PORTLAND — Traffic delays are likely for the next few weeks as road crews work to seal cracks on dozens of streets in the city.

The work begins today and is likely to continue through October, city officials said. The plan is for work on residential streets to be done during the day and for the major arterials to be worked on at night.

According to city officials, a rubberized, petroleum-based material will be applied to cracks. Sealing off the cracks prevents debris and water from seeping in, averting damage due to frost and settling and extending the lifespan of the street.