Those commuters who traverse the Memorial Bridge on a regular basis have noticed some big changes in the traffic flow lately.

Some concern has been shown that the bridge will be closed to traffic completely, but that is not the case, according to North Dakota Department of Transportation information coordinator Mike Kopp. The bridge will remain open until traffic is switched to the new bridge sometime later next year.

The most significant changes have drastically altered traffic patterns in the past couple of weeks.

On the west side of the bridge, a portion of Memorial Highway leading up to the approach has been closed, with traffic switched to the north lane. The loop used to access northbound Expressway has been closed, as has been the offramp from northbound Expressway to the bridge.

Drivers wanting to access Memorial Highway from northbound Expressway must now use the McKenzie interchange, which is the first offramp after coming over the Expressway Bridge. At the stop, motorists need to take a left and follow over to 46th Street, by which they can reach Memorial Highway.

"If you miss the McKenzie ramp, the next place you can turn off is either Mandan's Main Street or back to Bismarck, via I-94," Kopp said. "That's bound to add an extra 10 miles or more to your trip, if you planned on accessing Memorial Highway."

On the east side of the bridge, all the turn lanes have disappeared as work begins to align Memorial Highway with the new bridge. Those coming east across the bridge and attempting a left turn onto Fraine Barracks Road have been causing some nasty traffic backups during rush hours.

"Some of our concerns have been the traffic safety and flow around the site. We've been advising motorists to find alternative routes, particularly during morning and afternoon rush hours," Kopp said. "There are no designated turns at the intersection, which is backing up traffic, more so in the mornings. But traffic habits are hard to break."

The bridge is estimated to be about 25 percent complete, according to NDDOT project engineer Doug Fercho. Basically all the substructure for the east side approach is finished and, in about two weeks, crews will start pouring the decking for the east approach.

Fercho said he looks at the project as three separate bridges - the east approach, the west approach and the center portion of the bridge.

"It's one bridge with three separate units. They have different support systems, the piers are different and it transitions from one type of bridge to another," Fercho said.

The approaches are basically concrete, while the center will be steel box girders with concrete poured on them for the deck.

"By the end of the summer, we're going to see some big changes," Fercho said. "By midsummer, they'll be setting the steel girders, and this fall, people will have a pretty good idea what shape the new bridge will take."

Traffic is expected to be switched to the new bridge sometime by late summer, early fall of 2008. At first, it will be only two lanes. Then a portion of the old Memorial Bridge, on the west side, will have to come down to allow completion of the new bridge.

Fercho said that excellent progress was made over the winter, with construction shut down only two and a half days for weather conditions.

Only one cofferdam remains to be built for pier 9 on the west side of the river near the sandbar. Next Wednesday, concrete will be poured for pier 8.

There have been some problems with boats in the area creating wakes. The NDDOT may ask the North Dakota Game and Fish Department to step up enforcement of the no-wake zone near the bridge.

(Reach reporter Gordon Weixel at 250-8255 or gordon.weixel@;bismarcktribune.com.)