Kajima and Biodiversity

The Mitsui Sumitomo Insurance Surugadai Building is a green oasis amidst the high-rise university buildings in the Kanda-Surugadai area of Tokyo.

For over 20 years, Mitsui Sumitomo has graced the local area with its greenery, improving and beautifying the environment. And now the green space is expanding with a new project slated to add more natural scenery to the cityscape on the north side of the building.

Bringing green into the city
A Kajima joint venture built the Mitsui Sumitomo Insurance Surugadai Building in 1984 to serve as the headquarters of Taisho Marine and Fire Insurance. The building stands 25 stories high, and was constructed to achieve two main objectives: “to flourish together with the local community” and “to contribute a value-added space to the local community.” Few buildings were put up back then with any serious attention to environmental concerns, but this one was ahead of its time. At streetside, the building is surrounded by bayberry trees, while a rooftop garden covering 2,614 m2 has been built atop the low-rise section of the building. Kajima was involved in the effort to incorporate maximum greenery into the premises.

The streetside trees and greenery have grown more beautiful with each passing year. After the rooftop garden was renovated in 2003, it won the Minister of the Environment’s Prize in a 2004 contest for rooftop gardens. A number of creative new ideas were implemented after Sumitomo Marine & Fire Insurance and Mitsui Marine & Fire Insurance (the successor to Taisho) merged to create Mitsui Sumitomo Insurance in 2001. The company began letting people tend vegetable gardens on the rooftop free of charge, organized environmental lectures for local residents, and lent its support to the company’s birdwatching club. This “oasis in the city” is highly cherished by people in the area.

Application for designation as special urban renewal district
Mitsui Sumitomo Insurance decided to tear down the annex next door to the Surugadai Building (demolition performed by a Kajima joint venture) and integrate the headquarters operations. The annex design concept matched the beautifully greened main building. The company was able to move decisively on this project because it worked together with the local community to establish a green environmental network, and because it applied for designation as a special urban renewal district (which won the company permission to engage in a project with the needed amount of floor space).

Takafumi Fujino, manager of the insurer’s Global Environment & Community Relations Section, General Affairs Department, has this to say: “Our company is very concerned about biodiversity, so we would like to help maintain an ecosystem in central Tokyo that is friendly to plant and animal life. Toward that end, we believe it is necessary to link up the various green areas that extend in a line from the Imperial Palace over to Kanda Shrine.” This idea of applying for designation as an urban renewal district was a novel approach which garnered the company much praise. The application was approved.

A home for peregrine falcons
Kajima’s “technology for evaluating ecological networks” (see Biodiversity Milestones) has played an important role in the creation of greenery by Mitsui Sumitomo Insurance. According to Satoshi Yamamoto, head of the insurer’s Real Estate Division, “After carrying out an analysis evaluation, we realized that wild birds could flourish in the Surugadai area.” The insurer’s MS Bird Lovers Club actively performs monitoring of birds in the area, and after the new building is completed the project team’s dream will keep growing as they aim to create the third nesting ground for peregrine falcons in Japan.

“In terms of urban biodiversity,” says Mr. Yamamoto, “rather than building semi-natural biotopes, I think it’s actually more progressive to make the best of the nature that we already have around us by using the ecological network concept.”

Demolition of the annex will be completed around July 2009, to be replaced by a new skyscraper and greenery scheduled for completion in the summer of 2012.