A Portland working group began exploring on Wednesday the benefits and drawbacks of converting State and High streets to two-way traffic in response to concerns about pedestrian safety on two busy arterials through downtown.

Leaders of the first meeting of the State and High Streets Project Advisory Committee told committee members that they should set aside any preconceived notions about whether the streets should remain one-way or opened to two-way traffic.

“Listen to the facts,” said Carol Morris, a consultant helping to coordinate the working group’s efforts. “Nobody knows what it is going to work and what is not going to work.”

State and High streets have been restricted to one-way traffic since the 1970s and are popular thoroughfares for drivers passing between Interstate 295 and the Casco Bay Bridge, although the city has attempted to divert some of that traffic to the Fore River Parkway. Some neighborhood residents and cyclists complain that many drivers on State and High exceed the 25 mph speed limit, making it dangerous to cross or ride a bike on the roads.

At least seven intersections along State and High streets on the peninsula were rated as “high crash locations” between 2011 and 2013 when compared to statewide averages, according to data supplied to the committee. They included where Park Avenue intersects both streets, as well as the larger intersection of State Street, Forest Avenue and Marginal Way. Additionally, eight block segments were rated as “high crash locations,” although Tom Errico, with the engineering firm T.Y. Lin International, said many of those were related to parking or sideswipes.

Over the next nine months, consultants will work with the city and the advisory committee to study the issue before making a formal recommendation to the City Council. The committee, which contains representatives of business and civic groups, as well as government agencies, plans to evaluate how the change would impact travel times through Portland as well as traffic volume.

Committee members listed a number of potential benefits of switching to two-way traffic, including lower average vehicle speeds, increased visibility for businesses along the corridors, improved connectivity among parts of Deering Oaks Park bisected by the road, and allowing drivers to take more direct routes to some destinations.

Also, members said two-way traffic could reduce the risks of car-pedestrian incidents in crosswalks. Under the current configuration, pedestrians can be obscured by the first stopped car as they approach the second lane.

One of the top concerns raised by several committee members – including representatives of local churches and the Westin Portland Harborview Hotel – is that reverting to two-way traffic would likely result in the loss of some on-street parking. In some cases, parking spaces near intersections may have to removed to provide additional space for turning traffic.

Other potential drawbacks of two-way traffic identified by committee members were increased congestion along the two corridors, additional traffic on nearby streets as drivers seek to avoid traffic, snow removal challenges and the possibility of head-on collisions.

Portland’s re-evaluation of State and High streets is part of a national trend as city planners convert the traffic flow on major one-way streets to two-way traffic in an effort to make downtown areas more pedestrian- and cyclist-friendly. Portland officials are also in the midst of several other studies evaluating potential changes to Congress Square, Spring Street, Franklin Street and the Commercial Street and High Street intersection – among others – that could affect any decision on traffic flow on State and High streets, Errico said.

The city plans to hold a public forum on the topic in September or October to gather feedback from local residents on the potential conversion to two-way traffic. The committee hopes to report its recommendations to the City Council by April.