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When David Evans and Associates recently set off to tackle a mapping project of the Gulf Intracoastal Waterway for the National Oceanic and Atmospheric Administration, the firm turned to a unique software system it had installed on an 82-foot hydrographic survey vessel called the S/V Blake.

The firm knew the system could be trusted to handle the task. DEA engineers had created it in-house several years earlier to help keep river pilots and their shiploads safe on the Columbia River in Oregon.

Much of the work that DEA Marine does in U.S. territorial waters,聽along the Northwest coast聽and around the Gulf of Mexico, is for NOAA, according to Jon Dasler,聽DEA’s senior vice president and director聽of the firm’s marine services division.

Its most recent project involved collecting data along the edges of the Gulf that NOAA is using to provide a temporary water route through Chandeleur Sound for the Gulf Intracoastal聽Waterway. The new route will be about聽a聽100-mile聽detour聽for Mississippi River pilots and the thousands of commercial vessels that used the Gulf Intracoastal聽Waterway聽through聽Chandeleur and Breton聽Sound, just inside the Chandeleur Islands, a string of uninhabited barrier islands in the Gulf.

The technology used aboard the S/V Blake provides what Dasler describes as 鈥渇ull-coverage multi-beam聽and side scan聽sonar object detection.鈥� The same system has been used for several years as the basis for an enhanced real-time electronic navigation system to help ensure maritime safety in the Columbia River and Portland Harbor.

Floating a solution

In Oregon, bar pilots meet big ships about 15 miles out at sea and bring them into Astoria. That’s where river pilots pick them up for the eight-hour, 100-mile journey into Portland.

Until a couple of years ago, Columbia River pilots used computer-aided design (CAD) charts, paper copies stuffed in a drawer that had to be constantly pulled out and checked. But the team at DEA Marine designed new software that created electronic versions of the CAD charts that provide much better accuracy with the click of a mouse.

For a long time, Capt. Chuck Patching, one of the 43 members of the Columbia River Pilots, had wanted to incorporate the CAD drawings into the laptops that river pilots use but didn’t know how until Jon Dasler and his team at DEA Marine came to the rescue.

Even in fog or the black of night, Patching said, river pilots can just look at their laptops and know exactly where things are.

鈥淚t can be done much more safely than before and now we have accuracy within inches,鈥� he said.

The DEA Marine computer system, when coupled with GPS coordinates, operates in real time and can show changing ship locations and speeds, as well as the exact location of docks, pilings, shoals and any underwater obstructions, down to the inch, or even less.

鈥淗e (Dasler) took those charts and turned them into (electronic) files that we could read,鈥� Patching said. 鈥淣ow with the click of a button we have the soundings of all the private docks along the river so we can maximize drafts of ships going in and out of the terminals.鈥�

Maximizing draft, the distance between the surface of the water and the lowest point of the vessel, has important economic consequences, Patching said.

鈥淚 can’t stress that enough, that where maybe we were taking a 42-foot draft ship we can now take a 43-foot draft ship,鈥� Patching said. 鈥淭hat doesn’t sound like much, but $250,000 worth of cargo means a lot to the farmer or dock owner or ship owner. That’s a lot of money.鈥�

The DEA Marine’s software can also accurately predict the location of bridge piers 鈥� a critical issue, Patching said.

鈥淲e bring the (U.S) Navy into the (Portland) seawall every year and now we have absolutely accurate predictions of the bridge piers,鈥� he said.

One weakness with the river pilots’ previous system was accuracy of a ship’s position, Patching said. All ocean-going vessels use GPS systems, Patching said, and though GPS is getting better all the time, it is only accurate within feet. The DEA Marine computer system improves on that data drastically and is completely accurate.

鈥淲e get on board and we plug into their system and get their speed and location and all that kind of stuff,鈥� he said. 鈥淚t marries into our software and Jon and his crew were certainly the pioneers of getting that (software system) going.

Exactly how DEA Marine created the software is proprietary, but Patching said he believes the charting system is the best in the country.

Back in the Gulf, DEA Marine crews spent three days gathering data for the alternate route. Charting of the entire Chandeleur Island chain by DEA will continue through December.

鈥�(The technology system is) not just for river pilots but for any interstate commercial traffic that navigates the waterway,鈥� Dasler said. 鈥淲ith these modern methods we’ll have full coverage mapping of the sea floor, looking for obstructions that can be a hazard to navigation.鈥�