There are 307 lane miles of primary street routes (like Colorado Blvd) in Thornton. There are 182 secondary route lane miles and an additional 738 lane miles of streets for a total of 1,227 lane miles. Depending on the severity of the storm, the actual miles plowed and sanded are significantly more than the above figure since multiple passes could be needed to keep our major roadways open.
The city divides storms into three classes and responds accordingly.
- Class I - A storm that lasts less than 12 hours; snow accumulations of less than 4 inches.
- Class II - A storm that lasts more than 12 hours; snow accumulations between 4 and 8 inches.
- Class III - A storm that lasts more than 24 hours, snow accumulations greater than 9 inches.
In the event of any snowstorm, the city's first commitment is to clear the primary routes, then secondary routes — and keep them cleared. In the case of a Class III storm (and only in this case) the city will also bring on contract equipment to clear all 738 lane miles of residential streets.
Streets - First Attention
Priorities - The first priority for City plows are the primary routes: the major arterial streets such as Colorado Boulevard, Washington, 104th, 120th, 136th. Next to be plowed are the secondary routes which include local collector streets, school zones, and fire station zones. The last to be plowed are the residential streets. Residential streets are only plowed after major snowstorms such as the blizzard of December 2006.
During a Storm - In a Class I or Class II storm, City crews will plow only selected streets identified as Primary and Secondary routes. Primary and Secondary routes make up 217 miles of Thornton's street system. In a Class I storm, Primary routes are treated within three hours of the snow beginning to accumulate on roadways. Secondary routes will be cleared of snow and ice after the primary routes are completed.
During Class II and Class III storms, snowfall may be so heavy that only Primary routes can be maintained in a passable condition until the storm abates. When Primary routes are clear, then Secondary and Residential routes are plowed. Residential streets are only plowed during Class III storms.
Residential Streets and Plowing Shifts
Residential Streets - After residential streets are plowed, residents will not necessarily see bare pavement. The emphasis for residential streets is to create a single passable lane down the middle that can be navigated by passenger vehicles equipped for winter travel.
Blocked Driveways - During heavy snowfalls, problems arise for residents when mounds of snow left on the sides of streets may block driveways. Although a concerted effort is made to avoid this, it is not always possible. Residential streets are plowed down the center of the street in an effort to avoid covering sidewalks, parked cars, and blocking driveways. The City of Thornton does not remove or haul away snow as part of this program.
Snowplow Deployment and Shifts - When the snow hits, all of our crews and equipment work 12-hour shifts and, the City also has its contractors working to remove the snow.
Sidewalks and Parking Lots
Our Scope of Work - The City removes snow from more than 100 linear miles of sidewalk and trails and 34 acres of parking lots. We also do 2.4 acres of hand shoveling at City buildings, foot bridges and handicap ramps. During the average storm there are approximately 17 employees removing snow — with another 17 available for backup or multiple shifts around the clock. On average there are 15-20 pieces of equipment in use or available for use.
Priorities and Organization - The snow removal for sidewalks and City Facilities is broken down into three routes throughout the city, north; central and south. Each route is plowed simultaneously and depending on the severity of the storm, time of day and time of year the priority for removal may vary. Priorities are City facilities such as City Hall, Recreation Center, Senior Center other city office buildings; city maintained sidewalks within ½ mile of schools; city maintained sidewalks along major arterial streets; sidewalks and trails within park areas.
City Parking Lots - City parking lots are also plowed and ice-treated on a priority basis. It is the intent of the program to have all lots serviced so customers and employees can access City facilities and the City can use these buildings as shelters, if needed.