City officials have suggested that lower demand could allow them to build a smaller version of Phase Two than the City Council approved in 2012. They\u2019ve also expressed concerns that costs for that phase could saddle residents with water bills they can\u2019t afford.<\/p>\n
A consultant hired to handle the re-evaluation recently expanded its analysis to include determining whether the new state method could allow Phase Two to produce purified water from sewage more cheaply and efficiently.<\/p>\n
San Diego is the first water agency in California to explore using the new method and engage state officials on how it could be tailored to overcome any local challenges.<\/p>\n
\u201cWe are at the forefront in the state on this,\u201d said Ally Berenter, deputy director of external affairs for the city\u2019s Public Utilities Department. \u201cWe\u2019re very proud to be that kind of leader.\u201d<\/p>\n
But the new method \u2014 called direct potable reuse, or DPR \u2014 comes with its own set of challenges, city officials say.<\/p>\n
![\"A](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/10\/SUT-L-pure-water-001.jpg\")
A water testing lab at the North City Pure Water Facility operations and maintenance building is seen on Oct. 22, 2025, in San Diego. (K.C. Alfred \/ The San Diego Union-Tribune)<\/p>\n
Because water demand varies by season in San Diego, with demand much lower in winter and much higher in summer, the city couldn\u2019t just immediately pump all the purified former sewage into the water system.<\/p>\n
During winter months when water demand is low, the city would have to store the excess in either a reservoir or some kind of storage basin.<\/p>\n
\u201cThe one big reality that DPR ignores is the amount of water we\u2019re delivering changes drastically throughout the year,\u201d said Juan Guerrero, the city\u2019s public utilities director. \u201cIt\u2019s not the same cost as building a pipeline, but you have to accommodate for some new investment in storage.\u201d<\/p>\n
Another potential problem is the \u201cick\u201d factor. Pure Water Phase One was ridiculed by opponents as \u201ctoilet-to-tap,\u201d an effort to highlight that people would be drinking water previously flushed down a toilet before being purified.<\/p>\n
The purification method the city is using for Phase One \u2014 called indirect potable reuse \u2014 softened that image somewhat by requiring the purified water to sit in a reservoir for months. But DPR would pump it directly into the water system, without any interim storage period during which it interacts with nature.<\/p>\n
Guerrero and Berenter said it\u2019s hard to predict whether the city would face a repeat of the toilet-to-tap opposition campaign. But they said the city will be ready if that happens.<\/p>\n
Berenter said people have become more familiar with the concept of purifying sewage \u2014 and much more trusting of the science behind it \u2014 since San Diego first floated the idea two decades ago.<\/p>\n
\u201cI think we\u2019ve come a long way in terms of acceptance,\u201d she said.<\/p>\n
To soften opposition back then, the city gave hundreds of tours of a \u201cdemonstration\u201d purification plant built on the western Miramar site where the real purification plant was eventually built.<\/p>\n
\u201cWe learned from the toilet-to-tap incident that these demo facilities are amazingly helpful,\u201d said Guerrero, contending that such facilities help soften opposition. \u201cWe might have to ramp it up.\u201d<\/p>\n
Berenter said another concern with direct potable reuse is that it requires\u00a0more rigorous sewage treatment standards that come with higher costs, which could eat into any savings.<\/p>\n
Guerrero also noted that state officials are still working out some details that could affect San Diego.<\/p>\n
\u201cThere are some kinks that need to be worked through,\u201d he said.<\/p>\n
But he said direct reuse also comes with many advantages \u2014 including a potential impact on Phase One of Pure Water.<\/p>\n
![\"Construction](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/10\/SUT-L-pure-water-007.jpg\")
Construction continues at the North City Pure Water Facility chemical tank farm on Oct. 22, 2025, in San Diego. (K.C. Alfred \/ The San Diego Union-Tribune)<\/p>\n
While that phase is based on the old method, the new direct potable reuse rules could let the city leave purified water in Lake Miramar for much shorter time periods than the 60 days mandated under the old method.<\/p>\n
Freeing up storage capacity could potentially allow the city to produce more than the 30 million gallons per day that the Phase One purification plant in western Miramar is slated to produce.<\/p>\n
\u201cIf we produce more water in Phase One, maybe we can invest less in Phase Two,\u201d Guerrero said. \u201cThey all play together.\u201d<\/p>\n
And that\u2019s a key question the consultant analyzing Phase Two must answer \u2014 how much purified water it must produce.<\/p>\n
The 2012 plan called for 30 million gallons per day from Phase One and 53 million gallons per day from Phase Two, for a total of 83 million gallons per day when the entire project is complete in 2035.<\/p>\n
Guerrero said the city might be able to reduce that 83 million to a lower number because of reduced local demand for water and because the Point Loma Wastewater Treatment Plant isn\u2019t at capacity.<\/p>\n
The Point Loma plant is key, because the antiquated technology it uses was what spurred San Diego to conceive of Pure Water in the first place.<\/p>\n
The plant doesn\u2019t comply with the federal Clean Water Act because it can only manage enhanced primary treatment \u2014 not the secondary treatment required.<\/p>\n
When a coalition of environmental groups threatened to sue the city over this problem two decades ago, city officials agreed to build Pure Water and solve two problems at once.<\/p>\n
![\"A](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/10\/SUT-L-pure-water-0915-21.jpg\")
A reverse osmosis system at the Pure Water facility on Friday, Sept. 13, 2024, in San Diego. (Ana Ramirez \/ The San Diego Union-Tribune)<\/p>\n![\"The](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/10\/SUT-L-County-Water-Hike115.jpg\")
The San Vicente Reservoir on Thursday, June 26, 2025, in Lakeside. (Michael Ho \/ The San Diego Union-Tribune)<\/p>\n