Inaccessible New York Earth Day Special: The 5 Boro Green Roof Garden

by Evan Bindelglass, CBSNewYork.com

NEW YORK (CBSNewYork) - In our series, Inaccessible New York, we've been visiting places that are off limits to the public. Well, this one has a twist because you can go there - it's just not that easy to do.

In advance of Earth Day, I took a trip out to Randall's Island, which, if you're wondering, is officially part of Manhattan, and arrived at the NYC Parks Dept. Five Borough Garage and Shops building, which, at first glance, isn't all that interesting.

But if you look closely, it appears there are things growing out of it.

Up on top is the 5 Boro Green Roof Garden, which is the largest multi-system green roof on the planet.

I was given a tour by Artie Rollins, Assistant Commissioner of Citywide Services for the New York City Parks Department.

Right now, they're still getting the roof ready for late spring and summer.

The plant in the middle is breaking through.

Here's how it all started. Six years ago, Liam Kavanagh, the First Deputy Commissioner of the Parks Dept., asked Rollins to look into green roofs. Rollins and his team started researching and got to work.

Rollins said there are now 30 different types of green roof systems on the roof, taking up 30,000 square feet. There is room to expand to one acre, which is their goal for about a year from now.

"The systems vary from the depth, the type of growth medium, the type of plant life, the amount of water it can sequester, and then the other benefits - insulation, heat island effect. So, each system is distinctly different," Rollins said.

(Click on the photo below to read the entire display.)

The heat island effect, also known as the urban island effect, can cause cities to be as much as 10 degrees warmer than surrounding suburbs or countryside, according to the Parks Department.

The effect is due to a mass of hot air that hovers over cities because of the heat absorbed and reflected by roofs and roads, for example. Green roofs help to reduce the temperature and minimize the heat island effect.

Most of the systems are around 20 percent organic, with the rest being an inert material, which is what makes a green roof different from a roof garden, Rollins said. It is lightweight compared to its benefits.

One of the systems is a solar green roof system. Rollins said when the temperature of a solar panel tops 100 degrees, its efficiency drops off. However, being on a green roof keeps the panels cool and, therefore, more efficient.

These panels power a system of roof lights.

There are several benefits to having a green roof, Rollins said. They include saving up to 30 percent on energy costs, lowering maintenance costs, keeping the building cool, and protecting the roof.

You can see this system is right next to a rooftop air conditioning unit.

"On a 90 degree day, if this roof was… black, it would be pulling in 160 degree ambient temperature," Rollins said. "But right now, because it's adjacent to a green roof, on a 90 degree day, it pulls in 90 degree air. So, we're pre-cooling that air."

Another benefit is storm water retention. The green roof retains storm water and keeps it from going into the city's water and drainage systems, which saves money because the Department of Environmental Protection doesn't have to build additional infrastructure to process the water.

The water that ends up on the roof, but not in the planting areas, is collected in these drums and reused on the roof. They're able to hold 6,000 gallons of water.

During the summer, they grow fruits and vegetables in their 4,000-square-foot farm on the roof. The Parks Dept. brings as many as five boxes a day to a soup kitchen in Manhattan.

"When you have a green roof in New York City, what we've found is because of the potential toxicity in the soil, you don't want to have carrots and potatoes that grow in the soil," Rollins said. "So, what we have is tomatoes - five or six different types of tomatoes, five or six different types of peppers. We have cucumbers, zucchini. Also last year we introduced a row of corn that helps screen the farm from the wind. It helped that a lot." He said they also had strawberries and cantaloupe last year.

They don't just grow plants on the ground. They also grow them hydroponically. Here you see plants in full bloom.

This courtyard on the second floor is green, too.

They're even growing green walls. See the black crates on the side of the stairwell exit? They're also going to grow stuff there.

They have worms up there, where, as you can see from the hole in the photograph, birds have been hoping to find them.

They also have a hawk that often stops by the roof. So, they've built a platform for it to land on.

They also do urban beekeeping on the roof, and the bees pollinate the plants.

The green roof isn't a bad place for lunch, either, especially when the weather is nice.

There are also green roofs on many other NYC Parks buildings around the city, including 10 recreation centers. The Parks Dept. has one million square feet of flat roof and would love to be able to turn them all green.

Rollins does tours of the 5 Boro Green Roof Garden for groups ranging from curious schoolchildren to condo boards looking for ways to save money.

The easiest way to get there is by car, as you can't get there by subway. There is also limited bus service.

If you'd like a tour, contact Rollins at 212-360-8905 or Arthur.Rollins@parks.nyc.gov.

Many thanks to Artie Rollins and Vickie Karp at the Parks Dept. If there's an "inaccessible" spot you'd like Evan to check out, share your idea in the comments section below.

You can follow Evan on Twitter @evabin.