OCEANSIDE — The city is suiting up for construction of a new facility later this year that will purify recycled water to create a new, local source of drinking water for residents by 2022.
Pure Water Oceanside is a water purification system that aims to reduce the city’s reliance on imported water, improve groundwater resources, increase local water supply and strengthen the city’s resiliency to drought and climate change in an environmentally sound process.
Currently, the city imports 89 percent of its water supply 250 miles away from the Colorado River and 600 miles away from the Sacramento Bay Delta. Ten percent of the city’s water comes from groundwater from the nearby Mission Basin Aquifer and a reverse osmosis process, and the remaining 1 percent is recycled water for irrigation purposes only.
Imported water is subject to rising costs, requires lots of energy to transport and is susceptible to natural disasters like earthquakes, according to the city. Heavily relying on imported water leaves the city vulnerable to climate change and reoccurring drought, and diverting water from the Colorado River and Bay Delta can hurt those ecosystems as well.
Pure Water Oceanside, along with other city programs like its recycled water expansion project, would eventually reduce that imported water rate to 44 percent, with the Pure Water system accounting for 32 percent and the recycled water for irrigation accounting for 24 percent of the city’s water supply.
The project would also help to reach City Council’s 50 percent local water supply by 2030 goal.
Pure Water Oceanside has three steps, the first being its feasibility study which is already finished. The city has spent the last few years completing engineering, permitting, environmental, financial and other studies regarding the project and is currently in the design process.
According to Sarah Davis, environmental specialist for the city’s Solid Waste & Recycling Water Utilities Department, said construction will begin at the end of this year and will finish in 2021. Residents will start receiving the water from this new system in 2022.
Pure Water Oceanside’s system will copy and speed up “nature’s natural recycling process,” creating 3 to 5 million gallons per day of drinking water.
“There’s no new water coming in, just the acceleration of nature’s water cycle,” said Michael Campos, plant manager of the San Luis Rey Water Reclamation Facility.
First, the recycled water will go through a microfiltration process that will remove bacteria and suspended solids from reclaimed water. Next, the water will go through the reverse osmosis process where ultra-fine filters remove salt, viruses, bacteria, pharmaceuticals and chemicals.
The water will then go through an advanced oxidation process using ultraviolet light and chlorine that acts as the “final polishing step” by neutralizing any remaining substances in the water.
According to Campos, the water would be so pure after the advanced oxidation step that minerals need to be added before the water can be injected into the Mission Basin. The water will stay in the aquifer for some time until it is extracted at the city’s Mission Basin Groundwater Purification Facility to be treated again before it is distributed to customers.
The Mission Basin’s water supply has been depleted over time due to years of use.
“Groundwater in San Diego County is rare and we’re lucky to have it,” Davis said. “If the aquifer’s supply goes too low, the ocean water could seep into it.”
Adding water from the Pure Water Oceanside system to the aquifer would prevent ocean water contamination from happening, Davis explained.
Pure Water Oceanside and the recycled water expansion projects would also reduce how much water the city puts back into the ocean. Approximately 8.5 million gallons of water go through the treatment facility daily, but only about 3 million gallons are treated while the remaining 5.5 million gallons go into the ocean.
“It’s really a wasted resource when we send it out into the ocean,” Davis said.
Pure Water Oceanside will cut back on how much water goes to waste in the ocean.
“We’re very excited in Oceanside to be doing this, especially when you live in a desert,” Campos said.
The city is so excited, in fact, that a recent event celebrating World Water Day brought more than 500 people to the San Luis Rey Water Reclamation Facility on March 23 for tours and other activities. While there, guests also learned about the Pure Water Oceanside system.