Active construction of the Orange County Water District’s (OCWD; District) new La Palma Recharge Basin has recently begun
and will continue into the late summer of 2016. The basin is located north of La Palma Avenue, east of the Carbon Creek
Diversion Channel, and south of Miraloma Avenue in the City of Anaheim.
La Palma will join Miller, Kraemer and Miraloma basins that receive and percolate pure Groundwater Replenishment System
(GWRS) product water into the Orange County Groundwater Basin which provides 2/3 of the water needs to residents and businesses
in north and central Orange County. La Palma will be one of only two basins (Miraloma being the second) that is dedicated
to receiving GWRS water. The other basins also capture rainwater, Santa Ana River (SAR) water and untreated imported water.
They are part of a system of more than 20 surface water recharge facilities.
Having the additional recharge capacity for GWRS water will free up other basins to recharge Santa Ana River baseflows and
stormflows along with untreated imported water. This becomes even more critical should the proposed final expansion of
the GWRS treatment plant come online.
What makes the La Palma Recharge Basin unique is that it is the only OCWD basin plumbed exclusively for GWRS water (Although
Miraloma Basin now solely receives GWRS water, it does have the ability to also receive SAR and imported waters). In addition,
the La Palma water level can be lowered so the basin can be operated as two separate entities. The dual basin concept should
help facilitate cleaning one side of the basin while the other side continues to receive flows.
District staff is performing the construction management in-house. This project will involve the excavation and hauling
of more than 220,000 cubic yards of sandy material, construction of a pump station, a 48-inch diameter connection pipe to
the GWRS pipeline, inlet/outlet structures, and perimeter landscaping and fencing.
Recharge basins are extremely important in the management of groundwater supplies for the region. OCWD realizes the need
for constructing additional basins to ensure a reliable water supply.