The city of Oak Harbor is kicking off the summer road construction season this month with “pavement preservation projects” throughout the city.

Public works is completing asphalt overlay and chip seal projects, in addition to the annual overlay work on East Whidbey Avenue between Highway 20 and Northeast Kettle Street, according to the city.

The projects are funded by the city’s transportation benefit district, a quasi-judicial corporation with an independent taxing authority to raise money for road work. Voters passed a measure creating the district and increasing sales tax by two-tenths of 1% in 2018. It raises about $1 million a year.

City Engineer Alex Warner explained the projects in an email he sent to council members. Asphalt overlays, he wrote, consist of a few inches of hot-mix asphalt that is placed on top of an existing road surface. To prepare the roads, it is typical to grind off the top 1 inch of roadway surface to remove rutting and cracks to create a smooth surface for the new asphalt.

Chip seals are a layer of liquid asphalt sprayed on the road and then applied to a gravel layer on top. Sometimes a second coating of liquid asphalt is sprayed on top of the aggregate. Grinding is not included as part of preparing the street for a chip seal.

Overlays provide a longer service life to the road than chip seals do but are more expensive, according to Warner. Overlays cost about five times more than the chip seals per lane-mile.

“This is why we do not overlay every road,” Warner wrote. “We make determinations on whether to overlay or chip seal a road based on their pavement condition index, average daily trips, and other factors. This way we can spread out the transportation benefit district tax revenue from our citizens across the city in the most cost-effective way possible.”

Residents can view the map of project locations on the city website, oakharbor.org, on posters at city hall and on the city’s Facebook page.

The city will continue to provide updates about the projects as they progress.

Residents can stay tuned to city updates and roadway signs to help plan routes around construction projects.