Seattle’s Snow-Fighting Approach
The purpose of SDOT’s snow and ice response is to maintain mobility on Seattle’s streets and maintain access to the regional transportation system. They commit to achieving bare and wet pavement on specified streets within eight hours after a lull in the storm. Bare pavement means pavement free of most compacted snow and bonded ice (isolated pockets of slush may persist). The plan is based on nationwide best practices and includes anti-icing, deicing, use of abrasives and specified snow clearing routes.

Anti-icing - Anti-icing takes place before the storm, when snow is predicted with 50 percent or greater certainty. An enhanced salt brine solution will be used to impede the bond between ice and the pavement. Of course, if it is raining, SDOT will use granular salt instead.

Deicing - Deicing removes snow and ice that have already accumulated. SDOT will apply an granular salt to designated routes when snow and ice are on the ground. The application rates for granular salt range from 150 to 300 pounds per lane-mile.

Sand - Using abrasives like sand is important for areas where additional traction is necessary: hills, curves and stopping zones. SDOT is using less sand than previously. This practice eases clean-up and disposal of left-over sand and reduces impacts on drainage systems.

The snow map shows the streets and their service levels. For a copy please contact SDOT at (206) 684-ROAD (684-7623). The Downtown streets are shown in an inset on the map. A copy is linked in this story as well.

Routes were selected using criteria that include the busiest streets that connect our neighborhoods with downtown or within the greater Puget Sound region; streets used by the transit agencies even in harsh weather; streets used most frequently by public safety agencies; and streets deemed important to public institutions such as schools, universities and hospitals, and also Seattle’s major employers.

SDOT has established a treatment service level for each snow route in the city. This is not a priority system – Service Level 1 and 2 will be treated at the same time.

Service Level 1 – bare and wet from curb to curb
Service Level 2 – bare and wet in one lane in each direction
Service Level 3 – deicing treatment on curves, hills and stopping zones.
SDOT has special emphasis patrols to address emergencies and trouble spots.

SDOT will deploy pedestrian safety crews to clear specified curb landings and stairways. These areas were selected using Pedestrian Master Plan criteria.

Facilities and Fleet Improvements

36 trucks and other pieces of equipment have been GPS-enabled with automated systems that report in real time the truck's location and critical snow-fighting data such as application of material and plow blade position. These data are displayed in the Charles Street Operations Center in real time and are archived for analysis and accountability.
SDOT has added two small snow plows with spreaders to its fleet this year. Trucks have been modified so that the granular materials will be properly pre-wetted with the salt brine.
A new work management system will be used to keep track of operational orders given, and the accomplishments achieved against those orders.
The Charles Street Operations Center has been upgraded. A new situation room is outfitted with work stations for Seattle Police Department and King County Metro representatives, and large screen displays of the real-time data system as well as the SDOT traffic cameras. Similar large-screen displays are available to the SDOT dispatchers.
SDOT is constructing covered storage areas at Haller Lake, West Seattle and Charles Street locations for salt. New storage tanks are also being installed for salt brine at each of these locations.

Structure and Training

Preparation for the snow & ice season begins in summer.
Snow and ice equipment is inspected and tested in the late summer, early fall.

In daily operations, SDOT Street Maintenance is configured into two operating sections—Maintenance Operations and Street Repair—and crews are dispatched from three separate locations. In the face of a forecast of probable severe winter weather, Street Maintenance will shift to central control located at the Charles Street Operations Center. This approach is consistent with best practices for emergency management.
When severe weather is predicted, staff will re-orient to our snow event organization, with clear lines of authority and responsibilities.
SDOT has developed a rigorous training schedule to familiarize staff with the new technology and techniques involved in the snow plan.

Communication

SDOT employs a variety of tools and techniques to keep the people of Seattle up to date in the event of severe winter weather.

• Winter Weather Brochure – Seatle DOT publishes a winter weather brochure each year. These come home with kids in public elementary schools, will be available at community centers and libraries.

• Snow Map – This map is your most important tool for knowing what to expect during winter weather. It shows all of SDOT’s snow routes, which match up with Metro’s routes. If nothing else this winter, know the snow map!

• Twitter – SDOT uses this social-networking site to send quick messages to your computer or cellphone about traffic status all year round. During a snow event, you can expect frequent updates on the status of Seattle’s streets. Sign up at www.twitter.com/seattledot

• SDOT Blog – SDOT’s blog is where they spread the word about the work SDOT is doing – new sidewalks, signals, and larger projects. During the winter, you can expect a daily roundup of snow-fighting activities, street closures and other winter weather information. Visit SDOT’s Blog at http://sdotblog.seattle.gov .

• Website – During a snow event, when you visit SDOT’s main web page - - www.seattle.gov/transportation -- you will notice a change from everyday operations. When there is snow on the ground, SDOT’s main webpage will turn into an up-to-the-minute snow removal operational update, including which routes have been treated, what the conditions are, key road closures and links to traffic cameras so you can see for yourself.

Evaluation

During a storm, SDOT will measure and report on our website the status of our snow routes. They collect data about where snow-fighting equipment has been and what sort of treatment was deployed. These data are used to develop information about how successful SDOT is at meeting service-level goals within eight hours of a lull in the storm.

Post Storm Clean-up

The streets on the snow & ice routes are mechanically swept after each storm.
Using less sand reduces the need for clean up, the cost of disposal and the impact on the drainage system.
SDOT performs street sweeping as soon as possible after the end of a storm event to try to minimize the amount of sand entering the drainage system.