Recycled Water for the Thirsty High Desert

The County of Los Angeles (County) includes the Cities of Palmdale and Lancaster which are located in the high desert area known as the Antelope Valley. These two cities combined encompass an area of approximately 200 sq miles and a population of approximately 300,000 residents. Increases in potable water demand and wastewater discharges are serious challenges currently facing this region. The demand for potable water in the region is met largely by imported water from the State Water Project and groundwater pumped from the Antelope Valley Groundwater Basin. However, the water supply from these two sources is becoming less and less reliable. The Regional Water Management Group (RWMG), a collection of 11 local agencies including the Los Angeles County Waterworks District No. 40 (District), is working to meet the water management challenges in the Antelope Valley. In its Integrated Regional Water Management Plan (IRWMP), the RWMG has identified the construction of a recycled water backbone as a critical step to increase water supply and manage wastewater effluent in the Antelope Valley. The North Los Angeles/Kern County Recycled Water Project, Phase 2 (Project) consists of approximately 1,400 ft (0.25 mi) of 30-inch, 42,000 ft (8 mi) of 24-inch, and 5,000 ft (1 mi) of 16-inch diameter steel pipeline, and a 300 horsepower pump station (expandable to 1,000 horsepower) located at the Palmdale Water Reclamation Plant pumping to a new welded steel reservoir at the opposite end of the system. This paper presents an overview of the water history for the Palmdale/Lancaster high-desert area with focus on the community needs and planning decisions that led to the Project. Key design decisions for the Project including selection of pumps and drives to handle demand uncertainties, energy cost analysis, selection of pipeline materials and joint types, geotechnical and corrosion issues, railroad crossings, and an open cut crossing of the Amargosa Creek Channel will also be discussed.