โ€œHundreds of people lined the riverbanks near the bridge to celebrate. Music and barbecue smells filled the air. The atmosphere was like a carnival.

โ€œVictor Reyes Cervantes, a late middle-aged man who sells tractors for John Deere, recalled the river flowing this big back in the 1950s. He said he hoped that the fish, birds and wildlife would come back along with the river. A young mother keeping watch over her two-year-old son, Leonardo, as he played near the waterโ€™s edge, nodded in his direction and talked of how sad heโ€™ll feel if the river goes away.โ€

So writes author Sandra Postel, recording the March 2014 celebration of a federally managed release of water into the Colorado River Delta in San Luis Rio Colorado, Sonora, south of Yuma. It was the first time in decades that any large amount of water had come into the desiccated delta except during natural floods. She saw joy and hope, tempered by the reality that this pulse of water would last a few weeks at most, because thatโ€™s all the water the feds could release from the over-allocated river.

Hope, but with realism, are the recurring themes of Postelโ€™s newest book, โ€œReplenish: the Virtuous Cycle of Water and Prosperity,โ€ in which the delta restoration forms an early chapter. Postel, founding director of the Global Water Policy Project, tells us where she thinks weโ€™ve gone wrong managing water around the world, and how we can do it right.

Postel will discuss this book, her fourth, Saturday, March 2, at the Tucson Festival of Books on the University of Arizona campus.

โ€œI wrote this book from the place of what I would call realistic optimism, optimism based on the reality of successful projects and solutions,โ€ Postel said.

She decries the proliferation of depleted aquifers, rivers like the Colorado that no longer reach the sea, soil erosion, worsening flood hazards, septic tank pollution, algae blooms, and environmentally destructive water projects.

But her deeper focus is on-the-ground restoration and other, smaller-scale solutions.

For one, she visited the Loess Plateau, along Chinaโ€™s Yellow River, to see what she called one of the planetโ€™s largest watershed restoration efforts ever.

In New Mexico, she visited the Cochiti Pueblo, to study the impacts of ash flows and mudflows into a reservoir there, lying downstream of where the stateโ€™s largest wildfire in history struck in 2011. She later talked to a Nature Conservancy official there about a watershed restoration effort that seeks to raise $21 million a year to rehabilitate burned forests.

She visited a farmer in Californiaโ€™s Central Valley who captures rainfall to replenish a depleted aquifer. And, she went to see a former lawyer who runs a foundation testing โ€œrotational grazingโ€ โ€” moving cattle among pastures to give them time to rest โ€” on seven Texas ranches.

Our past environmental mismanagement, she concludes, โ€œis not a reason to descend into despair ...

โ€œRather, in the vein of the farmers, ranchers, cities, communities, scientists and conservationists profiled in this book, it is time to totally adapt how we live, work and manage our lands and watersheds to prepare for whatโ€™s coming: more extreme floods, droughts and fires, the drying of soils and streams, the shrinking of lakes,โ€ and so on.

The Star talked with Postel by phone last week from her home in Los Lunas, N.M., just south of Albuquerque, for this Q&A:

Q. What made you write this book?

A. We face very big water challenges, as I describe, and itโ€™s easy to descend into despair. But what I show is that a future of depleted rivers, dried-up wetlands, and toxic dead zones is not inevitable.

Here and there, farmers, ranchers, cities, communities and businesses are demonstrating ways of using and managing water that help replenish freshwater ecosystems and repair the broken water cycle, while supporting social and economic prosperity. The challenge is to learn from these experiences and scale them up.

Q. How did our water situation get this way?

A. For a couple centuries weโ€™ve been trading natureโ€™s services for engineering services โ€” for example, building levees to control floods rather than letting natural floodplains do that work. But those engineering solutions are no longer working as well as they once did, in part due to climate change, and their economic costs are rising.

Q. Havenโ€™t these dams and other water projects made it possible to live in arid areas like ours?

A. Weโ€™ve seen in some ways a very successful approach to water management when you look at the prosperity that comes from the dams, all the diversions that bring water from one place to another where itโ€™s needed.

But that kind of command and control style of water management, while flourishing, itโ€™s also broken the water cycle.

Q. What does that mean?

A. Weโ€™ve altered the way water naturally and historically moves between land and sea and the air. Unless we repair that, we are looking at a future of much reduced water security.

Q. Why did you talk so much about soil in the book?

A. One of the things I realized is that Iโ€™ve been working on water for 30 years, but I as a researcher have not paid enough attention to importance of soil, as a reservoir of water. The ability of soil to hold water and store water is critical to food security and to farmersโ€™ resilience against drought.

Q. Your focus on Chinaโ€™s environmental restoration work is interesting. Thereโ€™s the comeback of the Loess Plateau, where scientists worked with villagers to terrace farmland and substitute trees and grass for crops on steep slopes. Thereโ€™s Chinaโ€™s effort to create โ€œsponge cities,โ€ designed to absorb rainwater instead of letting it flood streets and buildings.

Itโ€™s a sharp contrast with the horror stories we read about Chinaโ€™s authoritarian government.

A. I wouldnโ€™t say I was looking there for anything positive or negative. I found their sponge city initiative was an interesting, national scale example, to try to repair the urban water cycle.

Q. How are we doing at upping these environmental fixes to a larger scale?

A. It depends on the particular type of restoration. I find that thereโ€™s a lot more attention now in urban areas to whatโ€™s often called green infrastructure, the idea of turning stormwater from a nuisance into an asset. When you look at Los Angelesโ€™ plan, to reduce its long-distance water imports by half, by using stormwater and recharging groundwater with stormwater, itโ€™s a part of that solution.

Q. What lessons do you have for Arizona?

A. The big picture of concern is of course the long-term drought in the Colorado River system overall. Itโ€™s becoming more and more apparent that itโ€™s already a two-decade drought, and thereโ€™s the need to prepare for an even longer-term drought. Science would suggest with climate change and hotter temperatures, that the Colorado River system is likely to have less water. Itโ€™s time to really pull out the stops and prepare for that.

But Arizona is doing some really good things, groundwater banking, for over 20 years, storing Colorado River water underground, and then Phoenix and Tucson, reducing their outside water use.


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Contact reporter Tony Davis at tdavis@tucson.com or 806-7746.