Public meetings held late last year are helping Ulteig Engineers focus their study on the north-south routes of the eventual beltway that will surround Bismarck, Mandan and Lincoln.

Ulteig representatives met with Burleigh County and Lincoln governing groups last week to discuss the north-south route possibilities east of Bismarck.

The study is now looking at 80th Street and 66th Street as separate routes, rather than possibly combining them with crossover roads. Also, 84th Avenue is being added to the beltway mix along with 71st Avenue as a possible north east-west route.

"We were asked at the Bismarck meeting why we weren't looking at 84th, so we added it," Uteig's Steve Windish told the Burleigh County Commission.

While 84th does not align with the bridge proposed in the Northern Bridge Corridor study, it does have some advantages over 71st Avenue/Highway 1806 with fewer access points and waterway crossings.

Windish said that fewer access points to a route allow the traffic to move safer, more efficiently and faster. Also, bridges are expensive features, so the less you need the better. Because there are fewer access points on 66th, there are longer stretches which will allow speed limits of 45 to 60 mph.

A comparison of 80th Street and 66th Street shows:

n Access points: 66th Street has nine north of the interstate and 39 south. 80th has 19 north of the interstate and 47 south.

n Waterway crossings: 66th has none north of the interstate and three south. 80th has one north of the interstate and three south.

It will take time to develop the beltway as its construction follows development, and it likely will be a piecemeal approach. While it may be many years before the beltway is complete, it is important to make choices now to allow jurisdictions to secure needed right of way and allow development of an interchange on the interstate, Windish said.

There's an interstate overpass on 80th Street, but it will likely be torn down rather than incorporated into an interchange if that route is chosen. The existing infrastructure is neither wide enough or strong enough to support the expected traffic, Windish told the Lincoln council.

If 80th Street is the selected route, it likely will preclude an interchange ever being built at 66th Street because of federal uniform interchange spacing guidelines, which call for at least two miles between interchanges - the two streets are within a mile of each other.

Cost studies haven't been conducted yet, and further research on how much roadway actually exists on the routes along with bridges needs to by considered. Also, the study will look at wetland mitigation and what those costs will be.

Construction of an interchange will take at least one construction season. Along with bridges, the plan also will look at railroad track overpasses for both 80th and 66th.

The study won't be complete until late spring 2009, at which time the approval process will begin with hearings among the various government jurisdictions. The study hopes to identify short-range needs, along with things to be done in the next 10 years, 20 years and outside 20 years. It could take up to 50 years until the beltway is completed.

Another public input meeting is being planned for this summer.

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