Seattle is not using salt to clear the roads because it doesn't want the salt flowing into waterways. As well, the city's snow plows have rubber-edge blades that can clear snow, but can't get the ice off the road. Seattle's DOT cheif says the city is trying to "create a hard-packed surface" of snow. It will then lay sand down over the hardpack in order to offer enough traction to cars, and employ a soy-based de-icer only good for temps below 32 degrees.
The hitch: only 4-wheel-drive and front-wheel-drive cars with chains have any traction. That means that even the police can't drive on many roads. If the police make a call to a location on a hill, they park at the bottom and walk up the hill. As well, the police are having to respond to literally hundreds of collisions and disabled vehicles.
The state DOT has taken a much different tack: it is using sand, salt, metal-edged plows, and chemical de-icer in its battle with the elements. Seattle is now experimenting with a "silver bullet" concoction that is saltwater from a cheese factory, calcium chloride, and de-sugared molasses.
[Source: Seattle Times]