'Water 4.0,' by David Sedlak
Updated 5:08 pm, Friday, February 21, 2014
The Past, Present, and Future of the World's Most Vital Resource
By David Sedlak
(Yale University Press; 332 pages; $28.50)
With the turn of a tap, clean water flows out. With the flush of a toilet, waste travels to a plant for treatment. It all seems so simple and obvious.
And yet, as UC Berkeley Professor David Sedlak explains in his fact-packed new book, "Water 4.0," such conveniences are really a marvel of engineering, built on centuries of trial and (often) error. More improvements are urgently needed as new challenges like climate change loom. So Sedlak's effort to engage the public on this oft-neglected subject is welcome.
Sedlak's focus is city water systems, and he begins with the ancient Romans. They built an impressive aqueduct network, albeit capped off with lead pipes and fountains, to support Rome's growing population. Subsequent centuries brought efforts to solve the overlapping problems of waste removal and drinking-water quality - challenges made more urgent amid outbreaks of diseases like cholera and typhoid.
But it is the problems and solutions of the past century - and the next - that will seem most relevant to readers. Sedlak explains in detail the technologies to disinfect drinking water, such as sand filters and chlorine, as well as treatment processes for sewage. This is complex science, and "Water 4.0" is not for the faint of heart. Yet flashes of fun creep in: At one point, Sedlak likens a sewage treatment plant to a restaurant, "where the sewage pipes deliver a nourishing stew to perpetually hungry patrons" - i.e., microbes. Elsewhere, he relates how, as a boy at the beach, he used to adorn sand castles with pink tampon applicators - not realizing what they were or that they had come from discharged sewage.
The improvements that have taken place over a lifetime are extraordinary. Here, even after World War II, San Francisco Bay "served as the repository for the region's sewage," he writes. Drivers headed for the Bay Bridge would find a "stink emanating from the mudflats" in Oakland, which was sending its wastes into the shallows at the edge of the bay. San Jose was also using the bay as a sewage receptacle, and "hydrogen sulfide was so prevalent in the neighborhood near San Jose's sewer outlet that the color of freshly painted buildings faded after a few days of exposure to the polluted bay air," Sedlak writes.
Things began to change in the 1950s, after the construction of sewage treatment plants. Further upgrades came after the vital 1972 federal Clean Water Act. They reduced the flow of chemicals into the bay by 88 percent, Sedlak notes, despite the area's continued growth.
Yet much remains to be done. Water systems nationwide are aging even as cities continue to grow. Pipes dating to the 19th century occasionally burst. As for water treatment, utilities now must be on the lookout for endocrine disruptors, toxic metals and even little-known chemicals. Systems that combine wastewater and storm-water drainage remain in widespread use, leading to overflow during storms, even in major metropolises like New York. "The biggest unsolved challenge may now be the pollutants emanating from these combined sewer overflows," Sedlak writes.
Sedlak envisions a next wave of thinking - "Water 4.0," as he calls it - to reshape urban water systems for the future. Some ideas seem a touch fanciful: He envisions reducing cities' wastewater loads via distributed treatment systems, "a network of tiny wastewater treatment plants in the basements of homes and apartment buildings," and using their products for irrigation. The cost would be high, among other challenges.
But he is on track when he cites a fundamental need for investment in systems that the public doesn't think much about except in times of crisis. Saving water, of course, is also key - no state knows that better than California right now.
"If they want to realize the full benefits of conservation, water utilities will have to accept the idea that they are no longer in the business of selling water," he writes. "Rather, they are stewards of a limited resource."