That's what Parisians hoped a project team would accomplish by executing a seven-year, €1 billion project to redevelop and modernize what was once the site of a beloved open-air market in the French capital. Les Halles became an eyesore in the 1970s after a much-maligned demolition of its signature pavilions to make way for an underground shopping mall and transit center. That project fueled decades of resentment—and skepticism that a makeover could heal the architectural scar.
TOP PHOTO ©FRANCK BADAIRE PHOTOGRAPHE – PBJA ARCHITECTES
Today the site has been reborn: Capped by a sprawling translucent glass canopy, Les Halles also has a new facade, upgraded rapid-transit station, improved mall access and a new public garden. But the transformation required intense stakeholder management, says Emmanuel de Lanversin, the lead project manager, SemPariSeine, Paris, France.
Design of Les Halles in 1863
Eight years of public town hall-style meetings, dueling architectural plans and budget revisions preceded project launch in 2010. Then a massive outreach campaign accompanied the planning and construction phases, with feedback from commuters as well as neighboring residents and businesses—along with a steady stream of demands from the sponsor: the city government.
Les Halles after the 1970s renovation
“We had to put forth trust and transparency all the time.”
—Emmanuel de Lanversin, SemPariSeine, Paris, France
“We had to put forth trust and transparency all the time,” Mr. de Lanversin says. “Every time you move, you're under scrutiny. Every time there was a problem, the media would come.”
To build public confidence from start to finish, the project team created an exhibition and observation deck next to the project site open seven days a week. The exhibit's two staffers showed models of the project and answered visitor questions. The team also provided updates via a project website, email blasts and a biannual magazine, Demain les Halles (Tomorrow les Halles). The team also anticipated sponsor anxiety. For instance, aware that the mayor would be extra picky about the canopy's color, the project team took no chances and built a two-year window into the schedule for color selection. The schedule included building scale models of the canopy and several rounds of reviews.
Although the project was completed one year behind schedule because of multiple surprises, Parisians are grateful for the renovation, Mr. de Lanversin says. “This project enforced the image of a city that's on the move, but our design was respectful of aesthetics and tradition.”
The observation deck during renovations
SHOPPING MALL / ALAMY STOCK PHOTO
Building the €75 million, 7,000-ton canopy was a risk-laden process. The beams alone weighed about 15 tons each. If any of them fell, the damage would have delayed the project for several weeks, Mr. de Lanversin says.
“We couldn't guarantee this would not happen,” he says. “There were no lessons learned to draw from past projects, so we had to compensate—and that always meant more safety people.”
The design and planning teams incorporated double slings and required steel pieces to be cut as small as possible, he says. No piece of steel could be more than 9 tons or 10 meters (32.8 feet) long, says Christophe Maliszewski, director of development, Fayat Metal, Paris, France. Fayat Metal built the frame and glass plates for the canopy.
Work schedules for crews that assembled the heaviest parts of the canopy also were altered to ensure safety for shoppers, commuters, delivery drivers and retail employees. Work couldn't begin until the last employees left, which resulted in a roughly four-hour window each day to mount the canopy's largest pieces.
“It was difficult, precise and very demanding,” Mr. Maliszewski says.
HEMIS / ALAMY STOCK PHOTO
The RER commuter train station and all retail shops had to stay open during demolition and construction. That meant mitigating the impact for the 750,000 commuters and 150,000 shoppers who pass through each day. Closing the shops would have created a combined loss of about €4 billion during the life of the project. Mr. de Lanversin and his team talked with commuters and neighbors before the construction contract was signed to understand their needs and to reduce the chance of project delays.
Demolition work couldn't happen at night, because the vibrations and noise would keep people awake. So the main working hours were 7 to 10 a.m. The project team built temporary corridors and staircases so commuters could safely pass through the middle of the construction site. The team also constantly updated signage to guide commuters and ensure they wouldn't get lost or delayed. “We changed signage pretty much every week, and we had a communications manager inside our company dedicated to that,” Mr. de Lanversin says.
Renderings of a tunnel entrance and the new RER train station, below
PHOTOS COURTESY OF PBJA ARCHITECTES
The mall and RER station—Europe's largest underground train station— encompass six underground levels. Workers on upper levels had to take steps to ensure their tasks didn't interfere with work below them, and vice versa. Coordinating work among so many layers was made more difficult because project managers rarely could draw on standards from projects past. And even when they could, surprises awaited.
For instance, when contractors began demolishing walls to remodel the train station, they discovered the thickness and construction of some walls didn't match architectural plans the project team had reviewed. And the thickest walls had lots of lead and asbestos, which required extra remediation work for which the team had not planned. Mr. de Lanversin's team met with state-owned public transportation operator RATP at least once a week to discuss increasingly difficult hazardous materials removal, among other things.
In the end, the train station remodel took a year longer than slated and was 14 percent over budget, Mr. de Lanversin says. “We constantly had to readjust schedule and planning.”
2010: Project launches; reconfiguration of underground roads begins
2012: Canopy construction begins; demolition of old pavilions complete
2013: Canopy construction completed; renovation of RER train station concourse begins
2014: Renovation of section of garden and reconfiguration of surface roads begins
2015: Reconfiguration of underground roads completed
2016: Reconfiguration of surface roads completed; passenger concourse renovation completed
Emmanuel de Lanversin, CEO, semPariseine
Location: Paris, France
Experience: 25 years
Other notable projects:
1. Boucicaut Eco-Experience: Neighborhood, a residential development project in Paris, France, completed in December 2014. Mr. Lanversin served as CEO of the project management firm that oversaw it.
2. Beaujon, a residential and mixed-use project built over a major telephone facility and data center in the Place de l'Etoile neighborhood in Paris, France. Mr. Lanversin was CEO of the project management firm that oversaw it.
Career lesson learned:
“When a project has a high level of complexity and a lot of actors, you have to set up a dedicated project company to coordinate everybody.”
©FRANCK BADAIRE PHOTOGRAPHE
A new design meant new traffic patterns—for pedestrians and vehicles. After meeting with stakeholders and consultants, the team decided to increase the number of mall entrances from seven to nine. It also improved connections between the mall and the RER station and built more spacious train platforms.
STEPHANE DE SAKUTIN/AFP/GETTY IMAGES
Relying on studies by outside experts, the team decided to repurpose the least essential tunnels. Some of the mall's underground tunnels were converted for other uses, such as trash-sorting centers, delivery zones and even a supermarket.
The outside studies helped ensure that data—rather than politics—would guide effective decision making, Mr. de Lanversin says. Although the mayor and other elected officials were key stakeholders, “it was no big deal to persuade them it was the right decision to close some of the tunnels,” he says. “These highways were built in a time when people thought we should adapt cities to cars.” PM