WASHINGTON — If you’re thinking about driving across the Chesapeake Bay Bridge this Sunday morning and afternoon, you might want to think again.

Drivers will experience significant traffic delays throughout the day and early evening, officials warn. To avoid those delays, motorists should drive the bridge prior to 6 a.m. or after 6 p.m.

Nearly 20,000 runners are supposed to run across the overpass in this weekend’s Across the Bay 10K, the first ever race of its kind. The runners will gallop 6.2 miles from Northrop Grumman on the Western Shore to Chesapeake Bay Business Park on the Eastern Shore from 7 a.m. and 2 p.m.

As a result, the bridge’s eastbound span will be closed to traffic from 2 a.m. to 2 p.m. Two-way traffic will be opened on the westbound span.

While the center lane will mostly be closed, it may open occasionally to help reduce westbound delays.

The off-ramp from U.S. 50 eastbound to Md. 8 will be closed during the event. A detour will be in place to direct drivers to the next exit at Thompson Creek Road.

From there, motorists will travel westbound on Md. 835 to the signal at Md. 8. The on-ramp from southbound Md. 8 to westbound U.S. 50 will be closed during the race.

Drivers attempting to access westbound U.S. 50 will be directed to Md. 18, to the roundabout at Castle Marina Road and onto U.S. 50 west.

Pedestrians aren’t allowed across the bridge that often. In 2004, three years after the Sept. 11 terrorist attacks in New York, Virginia and Pennsylvania, the Bay Bridge Walk took place under heightened security.

A year later, the walk was canceled due to construction and the high cost of providing security for the event.

The walk, which would draw 40,000 people to the bridge, hasn’t happened since 2005. It was first held in 1975.

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