KANSAS CITY -- Three years ago, businessman Tom McDonnell and architect Jim Calcara had a vacant lot ready for development as an office building in downtown Kansas City, Mo.. But a collapsing real estate market stalled their plans.

Their answer? Plant a garden. Or several. Corn, lettuce, even a cotton and peanuts, now grow in raised beds near 18th Street and Broadway about a block south of the new performing arts center. It's a $4 million project that serves up fresh food for Harvesters -- Kansas City's food bank community.

Their urban gardens serve as an example of what other cities can do with vast amounts of wasted, vacant lots that create little more than polluted storm runoff, which in Kansas City's case will eventually cost taxpayers billions of dollars.

"We wanted to suggest that maybe the city ought to pay attention to vacant sites and how they're both maintained and perhaps prepared for future development," said McDonnell, chief executive officer for DST Systems, Inc., a financial and computer services company. "The way our site is set up, it's environmentally friendly."

Most cities have at least 15 percent of land going to waste, according to the Brookings Institute.

McDonnell and Calcara, senior partner and founder of 360 Architecture, knew the site now known as 18Broadway had a 25-foot drop from corner to corner -- a potential river of rainfall.

Kansas City already had been figuring out how to meet a court-ordered mandate to spend $2.5 billion on upgrading its aging sewer lines and stormwater management system. McDonnell wanted his land to be a part of the solution.

Construction began three years ago, cutting notches into curbs, so rainwater would run from the streets into swales surrounding the property, then draining into a natural filtering system of deep-rooted plants and into underground cisterns. During a year with 22 inches of rainfall, the site will collect about 2 million gallons of storm water.

"We then use that water, and pump it out to water the garden at night," McDonnell said.

The site also uses solar panels on its gardening sheds and a wind mill to collect energy.

"We figured: if we have this water component, then we went to why can't we generate our own energy to run the pumps to water the gardens>" said Gene Lund of 360 Architecture.

The dream was to make 18Broadway into a sustainable model for urban development in four areas: water, food, energy and shelter.

"What we have right now is kind of the first phase of the total project," Lund said. "We've got the food, water and part of the energy."

The energy also lights the gardens at night, which are open to viewing by the public. The gardens opened last year, and McDonnell said the company has been contacted by other businesses, universities and elementary schools wanting to study the project and its impact on the urban environment.

There's an aesthetic design to the gardens, McDonnell said, that make them look more like landscapes.

"We just didn't drop a bunch of raised beds onto a lot," McDonnell said.

This week, the site also added sculptures that are actually sanctuaries for honey bees.

The challenge was how to manage it.

"At first, we wanted to make it like an urban farm, where people could come in and grow their crops," Lund said. "But the management of that arrangement was going to be a nightmare."

DST, however, had a model. For the past 20 years, its employees have run a community garden at 10th and Jefferson, donating crops to a nearby food pantry. Both DST and 360 employees manage the 18Broadway gardens in teams of eight to 10 people for each bed. During break times in their work day, they can choose to go tend one of the gardens.

The gardens serve as a showcase of various types of sustainable practices. There are gardens in pots that could be used by apartment dwellers and high-yield plots that could serve entire neighborhoods. DST also donated the land for a community garden south at 51st and Main, currently run by volunteers from neighborhood churches.

It's also near where McDonnell lives.

"My wife and I were out walking one Saturday morning, and we saw about 12 people working in the garden at 51st," McDonnell said. "They said they'd already harvested 90 pounds of lettuce. We're talking leave lettuce, and not head lettuce. That's quite a harvest."

It doesn't take a $4 million investment to make a difference, however.

"We made this as a model, so others could take take any part of what we've done and adopt it," Lund said. "You don't have to do the whole thing."

About the same time the 18Broadway project began, Boulevard Brewing started a glass recycling program. McDonnell said Sprint and Hallmark are looking at ways to create projects similar to 18 Broadway with their open land.

"I hope other businesses will see how easy it is," McDonnell said. "Each community should look at what it's particular challenges are and then find a way to solve them. What we have created is a template to show people just what can be done."