Los Angeles Department of Water and Power: Los Angeles Aqueduct Filtration Plant Modernization – Oxygen Plant Replacement

LADWP is the largest municipally owned and operated retail water utility in the country. It services a population of about four million residents and an area of 464 square miles with an annual water demand of approximately 166 billion gallons. The mission of LADWP’s Water System is to deliver a dependable supply of safe, quality water to its customers in an efficient and publicly responsible manner. Water quality and reliability is a top priority.  Every day, hundreds of LADWP employees work diligently to ensure that customers receive high-quality drinking water. LADWP achieves this by protecting its water sources, using state-of-the-art water treatment processes, prudently maintaining and operating its facilities, and providing vigilant security and monitoring.

The LAAFP treats all of the water delivered from the Los Angeles Aqueduct and the California Aqueduct. Water flows into the plant by gravity and undergoes several treatment processes that disinfect and remove impurities from the water.  The entering water is screened to remove debris, fluoride is added to promote dental health, followed by ozonation to improve the water’s taste and appearance.   Next, flocculation chemicals are added to enhance the removal of particulates in the filtration process.  The treated water is filtered through six-foot-deep filters (crushed coal over gravel).  In 2014, LADWP added ultraviolet light (UV) treatment to the treatment process. UV treatment produces fewer disinfection byproducts and aids in achieving compliance with current and anticipated water quality regulations. After providing treatment to clean the city’s water supply, LADWP utilizes chlorine and chloramine as disinfectants to maintain the quality of the water as it travels through the city’s pipelines. In March 2015, LADWP covered the reservoir located at the facility with approximately 96 million shade balls to improve water quality and reduce chlorination requirements. The shade balls also protect water from sunlight-triggered chemical reactions, wildlife, and the elements.

As aging equipment has been replaced and in the construction of the new UV plant, LADWP has striven to achieve the highest level of energy efficiency in its equipment choices and design decisions.