BOSTON -- Gray is the new green at a new senior retirement development being built in Dedham.

NewsCenter 5's David Brown reported Tuesday that the multi-generational community is harnessing the powers of the earth.

"You start by recognizing that every construction project involves some damage to the environment, and our job is to soften the impact as much as possible," said Len Fishman, of Hebrew Senior Life.

As construction sites go, Hebrew Senior Life is one of the largest in the state. Tucked on 162 acres along the Charles River off Route 128 in Dedham, the company is building a 1 million square-foot retirement community that is sprawling, but also sensitive to the environment.

As the buildings go up, contractors are drilling deep below. More than 400 geothermal wells are being drilled. It is the largest field in the Northeast to harness the earth's constant temperature for heating and cooling.

"It's a sophisticated heat pump that's actually transferring energy from the ground through a heat pump into our buildings for heating and cooling. And it reduces our reliance on fossil fuels," said Michael Crowley, vice president of project management.

All of the independent homes, assisted living, recreation center and the new K-8 Rashi School will use the environmentally-friendly way to heat and cool.

From deep below the earth to high above, even some of the rooftops will be green. Every drop of rain that falls will be captured and used for on-site irrigation.

The drought-tolerant native plantings will take root along side 1,800 trees that will be brought in to replace the trees taken out for construction. All of this is a draw for new residents.

"I think that just the fact that there are culverts already planned in collecting the water. Using the water to water the plants -- that's just saving so much, and for the kids, oh my gosh, it's a real life science," said resident Lorraine Greenfield.

"With all of the talk of climate change and the impact on our water systems, how could they not have been taking steps to minimize the impact down the road. I think we are going to be able to say to kids and others we did the right thing," Fishman said.