GPS to track county plows

A year from now, Spokane County residents may go online when snow falls to find out which roads have been plowed.

Some road graders and plow trucks are being equipped this winter with global positioning system devices that show where road crews are and what they’re doing.

Officials plan to place some of the information online in the winter of 2011-’12, although probably not in real time. They don’t want people approaching plow operators with demands for service.

County Commissioner Mark Richard is eager to reduce complaints by showing snowplowing progress on the Web.

Using cellular telephone connections, the GPS units transmit the location of trucks and graders and whether they are plowing snow or spraying liquid de-icer.

A vehicle appears on supervisors’ computer screens as a blip marking a line along a road. The color of the line changes according to whether plow blades are down or nozzles are open.

De-icing trucks also have sensors for ambient and road-surface temperatures. Mounted on side mirrors, the sensors use infrared technology to detect surface temperature.

County Engineer Bob Brueggeman said the temperature readings will help equipment operators decide whether to apply magnesium chloride de-icer.

He said the experiment began last December with the installation of five GPS units.

“We see this as a possible management tool,” he said. “We can go back and see whether we have a hiccup in our system or if it is a perception problem” when constituents complain that plow crews missed their roads.

Brueggeman said the equipment had been installed only about a week when a sheriff’s deputy requested information for a major collision investigation.

Since April, equipment operators’ concerns about disciplinary use of the system have been answered by piping all the data to their union hall, according to Brueggeman.

“We provided the same access that we have so they can see what we see,” Brueggeman said.

He expects all the trucks and graders in one of four road maintenance districts to be outfitted by the middle of next month.

The GPS units cost $729 apiece, down from $769 when the county began buying them.

Data transmission service for each unit costs up to $40 a month – depending on the amount of use. Brueggeman said the service has been averaging $12 a month, but the cost will rise during a snowstorm.

Each GPS transmitter is capable of sending data from a half-dozen sensors, but the units come with only one sensor.

The four add-on temperature sensors for de-icer trucks cost $510 apiece, putting the equipment cost so far around $17,000.

County street sweepers and vacuum trucks – used to clean out storm runoff dry wells – also have been outfitted with GPS equipment. But the state Department of Ecology paid for that to document efforts to improve water quality by cleaning up oil and other road contaminants.

The snow removal fleet is being equipped at county expense as money is available, Brueggeman said.

This year, the county will be testing the devices on all of its snow removal equipment in District 4, which includes part of Moran Prairie and other unincorporated areas north and south of Spokane Valley, Millwood and Liberty Lake. The district sweeps northeast to the edge of Mount Spokane State Park.

District 4 no longer includes the city of Spokane Valley, which had contracted with the county. The district is being expanded northward to relieve pressure on District 1.

In addition to District 4’s equipment, all four de-icing trucks in the county fleet will have GPS units, for a total of 20 vehicles. Eventually, up to 100 vehicles may be equipped with the devices.

Brueggeman said county officials will study the system this winter to determine the best way to present the information on the Internet.