and content of the forthcoming draft EIR. The NOP is available for review at LADWP received many comments from interested parties and has extended the environmental analyses supporting the EIR in response to these comments.

To improve LADWP’s understanding of the hydrology and soils of the area, monitoring wells would be installed at 20 different locations on City of Los Angeles-owned lands in Long Valley. The sole purpose of these monitoring wells is data collection to inform a regional groundwater model. LADWP will not propose production wells, and these monitoring wells will not result in any water export to Los Angeles.

The installation schedule will avoid any potential impact to sage-grouse leks, and the monitoring wells will leave the Long Valley viewshed unchanged.  In the unlikely event that artesian conditions are encountered, the monitoring well would be capped consistent with LADWP well practices. In accordance with the California Environmental Quality Act Guidelines Section 15306, the monitoring well installation is classified as Class 6, basic data collection, experimental management, and resource evaluation activities, which do not result in a serious or major disturbance to an environmental resource.

UPDATE (May 10, 2019): The prior notification indicated that the proposed work would occur in May of 2019. However, the installation of monitoring wells has been delayed due to unfavorable field conditions due to water spreading already underway as part of LADWP’s water management activities.  The proposed is now expected to occur at a later date when site conditions improve.