Remember this scene from early June on I-66 in Falls Church? With the SafeTrack surge starting Wednesday, the only known difference is that the Metro crews will be working on the opposite track. (J. Lawler Duggan/For The Washington Post)

[This post has been updated.]

As Metro begins its fifth special maintenance project Wednesday under the SafeTrack program, some commuters on the west side of the Washington region may be experiencing Surge fatigue. This new project covers the same section of tracks between East Falls Church and Ballston that was repaired during the first surge. And according to a new report, that project had the greatest effect on traffic of any launched so far.

During that surge, from June 4 to June 16, congestion and travel delays increased, particularly on eastbound Interstate 66 in the mornings inside the Capital Beltway and along Route 50 and the Dulles Toll Road. Drivers also complained about traffic on the Key Bridge, M Street NW, the Roosevelt Bridge, Constitution Avenue NW and other important commuter routes on the west side of the District.

The new report from the regional Transportation Planning Board staff says, “Traffic during each of the first four surges tended to be worse than the same days in 2015, but Surge 1 saw the greatest impacts.”

Travel times on highways were about 10 percent longer on average during the morning commute than in 2015, and about 15 percent longer during the afternoon commute, the report says. During Surges 2, 3 and 4, the traffic effects were much smaller. Arterial roadways, the major commuter routes, saw an average increase of less than 3 percent.

Surge 1 (blue), during which Metro worked on the tracks between East Falls Church and Ballston in early June, produced the greatest spikes in traffic congestion. (Transportation Planning Board image)

In the traffic data analyzed by the TPB, portions of I-66, Route 267 (the Dulles Toll Road and the Dulles Connector) and the George Washington Memorial Parkway experienced travel-time increases double the typical morning commute — or greater.

It’s possible that a normal summertime decline in traffic congestion will ease the effect of Surge 5, compared with Surge 1.

“In the past, the TPB has consistently found that travel delay drops about 15-20 percent during summer months when schools and Congress are out and more people have greater flexibility in their travel schedules,” the report says.

But don’t let that lull you into a false sense of security about this one. Traffic conditions gradually get better as the summer advances into August. But the weekday traffic maps and cameras show that many drivers still are on the roads at the height of rush hour.

INRIX traffic data shows the decline in average a.m. travel times on I-66 inside the Beltway from June to July in 2014. (INRIX image)

Bob Pishue, senior economist with INRIX, the traffic information service, looked at morning travel data for I-66 inside the Beltway on Tuesdays, Wednesdays and Thursdays for June and July between 2011 and 2015. “There is a noticeable difference in travel times between June and July, with July travel times generally lower than June,” he said. But there is some variation from year to year, he said, and the gap in average travel times narrowed in 2015, with July and June following each other closely.

So I-66 drivers should not count on having an easy time dealing with the latest SafeTrack surge, despite the seasonal shift.

Among drivers’ complaints during Surge 1: Many of the regular carpoolers said they were seeing many more solo drivers illegally using I-66 eastbound inside the Beltway during the HOV-only hours of 6:30 to 9 a.m. I also noticed a surge in traffic just before and just after the HOV time period.

The June-July declines in travel time are consistent, but in some years — like 2015 — the gaps narrow. (INRIX image)

“One of the main observations from Surge 1 was an extended or shifted rush hour,” said Jennifer McCord, a spokeswoman for the Virginia Department of Transportation. One thing that the VDOT traffic monitors can do is extend the rush-hour traffic-signal plans, and McCord said officials will continue to do that for Surge 5.

Because of the SafeTrack projects, the District has extended its rush hour parking restrictions by half an hour during the morning and evening peak periods. So rush hour rules apply from 7 to 10 a.m. and from 4 to 7 p.m. Mondays through Fridays. Terry Owens, spokesman for the District Department of Transportation, said signal engineers would adjust traffic light timings as needed.