The “Arctic Blast” of December 2008 was the most significant snow event in 40 years and an event that utilized all available resources – people and equipment. It dropped 19 inches of snow on Portland and was the snowiest December on record (since 1940 when records started being kept). In comparison, the whole winter season of 2008-09 dropped 23.9 inches of snow, the winter of 1968-69 dropped 34 inches, and the winter of 1949-50 dropped 44.5 inches. Portland’s average annual snowfall is 4.5 inches per year.
An arctic air mass caused extremely cold temperatures and strong winds bringing the wind chill factor to the single digits in some areas. Snow accumulated in various amounts throughout the region and State and City crews worked around the clock since Sunday, December 14, applying anti-icing and de-icing chemicals, applying sand and gravel, and plowing streets. Another storm front hit the region Wednesday, December 17, into Thursday bringing minimal snow to the area. A third, very strong winter storm entered the area Sunday, December 21, and lasted into Tuesday. Snow continued to fall Wednesday, December 24.
According to the National Weather Service, this was the worst winter storm to hit the Portland metropolitan region since 1968. This prolonged winter storm event brought to the region extremely cold temperatures, strong winds, freezing rain, sleet, snow showers, and heavy accumulations of snow and ice on streets and highways. Driving conditions were treacherous throughout the first 11 days of the storm, with just a few breaks of warming for a few hours.
The Portland Bureau of Transportation organized for its snow and ice response using the City, regional, and national standard Incident Command System (ICS). It enacted its Snow and Ice Plan to manage operations for response and recovery.
During the two week event (December 14-28), Transportation crews operated two 12-hour shifts per day involving approximately 160 employees and 100 vehicles each shift, applied 30,000 gallons of calcium magnesium acetate as an anti-icing and de-icing road treatment, applied 6,000 gallons of magnesium chloride to sand in trucks to keep it from freezing into solid blocks, and applied 4,600 cubic yards of sand and gravel (enough to fill a football field 26 inches deep).
The incremental cost to provide this 24-hour service over the course of two weeks was estimated at $2.17 million, of which 50% was overtime. Additional costs included fuel, materials, equipment repairs, chains and clean-up. In addition, the City estimated a loss of $337,000 in parking meter revenue primarily in the downtown core.
Crews began sand and gravel cleanup with Night Operations on December 28 and operated five days a week with street sweepers recovering approximately 60% of material laid down. This cleanup effort took about 5 weeks to cover all 1,300 miles of arterials.
Post storm impact to our street system was harsh. Chains on bare pavement, studded tires, sanding, plowing, ice forming under the asphalt, water collecting at intersections and low spots, and the freezing and expanding and thawing of moisture under the pavement are all reasons the system further deteriorated. On average throughout the year, we repair 19 potholes per day. Our pothole repair operations after the Arctic Blast storm averaged 79 repairs per day. The week of January 7-13, 2009 we repaired 555 potholes all around the city.
The Portland Streetcar operated 24 hours per day for 4 days straight from December 20-24 and was able to maintain service throughout the length of the storm.