When boating season opens, so do the bridges. With the 2014 season kicking off this weekend, drivers should expect additional delays on both the State Route 520 Bridge and the State Route 513 Montlake Bridge.

The Montlake Bridge will close to vehicle and foot traffic from 10 a.m. until 4 p.m. on Saturday to allow about 900 boats to sail through the Cut as part of Opening Day of Seattle’s boating season.

During the bridge closure, crews will also close the westbound SR 520 off-ramp to Montlake Boulevard and the left-turn lane of the eastbound SR 520 off-ramp to northbound Montlake Boulevard.

A special opening of the east navigation channel beginning at 9 a.m. on May 1, to accommodate vessels up to 59 feet tall will lessen traffic impacts for drivers on the SR 520 floating bridge this weekend. WSDOT will keep the channel open until just before midnight on May 4.

Boaters will notice changes to the west navigation channel as well. A newly placed pontoon on the west side of Lake Washington has required the west channel to be narrowed from more than 200 feet wide to 120 feet.

Drivers will see frequent openings of the SR 520 drawspan again this summer due to Coast Guard rules requiring the Washington State Department of Transportation to open the bridge for boats more than 45 feet tall. Marine openings of the SR 520 Bridge are prohibited Monday through Friday from 6:30-10 a.m. and 3-7 p.m., except on federal holidays excluding Columbus Day.

In addition to electronic highway message signs advising drivers of an SR 520 opening, text and email alerts provide a two-hour notice.

WSDOT also keeps the east navigation channel open on Memorial Day weekend, Independence Day, Seafair weekend and Labor Day weekend. The floating bridge’s west navigation channel is always open.