Via New York Times (https://www.nytimes.com/2025/05/06/style/coffee-venice-water.html)

Visitors to the Venice Biennale of Architecture will be able to buy espresso made from canal water.

In Venice, beauty and decay have always flowed side by side, borne on waters that are as treacherous as they are alluring. The lagoon makes itself felt as a living presence, through the briny smell that seeps into city squares and alleyways.

An unorthodox project at this year’s Architecture Biennale invites visitors to imbibe Venice in the form of espresso brewed from the lagoon itself — a symbolically rich and scientifically advanced act of transformation and trust.

Conceived by the New York studio Diller Scofidio + Renfro, Canal Café involved two engineering firms, Natural Systems Utilities of the United States and SODAI of Italy, which oversaw the design, testing and monitoring of the water purification system. Aaron Betsky, a critic of art, architecture and design, advised the project.

Canal Café flirts with the language of alchemy — transforming brackish, untrusted water into a warm, fragrant cup of coffee. If it all sounds fantastical, that’s by design.

The project dates from 2008, the year Mr. Betsky directed the Biennale. He invited DS+R to develop a concept that would draw water straight from the canals, purify it in front of the public and brew coffee with it. The project was designed but never carried out because of difficulties in obtaining permits. Now, with advances in filtration and a new push from the 2025 Biennale director, Carlo Ratti, the idea has finally found its moment.

“Regulations and technology have come a far way, and part of the big difference now was that the methodology involved has been one that uses biological filtering rather than chemical filtering, so it’s more organic and natural,” Mr. Betsky said in a phone interview.

The cafe will be installed outside, in the back of the Arsenale, Venice’s former shipyard and armory, which is one of the Biennale’s main sites. Water drawn from the adjacent Arsenal Lagoon will be split into two streams: one filtered biologically through a “microwetland” populated by salt-tolerant plants, and another treated through reverse osmosis and ultraviolet disinfection.

The two streams will reunite to create water that is not only potable but also mineral-balanced. The Michelin-starred chef Davide Oldani will tweak the combination to produce a distinct local flavor. Then he will select the coffee blend and adjust the grind that will deliver the most authentically Venetian taste.

Clear pipes and tanks will reveal every step of the transformation. “It will be very visible: the way the water is traveling from the lagoon into the system and through the espresso machine,” Elizabeth Diller, a co-founder of DS+R, said by phone.

In an email, Mr. Ratti wrote that Canal Café explored “architecture at its most immediate point of interaction — where design meets necessity.”

In a few decades, he said, Venice’s MOSE barrier, the city’s electromechanical flood protection system, will likely be shut almost permanently. After that happens “the city’s biggest challenge won’t just be holding back water — it’ll be figuring out how to keep it clean.”

Clean water, he added, is not only a Venetian concern but also a global one: “We could say that the project is a prototype of the global dilemmas we face in a time of increased climate change when our infrastructures must adapt.”

Mr. Ratti is aware of how provocative the premise of Canal Café might seem. “It’s a challenge we take seriously,” he said. “The idea is to bring a complex environmental issue — water quality — into the simplest acts of our everyday life,” including sipping morning espresso.

Canal Café is meant to engage the body as much as the mind.

“It’s visceral — to drink or not to drink — and will provoke people to confront the issue that is literally right in front of them,” he said. “You’re not just hearing about polluted water and infrastructure failure — you’re drinking a cup of coffee that started as lagoon sludge.” (The espressos will be sold, although the price — 1.20 euros, or $1.36 — is the same as at other coffee bars inside the Biennale.)

Canal Café responds to many of the core concerns Mr. Ratti hopes to address during his edition of the Biennale, for instance, by highlighting how precarious much of the infrastructure is in both our built and natural environments. It is architecture not as a monument, but as a process that involves different fields of knowledge interacting to come up with sustainable solutions.

“We spend so much of our time thinking of a lot of what we see in our natural environment as not worth looking at, as trash, as things that might be offensive to us,” Mr. Betsky said. In his view, one task of architecture is being able to “take what we don’t value, revalue, reimagine it, and show the beauty that is potentially within it.”

The project, Ms. Diller added, is “about combining the sort of pleasure of drinking beautiful espresso while also thinking about the complexity that it takes to actually have potable water.”

When Canal Café opens for business, she said, she’ll be at the front of the line. “I will drink the first cup of espresso, and I will be the guinea pig.”