Reviving Waterways in the Heart of Paris

The past, present and future are converging in the City of Light. Paris is built on the banks of the Seine River, which winds its way through the historic, cultural, and picturesque city. The Seine isn’t just iconic, it used to be a functional river. In 1900, when the French capital previously hosted the Olympic games, the city used the river for seven swimming events, NPR reports.

Now, as Paris prepares to host the Olympics yet again in 2024, the city is spearheading a huge project to clean up the Seine. If all goes well, this project will inspire a historical and cultural revival in the heart of Paris, and spur on copycat river clean-ups worldwide.

The heart of Paris
Paris was built by merchants into a great city on the banks of the Seine, according to TIME. As the Seine rolls lazily from Burgundy to Paris and out to Normandy, where it meets up with the English Channel, the river passes by some of Paris’s most iconic architectural works, including the Eiffel Tower, the Notre Dame Cathedral, and the Louvre. In fact, Emmanuel Grégoire, the deputy mayor of Paris, told TIME, “The Seine is the reason why Paris was born.”

The Seine river oversaw major, stormy events in Paris’s history that clogged up the river, including absorbing the casualties of a 16th century religious war, and in recent times, discarded  TV sets and motorcycles. 

Wastewater and sewage have also contributed to the polluting of the river’s waters, a casualty of the heavy rainfall Paris receives. When the city is inundated by rain, the current system allows untreated sewage to flow into the Seine, to avoid the sewers being swamped and overflowing onto the city streets. 

Consequently, the river’s become polluted to the point that it’s no longer safe to swim in. Whereas in the past, Parisians used the river for recreation and laundry, and to escape from crushing summer heat, Country & Town House shares that that era seems to have ended.

In 1923, according to NPR, Parisian politicians officially banned swimming in the river due to safety concerns, but the Seine was still used recreationally by adventurous locals until the 1960s when its pollution reached critical levels. Samuel Colin-Canivez, the engineer in charge of Paris’s sewage projects told NPR that the contamination of the Seine peaked in the 70s and 80s, with pollution slowly tapering off in the 90s due to cleanup efforts. 

“Everything was basically dead in the ecosystem,” Colin-Canivez said. “It was in a critical state. The river was just a navigation and tourism route. But since cleanup efforts began in the 1990s, we’ve come back to many species of fish and all kinds of vegetation”

Historical cleanup efforts
The cleanup efforts in the 90s were spearheaded by Jacques Chirac, the then-mayor of France. TIME reports that Chirac promised that within three years, the Seine would be swimmable again. Although Chirac didn’t achieve his campaign promise, he did make a dent in the river’s contamination. By 2022, the Seine had 90 percent less untreated sewage than it did 20 years ago. 

Chirac wasn’t the first politician to undertake a river cleanup. The current sewage system was put into place by Georges-Eugène Haussmann, Napoleon’s city planner, some 150 years ago to keep the city and Seine clean. Haussmann designed a sewer network to collect rainwater and wastewater runoff. 

That system, Colin-Canivez told TIME, was adequate for that time period, but today is no longer sufficient, and in the last century, only band-aid solutions like adding valves and replacing old pipes with newer ones, have been put into place. 

Tanks and tunnels
Now, in the wake of Paris’s 2024 Olympic bid, the river is getting a modern overhaul, according to Country & Town House. The project involves three pieces. The first is a general clean up effort, where garbage is removed from Paris’s streets, to prevent it from reaching the river. 

The second portion of the plan involves building an underground storage tank that can hold more than 1.5 million cubic feet of water. That way, when it rains, there will be a place for the rainwater to go, without flooding the sewers or leeching sewage into the river.

Lastly, the project intends to build a tunnel from the storage tank to a water treatment plant, where it can be treated and released into the Seine.

Etienne Kleitz, who’s in charge of the project, told NPR how the system will work. “We’ll be able to store 50,000 cubic meters of water here during a storm,” she explained. “And when the storm ends and the level in the sewers goes back down, this water will be pumped back into the sewage system instead of being partially released into the river.”

The tank is the meat and potatoes of the project. It will be the size of 20 Olympic swimming pools and will be located near the Austerlitz train station. It’s due to be finished in the spring, several months before the summer Olympic games commence.

Just in time for the Olympics
The Olympics were a big motivation in getting the $1.5 billion  project off the ground, reported TIME. Anne Hidalgo, Paris’s mayor, promised, back in 2016 when she filed the bid for Paris to host the 2024 Olympics, that the competing athletes would be able to swim in the river again, like they did when Paris hosted the Olympics in the year 1900.

In other words, the Olympic bid became Paris’s excuse for an environmental overhaul, Grégoire told TIME: “From 2015, we decided we were going to take advantage of the Olympic Games to considerably accelerate the vision. It was a really important part of the candidacy.” 

If all goes according to plan, the Seine will be ready to welcome Olympic swimmers participating in the 10K swimming marathon, the triathlon, and a Paralympic event. The opening ceremony will also take place on a flotilla of boats cruising for about four miles down the Seine, past the iconic Parisian architecture built on its banks.

Clean rivers worldwide
Not only will cleaning up the Seine transform Paris, but it has the potential to transform the world. Other urban planners are watching the Paris project very carefully, hoping to create similar infrastructure in their home cities.

Dan Angelescu, of Los Angeles-based water-monitoring tech company Fluidion, told the magazine, “The Seine River is maybe the most romanticized river in history, in literature,” and it’s cleanup, “obviously has a lot of emotional impact on people, and definitely acts as inspiration to others.”

Angelescue adds that Los Angeles (the Olympics 2028 host city) has sent government officials to study Paris’s proposal and progress. He said, “I think everybody is watching the Seine cleanup.”

Other cities, like Zurich, Munich, and Copenhagen, have undertaken river cleanup projects with the aim of making their waterways swimmable again. So, if Paris succeeds, it will certainly be an inspiration and model for urban and environmental renewal across the US and Europe.