Julie Brown’s thoughts from last week’s NEWiRE event held at the Isabella Stewart Gardner Museum:
Last Thursday I had the privilege of attending a NEWIRE-sponsored talk on the civil engineering behind the addition to the Isabella Stewart Gardner Museum. Judy Nitsch of Nitsch Engineering spoke in the sitting room of the Palace, once the living quarters of Mrs. Jack (Isabella Stewart Gardener) and as you can imagine, this was a treat.
Judy’s presentation shows that on some of the biggest, grandest projects in the world of architecture, sometimes it’s the things you don’t see that make all the difference, whether they be hidden in plain sight, or buried beneath the ground. [Below are some of the points that make the civil engineering of this new addition so amazing.]
First a little background about the project itself:
Renzo Piano stated in his interview for the project that any addition to the existing museum had to be “the respectful nephew to the grand great aunt.” His vision of the addition is four floating pavilions in honor of the four cornerstones of the original museum: artist in residence, scholarly programs, horticulture/landscape mission and music education.
Section through the New Performance Hall and Special Exhibition Gallery.
© RENZO PIANO BUILDING WORKSHOP, 2010.
Amy Prange, project engineer at Nitsch was responsible for the work on site. Here are examples of civil engineering visitors won’t see:
All of the manhole covers are buried under 12” of soil and trays of grass because the team didn’t want to take away from the aesthetic of the landscape design. The museum lies in the groundwater conservation overlay district, which was developed to protect the existing woodpile foundations in the City from lowered groundwater levels. This ensures that construction projects do not lower the groundwater on their site or adjacent sites, and that they put storm water back into the ground to ensure groundwater stays at a safe level.
Work in a groundwater conservation overlay district requires a volume calculation to determine how much water has to be put back into the ground at the site. In order to do this 1” of precipitation is multiplied by any new impervious areas on the site (pavement, roof) or substantially rehabilitated areas and that product is the volume of water that must be put back into the ground.
The only thing on the site that isn’t buried are the existing palace roof drains which were updated. These downspouts take roof water into the ground, filter and treat it. This dual piping system puts clean runoff into a rainwater harvesting tank while the excess water goes into a recharge system.
Since the palace was not significantly rehabilitated it did not trigger the groundwater overlay district requirement, so water can be captured and reused. Consequently, a portion of the roof runoff is brought into a 2,000 gallon rainwater harvesting tank, then treated and used to water the plants in the greenhouse.
Pervious concrete was used in the parking areas of the new site for better drainage, allowing water to seep through the pavement voids into the soils and recharge the groundwater table. Any excess groundwater from the site (that cannot be absorbed) is piped away from the site, but first treated with a stormceptor, a manhole with a centrifuge, spinning out the solids.
This project is anticipating LEED Gold, and Nitsch Engineering was responsible for three of the points that will help ensure this certification.
After the presentation, our group enjoyed a docent-led tour. How I will ever wander the rooms of a museum without the enthusiasm, knowledge and insight of a docent again, I do not know.
Isabella Stuart Gardner was a woman with big bold visions, practiced in drawing and sketching, who travelled throughout the east and the west, fostering deep friendships with artists and scholars. I encourage everyone to go and see the new addition, but spend time with the great grand aunt – she’s worth every minute you invest.