Although thousands of riders will be affected when the Port Authority makes radical changes to bus and trolley service next year, only 26 of them showed up in Carnegie yesterday for the first of seven "open house" meetings to discuss their transit concerns.

Authority officials said they weren't discouraged by the small turnout for the informal "Tell Us Where to Go" session.

Service planning manager Peter S. Behrman said scores of such meetings will be held to seek input before a preliminary transit restructuring plan is drawn up.

Then, the "Connect 09" plan will face public scrutiny at government-mandated hearings.

"Basically, we're asking people, 'If it means more frequent service, are you willing to transfer, or do you want a one-seat [through] ride with less service?'" he said. "We have a set amount of money to spend on public transit and we need to spend it wisely. We can no longer have everything."

The plan that the authority says is designed to match service to demand, and do it more cost-effectively than in the past, is to be implemented in phases starting late next year.

Riders at the Carnegie meeting were divided over service options, but their feelings were clear about other matters, including providing more park-and-ride spaces, adding service to Oakland and cutting down on the number of "pass-ups" on routes like the West Busway because of overcrowding.

The authority has already begun to make changes like those. It restructured 33F McDonald Express buses and made riders transfer on the West Busway in 2006 and, last year, it restructured three Mt. Lebanon-area bus routes and operated them as "feeder service" to the light-rail line.

"These open houses are an opportunity for riders to tell us what's important to them and to give us their ideas," Mr. Behrman said.

The next meeting will be at 5:30 p.m. today at the Murrysville Municipal Building for riders in the eastern suburbs.

"Connect 09" information can be found at tdp.portauthority.org.