Water Ways: The Dutch Are "Rainproofing" Their Big Cities

Mar 11, 2020

Climate change is bringing heavier rain and bigger storms — new challenges for old cities.

Amsterdam is only a few feet above sea level and water has always been a part of the culture. There are more than 160 canals wind through the old city.

It’s a port city, similar to New Orleans in many ways, and officials are trying to completely “rainproof” it by retaining all of the water that falls during a storm, even as those storms drop more rain. For New Orleans, similar solutions might be hiding in plain sight.

Daniel Goedbloed is the program manager at Amsterdam Rainproof, a program run by Waternet, the water management agency for the city of Amsterdam. The program costs about $2 million and is funded partially by sewer taxes.

“When it rains, rivers of water flow through through the streets,” says Goedbloed, as he stands on a pervious parking lot the city built on public property. “So storing water here really reduces the stress on the neighborhoods next by close by.”

“Rainproofing” takes three steps: capturing, storing and draining. The idea with green roofs, rain gardens and pervious parking lots is that they capture the water in place, before it needs to be stored or drained, which is the most expensive part of the system, just like in New Orleans.

The program doesn’t mandate water management and retention as much as it encourages it. Using education, outreach and special certifications, it incentivizes businesses and homeowners to reduce runoff and create more water retention. City-funded projects also include water retention.

To see some examples, one need only step out of the offices of Waternet in South Amsterdam and take a stroll. Just down the street, the city has replaced a public parking lot with pervious gravel to retain the water when it falls. At a nearby school, part of the playground is designed to fill up with water when it rains, at a private office building, the roof is green and covered with sedum, which absorbs most of the rain when it falls.

A green roof in Rotterdam in the Netherlands.
Credit Chris Granger / Times-Picayune | The Advocate

None of these projects are that futuristic or surprising. They’re modest, they fit in with their surroundings, and you don’t even really notice them.

Goedbloed says that’s intentional. The city is going to have to adapt and see climate change not just as a bad thing, but as an opportunity.

“We can use it to make the city more attractive, more green, more livable and more healthy,” he said.

To choose where to build these projects, Waternet ran a couple of “stress tests.” They modelled for a heavy rainstorm that would drop about four inches of rain in an hour to find which streets would flood the worst and where the bottlenecks might be. They focused their projects in those areas.

Goedbloed says his biggest tip for New Orleans is, “hold back the water where it falls and keep it on high ground.” Slow the water down before it even makes it to the drainage system.

Canals, though exceedingly simple technology, are on the best ways to do so. Roelof Stuurman is an urban water and soil expert at Deltares, a water research institute in Delft. He has been a consultant on many projects in New Orleans, and is a big proponent of building more canals. “You'll have less flooding when we have many open canals.”

Geese float in a canal in Delft in the Netherlands.
Credit Chris Granger / Times-Picayune | The Advocate

He says one of the challenges of such a proposal is that people in Louisiana are more averse to canals that the Dutch. They are perceived as breeding mosquitos and posing a drowning threat.

Stuurman argues that those threats are overblown. He says not only would canals lesson the pace at which the city is subsiding, or sinking, due to water being pumped out from the ground, “They also help to improve the quality of neighborhoods.”

If the Amsterdam is any evidence of this, it’s true. The Dutch love canals, their cities are built around them, and all of the nicest homes face the water.

New Orleans architect David Waggonner is also a big proponent of creating more open space for water and retaining it, instead of pumping it out.

“The most beautiful part of the Netherlands is along the canals with the good houses and so forth,” he said. “But (in the U.S.) we don't really build on the water.”

Waggonner wrote the Urban Water Plan for New Orleans a decade ago. It’s a lofty plan that lays out a list of solutions very similar to what Amsterdam is doing — rain gardens, bioswales, canals and green spaces. The price tag is $6 billion.

Waggonner argues that it could pay for itself.

“You can create an economy this way," he said, "you can actually live together well and safely.”

He says New Orleans could become a premier city in water management best practices and export that knowledge.

But he says a bigger issue is that New Orleanians don’t trust the government to protect them from floods: “People here are still afraid they're going to flood again.”

Street flooding at the intersection of Cortez and Banks in Mid City on the morning of July 10, 2019.
Credit Travis Lux / New Orleans Public Radio

Americans have no constitutionally-guaranteed protection from flooding like the Dutch do. It creates this cycle where citizens do not want to pay to support a system that doesn’t work, but taxpayers need to invest in the system in order to improve it.

Ghassan Korban is the head of the New Orleans Sewerage and Water Board. He was in the Netherlands for a conference on water management when our team visited in November. He says he would love to pass new taxes and fund the Urban Water Plan.

Korban says of the Dutch, “There's that level of confidence that I'm paying for a service to the government or to agencies and are delivering and protecting me.”

He says that’s the level of confidence he wants to achieve in New Orleans before asking residents to approve a stormwater fee.

It’s something the city has asked residents to approve in the past, and it has been voted down. Now the Sewerage and Water Board has hired a company to do a rate study, indicating officials are considering a new proposal.

Korban says in order for that to be successful, though, the city needs to build public trust. He didn’t say exactly how he planned to do that.

This story was produced in collaboration with the Times Picayune/The New Orleans Advocate. It is part of the Pulitzer Center's nationwide Connected Coastlines reporting initiative. For more information, go to pulitzercenter.org/connected-coastlines.

Support for the Coastal Desk comes from the Greater New Orleans Foundation and the Walton Family Foundation. Stay tuned all this week for the rest of the series.

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