Mapping the depths Maine Lake Charts Inc. maps success in Pittston

Wednesday, June 2, 2004

By MIKE LANGE
Correspondent

PITTSTON -- Imagine spending the better part of 10 days navigating a 28,771-acre lake at 10 mph.

During that period, you've traveled around 800 miles and plotted more than 5,900 points on the lake.

Then, with the information gathered from your global positioning system (GPS) and a laptop computer, you spend most of your free time over the winter creating a comprehensive, detailed map of the massive body of water.

That, in summary, is what Tim Thurston had to do last year in order to create the first comprehensive map of Sebago Lake using modern technology.

"Most of Maine's lake maps on the market are based on information obtained back in the 1940s. In the old days, they simply used a line and lead weight to measure most depths," said Thurston, whose full-time occupation is navigation aids supervisor for the Maine Department of Conservation. "But thanks to new technology, we're able to obtain accurate information that was almost impossible to get 40 or 50 years ago."

Sebago Lake is Thurston's most ambitious project since he founded Maine Lake Charts Inc. in February 2001, a company he and his wife, Delani, operate out of their home in Pittston.

"She takes care of all the packaging and mailing," Thurston said. "We do about 40-50 percent of our business over the Internet and half of those sales are to out-of-staters."

While Moosehead Lake is the largest lake in the northeast at 75,000-plus acres, Sebago Lake, which is believed to have been formed 14,000 years ago by a melted glacier, is Maine's deepest body of water.

So how do you begin to chart a lake? The initial map data is available from the Maine office of the Global Information System (GIS) which shows land contours, roads, streams and rivers leading into the major body of water. Thurston then obtains an aerial map of the shoreline and enhances it on his computer. Then the real work begins as he launches one of his two boats and navigates the lake, plotting points in a specific grid pattern and entering the data into his laptop.

Once the map is finished, it's printed in two formats: an 11-by-17 inch laminated version or a chart that can be folded into a 6-by-11 inch package. The folded model is printed on special waterproof stock where users can write and erase pencil notes without damage.

The charts also include a lot of extras. On the back of the laminated map, there are summaries of Maine laws on the operation of watercraft and disposal of invasive aquatic plants as well as helpful hints on respecting wildlife. The larger, folded maps have a history of the lake, navigation rules and even color photos of the primary fish found in the lake. As an additional service to his mail order customers, Thurston sends out a copy of Maine's fishing and boating laws with each map.

"The Department of Inland Fisheries and Wildlife supply them and it only costs me a few cents more to mail them with the maps," Thurston said.

Like many lakes, the Sebago project had its share of surprises.

"The variance in depth from one point to another is pretty incredible," Thurston said. "The deepest point we measured, 305 feet, is less than a mile away from a 40-foot ridge. Over the years, all lake bottoms shift a bit just due to natural phenomena."

The only part of the lake he was unable to navigate was a tiny section restricted by the Portland Water District, which draws its major supply from Sebago Lake.

So what's in the future for Maine Lake Charts Inc.?

Thurston now has 42 maps available and Sebago Lake is the 16th one that's been completely updated with all new depth data and lake contour lines. Time permitting, Thurston hopes to add China Lake, Thompson Lake in Oxford; Richardson and Mooselookmeguntic lakes, both west of Rangeley; and Long Pond in Belgrade to the comprehensive data list.

"The business is strictly private and out of our pockets. There's no federal or state grant money involved. Basically, I do it in my spare time," Thurston said.

The entire list of maps, prices and even some three-dimensional samples are on www.mainelakecharts.com and Thurston can also be reached at 582-0004 or 485-0330.

To top of page