You Don't Drink Treated Sewage? Gross!

By Justin Fox - Bloomberg View 7/29/15

At the end of a tour of Orange County, California's Groundwater Replenishment System -- and they give lots of tours -- a visitor is shown three big sinks with water flowing into them. On the right is the brown brew known as the brine -- the small, salty remnant of water that the facility just can't clean. In the middle sink is slightly discolored water that's been through the first stage of the cleansing process, a passel of microfilters, after flowing in as treated sewage from the Orange County Sanitation District next door. And pouring into the sink on the left is clear water at the end of its journey through the reverse osmosis units, arrays of ultraviolet lights and chemical reactions that extract or destroy salts, bacteria, viruses, endocrine-disrupting pharmaceutical residues and a multitude of other contaminants.

At this point on Monday my tour guide, Mike Wehner, assistant general manager of the Orange County Water District, grabbed a plastic cup and filled it from the left spigot. He took a swig, then handed me a cup. I filled it, and drank from it. The logo on the cup said, "Tastes like water … because it is water!" This was true. Not the tastiest water in the world -- the cleaning process removes most of the minerals that give water character -- but not bad at all.


This clear liquid doesn't go straight to Orange County's taps. About a third of the 100 million gallons produced every day by the $623 million treatment facility, which was built in 2008 and expanded this year, gets pumped into the ground not far away, about five miles from the coast, to keep Pacific Ocean salt water from seeping into the aquifers under the county. The rest is piped inland to the water district's groundwater-recharge basins, not all that far from Disneyland. Later, after local rocks have added some mineral flavor, it will be pumped back out of the ground from wells around the county and delivered to sinks and showers and garden hoses.

Get past all the pumping and repumping and that euphemistic Groundwater Replenishment System name, and it is undeniable that the people of Orange County (or at least the two-thirds of the county served by the Orange County Water District) are drinking treated sewage. Lots of it. The Groundwater Replenishment System, which just added about 30 million gallons a day in capacity, now produces enough to account for 23 percent of the area's water needs in a normal year; the percentage will be even higher this year because of the drought.

This is, let's be clear, pretty danged awesome. If every water system in California were recycling water like this, in fact, the state's urban water users might barely be facing shortages at all during the current drought.

Along with conservation, reclaimed water is the state's great untapped, or at least undertapped, hydraulic resource. Actor William Shatner wants to pipe in water from Seattle, which isn't going to happen. Central Valley farmers want to roll back decades of environmental regulations that restrict their access to water, which is somewhat more realistic -- the U.S. House of Representatives passed a bill to that effect a couple of weeks ago -- but still pretty unlikely. Some urbanites want to pay farmers to stop growing alfalfa, which is already happening to some extent but faces a lot of barriers.

Meanwhile, about 700,000 acre-feet of municipal wastewater is recycled and reused in California each year,mostly for irrigation (of farms but also golf courses, playing fields and the like). Orange County now accounts for 103,000 acre-feet of it. Last year, the Pacific Institute estimated that there's potential for another 1.2 million to 1.8 million acre-feet a year of water reuse statewide on top of that. That higher figure amounts to about 20 percent of normal urban water use in the state. In April, California Governor Jerry Brown ordered the state's urban water users to cut consumption by 25 percent. So …pretty close.

Yet no other water utility in California -- or in the world, as best I can tell -- is recycling water for residential use at anything like the scale of Orange County. Attempts to set up similar systems in Los Angeles and San Diego have so far foundered in the face of public and political discomfort with drinking wastewater. Yet somehow in Orange County, that Southern California land of surf, sand, amusement parks, teen dramasbillionaire fixed-income investors and conservative/libertarian politics, it's all cool.

Why is that? It's largely necessity. With 3.1 million residents, Orange County is the sixth-most populous county in the nation and the third-most populous in the state. But it didn't get really big until the 1970s and 1980s, after California's older coastal cities had already grabbed rights to most of the surface water. And so while municipal providers in the county get some water from the Colorado and Sacramento Rivers via the Metropolitan Water District of Southern California, they're mostly stuck with what the Orange County Water District -- a wholesale supplier of groundwater -- can pump out of the ground.

That groundwater has long been replenished with imported water, storm drainage and the water that flows into the county down the Santa Ana River, Southern California's biggest. In recent decades, much of the river flow during dry weather has come from treated sewage from upstream communities (Riverside, San Bernardino). Storm runoff in a heavily populated area such as Orange County isn't exactly pristine, either.

In the 1950s and 1960s, overpumping started to suck salt water from the Pacific into the county's aquifers. The OCWD addressed this first by injecting imported river water into the ground a few miles inland. Starting in 1971, it began experimenting with using wastewater straight from the sewage treatment plant for this purpose as well. It scaled up that operation later in the decade after the construction of what it called Water Factory 21, a filtering system that was the much smaller precursor to today's Groundwater Replenishment System. The federal government built a desalination facility about the same time that also was used to recharge the county's groundwater, but as energy prices rose that became an expensive boondoggle and was scrapped. It takes a lot less power to clean wastewater, it turns out, than to take the salt out of seawater.

The treated water from Water Factory 21 that was pumped into the ground to form a "hydraulic dike" (Wehner's words) against the sea didn't all stay there; most of it flowed inland and ended up as part of the county water supply. As already mentioned, most of the water that percolates into the ground from the Santa Ana River and from rainstorms starts out of dubious quality as well. So Orange Countians were already drinking formerly dirty water long before the Groundwater Replenishment System started treating water in 2008. The water from the system is actually much cleaner than any of the other water (including imported river water) used to recharge the county's aquifers.

Still, the new facility greatly expanded the use of recycled water in Orange County and the water district treated it as a sensitive endeavor requiring lots of public education. Officials met with 1,200 different groups and individuals in the lead-up; they continue to host about 4,000 people on tours every year. These efforts have worked -- there has been no organized opposition. And why should there be? For Orange County, this is now the cleanest, most reliable, most environment-friendly water source available. Eventually it will probably seem offensive not to reuse wastewater in this way -- not just in California but all over the country and the world. What? You don't drink treated sewage? Gross!

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

  1. This gets discharged into the ocean. It would have gone there in any case, just diluted by a lot more water. 
  2. That's $481 to build the initial facility and $142 million to expand it. 
  3. I got that by taking a 670,000-acre-feet-per-year state estimate from 2012 that was cited by the Pacific Institute and adding in Orange County’s recent 31,000-acre-foot expansion. 
  4. Singapore has a water-recycling operation of similar size, but most of the water goes to industrial uses. 
  5. But they don't have a problem with it in Wichita Falls! This New York Times article has information on some of the other water-reuse projects, as well as more detail on Orange County's. 
  6. The main issue is that the high salt content of seawater is especially taxing for the reverse-osmosis filters that are the core of a modern water-cleaning process. But desalination technology is improving, and there is now another project in the works for Orange County.

To contact the author on this story: Justin Fox  at

To contact the editor on this story: James Greiff  at