The first of 20 1,000-ton anchors was placed near the Hood Canal Bridge’s eastern half Tuesday, a job that took more than four hours.

“They finally got it to the bottom and they got it right where they needed it to be,” said Becky Hixson, bridge project communications manager for the state Department of Transportation.

The operation began at about 10:45 a.m. and was finished at about 2:45 p.m.

Hood Canal Bridge remains open while the anchors are being placed.

The floating bridge, which connects Jefferson and Kitsap counties, supports thousands of vehicles moving between the North Olympic and Kitsap peninsulas each day.

The bridge will be closed for six weeks in May and June 2009 for replacement of the aging, crumbling eastern half.

A western-half retrofit is scheduled for completion in 2010.

The first anchor was placed nearest the shoreline on the north Kitsap County end of the bridge, about 500 feet north of the bridge.

It was placed in the most shallow depth – 71 feet, Hixson said.

Other anchors will be placed as deep as 300 feet.

The DB Pacific, a large barge that can hold 2,000 tons and has a custom truss section, dropped the anchor.

Dropping the anchor involved pumping water into it to make it descend gradually.

“Three different types of sensors were used, telling if the anchor is facing bridge, if it’s level and if it’s in the right place on the ground,” Hixson explained.