Cleaning Recharge Basins and River Maximizes Percolation

Scrapers, motor graders and bulldozers will be part of the landscape in Anaheim and Orange for the next few months as the heavy grading equipment removes the thin clogging layer of silt at the bottom of each of the region’s more than two dozen recharge basins, owned, operated and managed by the Orange County Water District (OCWD; the District). Recharge basin maintenance is one of the most important factors in percolating water into the Orange County Groundwater Basin from which north and central Orange County pump 77% of their drinking water.

Recharge basins, in all, cover more than 1,000 acres and look like small lakes when filled. They allow surface water diverted from the Santa Ana River, piped advanced purified water from the Groundwater Replenishment System, and imported water to be stored and infiltrated through the ground. This process provides a natural filtering of the surface water before it reaches the aquifer.

In addition, the Santa Ana River, which is the heart of Orange County’s groundwater recharge system, requires year-round maintenance. OCWD owns a 6-mile portion between Imperial Highway and Ball Road in Anaheim. Here, the river is capable of recharging up to 65,200,000 gallons of water every day into the groundwater basin. During the coming months, staff will use bulldozers to remove dry spots along the river bottom, control vegetation growth and channelize flow strategically to maximize recharge and enhance wildlife habitat.

Maintenance is part of an aggressive approach to groundwater recharge that has evolved into an extremely effective system for maximizing the capture and replacement of limited water resources in our area.