After a winter season using gravel and sand to improve traction on icy or snowy roads, our streets accrue a lot of debris. As soon as weather permits, we complete a full round of street sweeping across all city streets. Learn about the process below.
The city has two sweepers. The smaller sidewalk sweeper is used first to push material off sidewalks, boulevards, and roadway centerlines into the curbline. The large vacuum sweeper follows behind to sweep and pick up the material gathered into the curbline. The operation also relies on wet roadways to increase efficiencies with material pickup as well as keep the dust down. The City’s water truck is utilized on drier days to assist the two sweepers.
We always sweep downtown and the sidewalks first. Downtown is completed on the night shift, while the residential areas are completed during the day. One of the benefits of sweeping downtown first is that line painting in that area can get started sooner. Plus, if we do happen to get cold temperatures and icy sidewalks after they’ve been swept, we can use salt on them instead of sand where needed.
The City is divided into three zones: The Bench, the Horseshoe, and Southside. We alternate which area gets swept first each year, although the Bench is usually second or third due to its higher elevation and delay in snow melt. While prioritizing busier roads/bike lanes and returning to complete sideroads later has been considered, this leads to merging traffic carrying sand and gravel back onto previously swept routes. Therefore, sweeping one zone at a time has been deemed most efficient.
Street sweeping is not restricted to a particular month or date. It’s entirely weather-dependent. Overnight temperatures need to be -1°C or warmer. Otherwise, if we spray the streets and sidewalks with water and they don’t dry before the temperature falls overnight, it’ll be an ice sheet the next day and we create a different and more dangerous kind of hazard. Plus, the water will freeze in our equipment. It’s just not possible until temperatures warm up, so the timing will depend what kind of winter/spring we're having.
Street cleaning in the spring takes about six weeks, running eight-hour shifts day and night, at a cost of at least $70,000. It is not cost-effective or practical to sweep the streets before temperatures are consistently warmer.
Each street is swept once during the spring cleanup. After this initial cleanup is complete, our sweepers can clean all the streets within about a week, completing this process multiple times throughout the summer to maintain clean streets.