Lenain Water Treatment Plant


Anaheim Public Utilities is rehabilitating the Lenain Water Treatment Plant. This plant treats water that is imported from the Colorado River and stored in Anaheim’s Walnut Canyon Reservoir. The treated water from the plant serves residences and businesses throughout Anaheim, providing water supply and meeting maximum day water demands. The plant includes the water treatment facilities, an operation and control center, and a water quality lab. The plant was last upgraded in 1996 and improvements are needed to replace aging infrastructure and improve safety and security. 

This project will replace outdated equipment such as valves, electrical controls, and pumps in the treatment plant as well as valves in Walnut Canyon Reservoir, retrofit facility structures to meet current seismic codes, install a back-up power generator, improve the access road, install surveillance cameras, construct new pipelines, and replace the pavement on the boat ramp. The project will also include construction of a new storage building adjacent to Walnut Canyon Reservoir to house the controls for valves and chemical feed systems.

Project Updates:

Project was completed in October 2020.

Completion of work in project included:

  • Valve replacement and other maintenance work in Walnut Canyon Reservoir.  Currently the reservoir is filled at about 75% capacity.  The reservoir will remain at this level and will be increased as necessary based on water demand and other operating factors.
  • Installation of new influent and effluent pipelines.
  • Construction of the new reservoir outlet structure.
  • Rehabilitation of the boat ramp.
  • Rehabilitation of the flow control facility near the water treatment plant.
  • Rehabilitation work on the treatment facilities is completed. Plant is now back in service.
  • New access road.
  • Installation of new generator.
  • Installation of new bypass pipeline.
  • Rehabilitation work inside the operations building.
  • Installation of educational exhibits throughout the Plant.
  • New landscaping around the Plant.
  • Install informational displays near the reservoir.
If you have questions or comments regarding the Lenain Water Treatment Plant Rehabilitation project, please contact Robert Hoang, Project Manager and Community Liaison, at 714.765.4229 or e-mail rhoang@anaheim.net.

lenain map