How Reverse-osmosis Systems Are Helping Breweries Overcome Water Woes

When Green Cheek Beer Company opened in Southern California, the founders needed to navigate various water troubles that eventually helped them dial in recipes and get a better understanding of their beer.

John M. Verive Mar 1, 2018 - 9 min read

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Beyond comprising most of what’s in the beer glass, water’s unique chemistry has tremendous effects on the brewing process and the flavor of the resulting beverage. Historical centers of brewing culture such as Dublin, Munich, and Pilsen grew to prominence largely because of the local water sources that brewers learned to harness even before they learned the chemistry behind the dry stout, the dunkel, and the Pilsner.

Modern brewers know all about residual alkalinity, temporary hardness, and how to craft a water profile to support the beer they imagine, but water chemistry rarely inspires the same passionate discussions that you hear about hops varieties, yeast strains, or even barley cultivars. It’s understandable; water chemistry can be, if you’ll pardon the pun, kind of dry. But one brewer in water-conscious Southern California is putting his years of professional experience with water into play at his new brewery, and Green Cheek Beer Company’s Evan Price is just as happy to geek out about chloride-to-sulfate ratios and gypsum’s place in New England–style IPAs as he is about malt bills or dry-hopping techniques.

“Water chemistry is complicated,” Price says. He struggled with the vagaries of Southern California’s municipal water and fine-tuning water profiles for years. “I’m thankful for those troubles,” he says. “It was a blessing in disguise.”

When Price and his partner, Brian Rauso, launched Green Cheek Beer Company in 2017, they found a shortcut to the years of construction and permitting that building a brewery takes: they took over an existing brewery instead of building one from scratch. Valiant Brewing Company in Orange, California, shuttered in March 2017, and besides the 15-barrel Premier Stainless Systems brewhouse, a cellar full of fermentation vessels, and an onsite tasting room, Green Cheek acquired an Ampac AP2200 reverse-osmosis water-treatment system from the defunct brewery.


Reverse-osmosis (RO) systems purify water relatively efficiently and have applications from the industrial (desalination) to the commercial (food production, brewing) to residential. Price’s mid-career struggles with water chemistry gave him the confidence and skills to control his brewing water, and the RO setup gave him the technical capability to build specific water profiles from the ground up.

Troublesome Water

Price’s road to water-chemistry proficiency began in 2012 when he took the head brewer position at the then-struggling Noble Ale Works brewery in Anaheim, California. Prior to the gig at Noble, Price brewed under his mentor, Victor Novak, at the lauded Orange County, California, brewpub, TAPS Fish House & Brewery. Novak, now the brewmaster at Golden Road Brewing, is a master at reproducing classic styles, and he relied on an RO water-treatment system at TAPS to zero out the often troublesome water supply.

“At TAPS, I never had to learn why you do what you do to water,” Price says. Novak calculated all the water adjustments. “Noble just had a charcoal filter, and I had to learn how to work with a whole new water profile.”

Charcoal filtration removes organic compounds and the chlorine added by municipal water processing, but it doesn’t much affect the mineral content of the water. In drought-stricken Southern California, the municipal water supplies can change month to month as the treatment plants change sources or blending ratios between the mineral-rich groundwater and softer snowmelt and runoff.

“The water in Anaheim is almost like a seasonal ingredient,” Prices says. While struggling with getting consistent results from water additives in the shifting-source water, Price found an invaluable tool for dialing in the water profile for Noble’s brews: a spreadsheet called Bru’n Water.


Developed by veteran homebrewer and water-quality specialist Martin Brungard (who also served as technical editor for the Brewers Publications’ Water: A Comprehensive Guide for Brewers), the Bru’n Water spreadsheet is available for download and is accompanied by a wealth of detailed information about water chemistry from a brewer’s perspective. It was the key that unlocked an understanding of water chemistry for Price, and he says years of experimentation with water at Noble forged a connection between his palate and his brain that wasn’t there before—he’s developed an intuitive sense of how changes to water will alter the flavor profile and mouthfeel of a beer.

Tweaking water-quality variables is “another color on [his] palette,” and while coloring a new beer with more sulfide or chloride will change how a drinker perceives flavor, there’s only so much a brewer can do with a water supply that’s erratic or already loaded with dissolved solids. That’s where the RO setup at Green Cheek comes in.

Reverse Osmosis to the Rescue

The RO water-treatment method removes impurities, minerals, and just about everything else in a water source. Brewers throughout history have adjusted their brewing water to achieve the specific results that they’re after, but it’s tough to take Dublin’s hard, mineral-rich water down to the soft and pure water prized in Pilsen. With an RO setup, a brewery can take whatever water they’ve got, strip it down to almost pure H2O, and build it back up to their exact specifications. The RO water is a blank canvas ready to be colored by the brewer.

The science behind the Ampac AP2200 is straightforward, and pressure is the key to the RO process. Solvent (water) laden with solutes (minerals) flows into pressurized vessel lines with a semipermeable thin-film membrane. The membrane allows water molecules to pass through, but not the dissolved solids. Pressure pushes water through the membrane leaving the impurities behind to be flushed from the system.

The system rejects 99 percent of the solids dissolved in the source water and can recover between 50 percent and 75 percent of the water that flows through it. Additional filtering stages pretreat the source water and provide a final polish before the treated water is pumped into a plastic storage tank.


The RO system provides a steady flow of pure water, but the cost of the utilities to run the system can be high. Besides the space required on the brewery floor and the energy costs of running the system’s pumps, the RO process makes wastewater—almost as much wastewater as treated water. California’s breweries are already sensitive to how much water they use, and RO can add considerable costs and headaches when you’re sending so much more water down the drain.

At Green Cheek, Price combats the flow of wastewater by treating only as much water as needed to brew; he further reduces the volume requirements by blending the pure RO water with some filtered water from the mains. Price is diligent about having the tap water analyzed monthly, and he adjusts the blending ratios as needed. Only about a third of the water used for mash-in gets the RO treatment.

The added effort and costs are a wash in the end, says Price, as the greater control of the raw ingredient means greater consistency in his finished beers. Easily hitting mash pH targets and finding the perfect balance of chloride to sulfate for a refined bitterness is now possible for Price, and more importantly, he’s able to explore the world of styles detached from the constraints of geography and local-water chemistry. Less than a year old, Green Cheek is gaining notoriety for a stream of high-profile collaborations (Firestone Walker, Cellarmaker) and on-trend can releases of hazy New School IPAs, but it’s his continued foray into lager brewing that’s most exciting for Price.

“Playing with water chemistry to make a really impactful IPA is fun, but water chemistry is extra important for brewing lagers,” he says.

A refined, Americanized hoppy Pilsner is a regular feature on the Green Cheek tap list, and Price is also experimenting with that other golden German lager defined by geography: the Dortmunder Export.

“Historically brewers had to learn how to work with the water they had,” Price says. “Today, brewers have the ability to learn how to make their water work for the beers they want to brew.”