A half dozen organizations play a role in designing, building and maintaining Boise's street and transportation amenities.

Ada County Highway District; Valley Regional Transit; the city of Boise and its urban renewal agency; the Downtown Business Association; and the Idaho Transportation Department have banded together and identified transportation-related improvements they are considering over the next five or so years.

Capital City Development Corp., the city's urban renewal agency, has an extensive list of planned streetscape improvements; the city is revamping the plaza in front of City Hall; Valley Regional Transit has plans to build a transit center near the Capitol; ACHD has identified one-way streets suitable for conversion to two-way; and ITD is rebuilding the Broadway bridge.

On Wednesday, the agencies are holding an open house to present some of the ideas to the public.

"We are talking about a lot of exciting things," said Matt Edmond, ACHD senior transportation planner.

Some changes will improve traffic flow, like adding turn lanes and replacing stop signs or traffic lights with mini roundabouts. Others benefit pedestrians and cyclists, like sidewalk upgrades and new bike lanes and routes.

One of the biggest changes being considered is the conversion of some one-way streets to two-way streets. The agencies have identified Jefferson, 3rd, 4th, 11th, 12th and 14th streets. Also under consideration is reversing 8th Street between Bannock and Main streets from a southbound one-way to a northbound one-way to reduce car, bike and parking conflicts.

The agencies are working together not only to better inform the public about improvements but also to better coordinate construction to minimize effects on businesses and avoid tearing up recently repaved and rebuilt sidewalks for utility work, officials say.

The agencies will review public comments gathered Wednesday and hold another open house in May or June detailing a proposed plan. The agencies are slated to adopt the plan later this summer. Construction on some of the projects may begin this fall.

Cynthia Sewell: 377-6428, Twitter: @CynthiaSewell