Citywide Scrub Seal

The City of Crosby, North Dakota, recently paved major corridors and roadways within the Central Business District. These improvements benefited the community, but approximately 80% of the remaining corridors and side streets needed pavement maintenance.

To address the remaining street needs, the City of Crosby approached Interstate Engineering about potential solutions. The City of Crosby hoped to complete the street repairs by August 4 for the Centennial Celebration.

Initially, thoughts to address the street maintenance included crack seals, chip seal, and micro-surfacing. During the field review, it was noted that many surfaces had transverse, longitudinal, and block cracks. With this information, Interstate Engineering prepared two cost estimates. One included traditional chip seal and sealing of the cracks. The other was for a scrub seal of all the streets.

The scrub seal process melds the crack seal and seal coat process. This innovative method uses a “scrub” broom system that effectively fills pavement cracks and voids, rejuvenates the pavement, and reduces chip loss. A scrub seal is a good option for roadways in relatively good condition with some cracking and without rutting or pavement failures. The expected lifespan of the product is four to eight years.

The preliminary estimate for the scrub seal was lower than the crack seal/chip seal operation. It also included a fog seal of all scrubbed streets, assisting with chip retention. Eliminating the crack seal operation saved time, making it possible for the city to meet the August 4th deadline.

The City of Crosby’s streets were a perfect candidate for a scrub seal because the brooms push the rejuvenating emulsion into cracks, in turn filling the cracks. The streamlined process ultimately saved the City of Crosby money and time and delayed the ongoing maintenance of cracks for the next several years. The 120-block project was completed five days before the contractor’s deadline and $117,000 under the bid price.