This weekend in San Antonio, a new park is opening in one of the poorer neighbourhoods just south of downtown, at a spot where two spring-fed rivers meet. The $13m, three-acre Confluence Park has huge concrete flower petals that will gather rainwater for reuse, and will house educational facilities about sustainable water consumption.

“This park is the place that you will want to visit when it rains,” says Matthew Driffill, recreation superintendent for the San Antonio River Authority.

Known as the “American Venice” for its River Walk urban canal system, San Antonio is now perhaps more efficient and forward-thinking in its water usage than any city in the US, possibly the world.

It wasn’t always this way. In 1982, San Antonio’s water use per person per day was about 200 gallons – considerably more than the national average of 122, and at the expense of its neighbouring cities. San Marcos, New Braunfels and parts of Austin accused San Antonio of over-tapping the 1,250 sq mi Edwards Aquifer they shared, leading to bad blood, particularly during times of drought.

Fast-forward nearly 40 years and the city’s population has grown from 785,000 to 1.5 million, making it the seventh largest city in the US, and the largest to draw its water exclusively from an underground aquifer rather than a nearby lake. Yet over the same period, water use per person has fallen to 140 gallons: a massive 38% drop.

What happened?

San Antonio’s River Walk canals. Photograph: Walter Bibikow/Getty Images/AWL Images RM

‘The people are very upset about this little critter’

“We’ve a history of being contentious about water for a long time, [but] this city now has gained a deep respect for using our natural resources wisely to see that way of thinking as an investment in our future,” says Julián Castro, who was mayor of San Antonio from 2009 until joining the Obama administration in 2014; many have tipped him to run for president in 2020.

“We’ve gotten to a better place now than most American cities, and that is mainly that we’ve come to grips with an issue that cities all over the world are grappling with.”

There are takeaways from San Antonio’s sustainable consumption for cities everywhere. But it learned its lesson the hard way, and from an unlikely teacher: a salamander.

In 1991, resentment towards San Antonio came to a head when the environmental group Sierra Club launched federal court action against the city, arguing that its overuse of the aquifer water was putting a number of endangered species at risk of extinction. One was the Texas blind salamander, an eyeless amphibian that lives only in the water-filled caves of the aquifer. It became symbolic of the court’s decision to force San Antonio to use less water.

The first ruling, in 1993, said that, during droughts, San Antonio would have to reduce the water it pumped from the aquifer by as much as 60%. At the time, many in the city thought it impossible – and subsequent legislative action served only to prolong debate.

The Texas blind salamander. Photograph: Joel Sartore/Getty Images/National Geographic Creative

“The people in San Antonio are very upset that this whole thing is about a little critter,” said Joe Aceves, the chief executive of the San Antonio Water System, of the court-imposed restrictions in 1996. “We’ve got to reach those one million people and show them the benefits of a regulated management plan.”

But over time, changes overseen by the Texas Legislature and collaborative planning by various cities and environmental interests made the shared water policies more workable.

“We had some situations back in those days that just weren’t solvable,” said Weir Labatt, a former San Antonio city council member, at a conference in 2015. “There was no way this issue was going to be solved without some hammer, and that hammer turned out to be the Endangered Species Act … We had a gun to our head.”

In some ways they had no choice. In the 18th century, the Payaya indigenous people settled at the site because of its proximity to underground springs, and it was that access to water that had led to the city’s rapid growth through the centuries. San Antonio knew any future prosperity depended on protecting its only water source for the long term. But to do so it had to change its behaviour – “always a difficult sell”, says Ramiro Cavazos, president of the Hispanic Chamber of Commerce.

“But over time, we all could see the changes were needed and the benefits were very important. It did take some time to improve the water IQ in San Antonio, but that happened.”

A sustainable policy?

The city installed more than 130 miles of pipelines channelling recycled rainwater to golf courses, industrial customers and even into the River Walk’s canals. It devised the aquifer storage program, an engineering marvel, to store rainwater underground, and it replaced 250,000 older toilets and urinals with more water-efficient models.

San Antonio residents were given cash rebates on their bills for using less water, which encouraged the use of native, drought-tolerant plants in landscaping, as well as more judicious lawn watering.

Ken Kramer, a longtime water resource and legislative advisor for the Texas chapter of the Sierra Club, credits the city with implementing better standards following the court case. “Even though it was the litigation that put them into that situation, they did step up to the plate and follow through with an effective and meaningful way in how they provide water to their citizens and the business community,” he says.

Confluence Park’s concrete flower petal roof will gather rain water for reuse. Photograph: Airborne Aerial Photography

The current mayor of San Antonio, Ron Nirenberg, says the lessons learned will stand the city in good stead. “Perhaps we have been forced to see this as hugely important faster than most cities, but the fact right now is that for the first time in human history, more people are living in urban communities than rural ones, and providing safe and clean and cheap water for these people in cities is a global challenge.

“Making sure the world’s populations are supplied with potable and available water is priority number one these days, and I think San Antonio’s water policies and programmes can be a model for cities all over the world.”

But with the city’s population forecast to grow by more than 30% by 2040, more challenges lie ahead. San Antonio is looking to prepare for that growth by piping in water from neighbouring aquifers at multi-billion-dollar expense. But many think the city should be further reducing water use to accommodate growth, not buying more.

“The cost of water to the average homeowner will skyrocket if we don’t have restrictions,” says Amy Hardberger, associate dean of the St Mary’s University School of Law in San Antonio and an expert on water conservation policies. “We need to think of water as a shared community resource.

“If you overwater your lawn, it affects someone who draws on water from the same aquifer 100 miles away. We must always be thinking of how much water is needed and at what cost.”

Mayor Nirenberg says population growth is “not a goal” of the city but an inevitability, and one that poses undeniable challenges for water policy restrictions.

“We feel pretty confident that we can handle that growth with responsible management of water and clean air and good green space like the Confluence Park,” he says. “A good business climate and quality of life and environmental protections go together and we know that. We’re pretty confident that our children and grandchildren in San Antonio decades from now will expect that way of thinking.

“That’s our goal.”

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