MALIBU, CALIFORNIA; A STORY OF WASTEWATER, POLITICS AND SCIENCE

The City of Malibu was tasked with developing a plan to alleviate the water quality impacts to the shallow groundwater, lagoon, and ocean from On-Site Wastewater Treatment Systems (OWTS) by the Los Angeles County Regional Water Quality Control Board (LARWQCB). The City of Malibu does not have a public wastewater system, therefore, residential and commercial facilities use either leach fields or seepage pits to dispose treated wastewater. The type of wastewater treatment varies from basic septic systems, to advanced membranes and ultra violet (UV) systems.

In 2009, the Los Angeles County Regional Water Quality Control Board (LARWQCB) adopted Resolution No. R4-2009-007 entitled Amendment to the Water Quality Control Plan for the Coastal Watersheds of Ventura and Los Angeles Counties to Prohibit On-Site Wastewater Disposal Systems in the Malibu Civic Center Area. This resolution, and the prohibitions it contains, applies to all discharges in the Civic Center Area of Malibu and requires the cessation of all existing OWTS and the development of a centralized wastewater treatment system. In the years leading up to the Resolution, the City began to collect data required to characterize the underlying groundwater basin and develop a groundwater flow model. The City ultimately determined that the effluent generated from the centralized wastewater treatment plant would be treated and used for irrigation and the surplus water would be disposed of using a series of injection wells.