Sedum, a plant commonly used in green roof projects, waiting to be placed outside. Photo: Nick Pandolfo

A small group of alumni and current students from Alfred E. Smith Career and Technical High School in the South Bronx came to school on a Saturday two weeks ago to watch as hundreds of trays of green sedum were loaded onto a low roof of the school.

The event marked the completion of the first city-approved green roof project at a public school in New York City. It is meant to teach students at the vocational school a hands-on approach to building an eco-friendly environment, while also providing cheaper, cleaner environments for Smith.

“It’s really exciting,” said Melany Javier, 17, a 2010 graduate from the architecture program who was valedictorian of her class and member of the Science Club. “This became our baby and it’s finally being born.”

In the blustery wind, for nine hours on Oct. 16, The Green Roof team from Sustainable South Bronx, the local environmental nonprofit that is managing the project, laid 1,400 square feet of sedum, a type of cactus known for absorbing water and reflecting sunlight. Sedum acts as a natural insulator, keeping roofs up to 32 percent cooler in the summer and retaining heat in the winter, and saving up to 30 percent on energy costs, said Smith’s science teacher Nathaniel Wight.

Just hours into the installation, a giddy Wight picked an insect off his shirt he had never seen before, proof that a new eco-system has been created.

The project is not just meant to add a touch of color to the otherwise pebbled roof; it will be the focus of a rich curriculum aimed at helping students apply their skills and knowledge to a sustainable project.

The Smith students’ work can be traced back three years ago with their school’s building trades program. The carpentry classes began building wooden planters for students to grow fruits and vegetables from their native countries.  That project will begin to bear fruit as part of a fresh food initiative in the spring.  Architecture students laid out potential designs of the space, and science students studied the eco-system it would create.

“It’s like a real life engineering problem,” Wight said while directing alumni and current students there to help out. “It’s hard enough to make it something you can use in the classroom, but not so difficult that you need calculus and stuff.”

The City Gardens Club and the New York State Department of Environmental Conservation funded the $40,000 project, and Sustainable South Bronx will stay on in a support role for the next two years as everything develops.

The green roof completed. Photo provided by Nathaniel Wight

The arrival of the sedum was the first step of many, and the green roof is expected to provide an ongoing platform for learning. Smith students will pitch in to plan and build a rain water harvesting system. Art students will work out initial design issues, math students will calculate the boundaries and figure out how much rainwater will need to be captured, and drafting students will use computer programs to create blueprints.

Before next spring, plumbing students will implement the design and build the rain water harvesting system that will sustain the sedum and vegetables being grown. Students will learn how to compost, and then the compost from school cafeteria leftovers will fertilize the garden. The fresh produce from the harvest will be used to prepare healthier school lunches.

The green roof project serves as a bright spot for a school very much in flux. Smith’s building trade programs are in the process of being phased out by the Department of Education, causing uncertainty.  The city said it plans to replace those programs with another building trade program, but the final decision will not be known until next January.

In the meantime, Wight and other teachers will continue to use the roof to educate the students of Smith about ecological sustainability, conservation, and healthy eating.

Two weeks later, the students were back on the roof planting garlic bulbs.

“Green roofs are the wave of the future,” said Colleen Lott, project foreman from Sustainable South Bronx who lives nearby Smith. “And to have a live roof on the top of a school in the South Bronx is exciting.”