You can get there from here

Ayres Associates embarks on a map quest

By Sean Ryan

Madison This elevation map of downtown Madison uses Light Detection and Ranging technology. Map images courtesy of Ayres Associates Inc.

It used to be that a map could stand the test of time.

That was when everyone in a county knew about the latest construction project, and everyone and their brother knew when a piece of land changed hands.

Now, a new map in 2000 is old news in 2005. And American Transmission Co. had a big piece of old news on its hands when it set about routing 500 miles of new power lines in southern and north central Wisconsin.

The company’s maps were based on aerial photographs taken in 2000, and old maps don’t cut it for planners in search of undeveloped land, said Brian McGee, American Transmission’s team leader of geographic information systems. The company couldn’t just pretend everything built in the last five years didn’t exist.

“The photos from 2000 are just that — it’s a snapshot in time,” he said. “We don’t know what’s out there based on the 2000 photos.”

There were solutions, but they weren’t cheap. The company could’ve bought recent satellite photos of the Earth or, as a last resort, bought new maps.

Langlade County This infrared image of Langlade County helps officials identify tree species and determine how healthy they are. Map images courtesy of Ayres Associates Inc.

And it was while American Transmission was considering its options that Kirk Contrucci called with a possible solution.

Contrucci, manager of photogrammetry for Ayres Associates Inc. in Madison, was leading the largest mapping initiative in Wisconsin’s modern history. With 182 public and private contracts, totaling nearly $4 million, his job was to create maps for the 35 counties that make up the northeastern third of the state and cover more than 15 million acres.

He offered American Transmission the chance to buy in and get all of the maps, and McGee said he jumped at the opportunity.

The Ayres project marks a step forward in the way Wisconsin governments buy maps. In the past, local governments independently released contracts every five years to map the land they regulate.

But that changed in 2004 when the East Central Wisconsin Regional Planning Commission was gearing up to buy some maps to replace 2000’s batch, said Andrew Jennings, the commission’s information technology coordinator. Jennings heard three member counties were doing the same thing, and they dreamt up a partnership.

The group discovered the Bay-Lake and North Central Wisconsin regional planning commissions were in the same situation, and things snowballed.

“We put our heads together, and we decided to do a multiregional RPC effort, and the next thing you know, it steamrolled into a larger program,” Jennings said.

Fond du Lac This shot of Fond du Lac gives municipal engineers more information than a traditional map because it shows curbs and driveways, the locations of trees and other planning information. Map images courtesy of Ayres Associates Inc.

The partnership set up a public-bidding process and selection panel that sifted through seven proposals before assigning the task to Ayres.

“We had some concerns about whether or not a contractor could handle such a large area,” said Jeff DuMez, GIS/Land Information Office coordinator for Brown County, one of the 182 clients.

Contrucci’s team met with every client to find out what level of accuracy each wanted, and if they wanted Ayres to add GIS layers showing additional information. Each client was saving roughly 25 percent just from the economics of scale, but the ability to tailor each set of maps allowed smaller clients with tight budgets to participate.

For some, it was the first time they could afford maps.

“The more accurate and the more complete it is, the more expensive it is,” Contrucci said. “Some of them don’t need us to do the GIS, and some of them need us to go through every single step.”

Ayres called in its air support in spring 2005.

A fleet of airplanes — seven during peak operation — spent seven weeks flying over and photographing every mile of the 35 counties. The planes were equipped with Light Detection and Ranging equipment to let Ayres engineers build elevation measurements into the maps.

Oneida County This bird's-eye view of Oneida County is a baseline image that planners can use to create maps. Map images courtesy of Ayres Associates Inc.

LiDAR shoots a beam of light from the belly of the plane and, based on how long it takes to bounce back, measures changes in elevation. But it must be done in spring or fall because there are no leaves on the trees and the undergrowth is short.

By the time summer rolled around, Ayres’ five terabytes of computer memory were humming with countless digital images of Wisconsin and corresponding data measuring the heights of hills and buildings and the depths of valleys and ditches.

Next, Contrucci’s team must turn the photos and data into actual maps. A team of 33 people in the Madison office will spend about a year completing all 182 contracts, and it plans to wrap it up this spring.

The final product represents a mix of photos and line-drawn maps. It’s a picture of the Earth’s surface, but the placement of roads and streams and borders is as perfect as any drawn map.

The maps are decision-making tools that can guide any choice involving the Earth’s surface. The city of Madison can use them to track lines of sight to the state Capitol or to tackle radio communication interference downtown.

The maps will be used to help fire trucks and ambulances find the fastest routes to emergencies, and they’ll help guide snowplows. They track growth and decline of forests and lakes. They can label ground as pervious or impervious so planners can model storm-water flow.

Sometimes they’re just a handy visual aide. Cities must service their fire hydrants every three years, and they can now use a map to set up a three-year plan to complete the cycle more efficiently.

“We’re a very visual species — with everything, we want to see it,” Contrucci said. “You are making a positive contribution to society.

Lambeau Field This image of Lambeau Field in 2005 is not a photograph. Ayres tweaked a picture to remove optical distortion so the image functions as a perfectly accurate map called an orthophoto. Map images courtesy of Ayres Associates Inc.

“You are helping to plan for better communities. You are helping to protect the environment. You are helping to make better response times to emergencies. These are all important social issues.”

The maps will be used for community planning in all 35 counties, Contrucci said. And they will be especially helpful to the city of Platteville, which is preparing for an anticipated building boom.

The state is wrapping up the expansion of Highway 151, a four-lane bypass that will channel highway traffic a few miles south of Platteville’s central area, said Howard Crofoot, Platteville director of public works.

“What we expect is that over the next however many number of years, there will probably be development along the corridor and then infill between the current city development and the corridor,” he said.

The maps will help city planners prepare for more than 1,000 acres of anticipated new development on what is mostly agricultural land without sewer service. Crofoot said the new maps will replace the city’s set, created in 1995, and the improved resolution will allow Platteville to plan its sewers; the maps can help planners gauge what water pressure a building would get from the city’s lines.

“That stuff is basically run by gravity — downhill — and you want to have a pretty good knowledge of where the peaks are and where the valleys are so you can use that,” he said.

Although Ayres hasn’t yet completed the 2005 maps, its clients are already brainstorming a statewide mapping effort for the next round in 2010. Jennings said the consortium is already laying the groundwork, and American Transmission’s McGee said he’d be game.

Wisconsin State Cartographer Ted Koch said it’s what the state should be doing.

“There’s probably 10 states doing that, and, ultimately, that’s where we should be in Wisconsin,” he said. “It’d be a great idea. It’d be better than these consortiums.”

And while Contrucci said there’s no way of knowing what the cartographic technology will be like in 2010, he guessed it would be better than in 2005.

“Everything improves with time,” he said. “How sad would it be if it didn’t?”