Over three years, crews will initiate nighttime and weekend lane closures to repave stretches of the northbound freeway in Seattle and the South End. Here’s a breakdown of average traffic volumes to be affected.

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There’s no doubt about it: The upcoming overnight and weekend lane closures on northbound Interstate 5 for the massive resurfacing project that began last week will impact tens of thousands of drivers.

But for traffic nerds, that vague accounting means nothing.

For a more exact total of just how many drivers could face delays or route changes as a result of the construction work — which is slated to span three years — we gathered a breakdown of the roadway’s average traffic volume, according to numbers from the Washington State Department of Transportation (WSDOT).

Traffic Lab is a Seattle Times project that digs into the region’s thorny transportation issues, spotlights promising approaches to easing gridlock, and helps readers find the best ways to get around. It is funded with the help of community sponsors Alaska Airlines, CenturyLink, Kemper Development Co., Sabey Corp., Seattle Children’s hospital and Ste. Michelle Wine Estates. Seattle Times editors and reporters operate independently of our funders and maintain editorial control over Traffic Lab content.

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First, here’s a quick recap of the project:

Crews last week began work on the stretch between South 260th Street in Kent and the Duwamish River in Tukwila. And later this year, they’ll target the northbound lanes between Seattle’s Martin Luther King Jr. Way/state Highway 900 in Rainier Beach and Northeast Ravenna Boulevard in Ravenna.

Most of the construction work will occur at night, although crews will close lanes on weekends during the next two to three summers, according to WSDOT. Officials have yet to schedule the closures.

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As part of the first phase, crews will overlay the current road surface of concrete panels with a ribbon of asphalt highway on 4 miles of lanes between South 216th Street in SeaTac and South 178th Street in Tukwila.

According to WSDOT, a daily average of 117,525 vehicles use that stretch on Saturdays and Sundays, while approximately 13,650 pass through overnight on midweek days, between 10 p.m. and 5 a.m.

For a taste of how many vehicles will be impacted by the Seattle closures, a daily average of 111,150 vehicles travel between Mercer Street and Highway 520 on weekends, while approximately 14,800 use that roadway during midweek overnight hours, according to WSDOT.

For live updates on delays and lane reductions, follow @wsdot or @wsdot_traffic on Twitter.