PROVIDENCE — Since the closure of the westbound side of the Washington Bridge, it’s not only cars that have been stuck in the resulting traffic backups on Interstate 195 — buses have, too.

Some lines that usually travel over the bridge (24, 35, 61X, 78) are arriving late more frequently now that the bridge is partially shut down. (The 60 also goes over the bridge but hasn’t seen an increase in lateness.)

In September through November of last year, those routes, excluding the 60, were late less than 24% of the time on average. Then, in December, when the bridge closed, those buses were late about 30% of the time. Punctuality decreased again in January, and lateness rose above 39%.

The 60 was the only bus to travel over the bridge that hasn’t seen a decrease in on-time performance. Its lateness has remained below 20% since last September even after the bridge closure, falling in line with the Rhode Island Public Transit Authority’s overall on-time performance.

According to recent reports, RIPTA’s fixed-route service’s on-time performance hovers around 79%.

“As expected, our on-time performance was impacted by the Washington Bridge construction, particularly in the early weeks of the bridge closure,” RIPTA spokesperson Cristy Raposo Perry wrote in an email to ecoRI News. “With the progress made, including the opening of a third lane in both directions on the Washington Bridge, we are hopeful that travel times will decrease.” (The third lane opened at the end of April.)

Of the buses that cross the bridge, Route 35, which travels between East Providence and Providence, saw the most drastic on-time performance change. In November, buses in that line were late an average of 20% of the time. But last month, they were late almost half the time.

Both the 35 and 70 are avoiding the bulk of the I-195 traffic on their inbound trips, according to Raposo Perry, by using the Henderson Bridge, but outbound trips are following their typical patterns.

Warren resident and RIPTA rider Allison Montagnon said she has seen a difference in service when she spoke to ecoRI News in March.

“I definitely missed more than one connecting bus in Kennedy Plaza because the bridge traffic took longer than anticipated,” she said.

Advocates and riders have floated the idea of using RIPTA to try to solve the traffic issue by reducing the number of cars on the road.

When asked about whether a bus lane or more service going between Providence and East Bay could be added, Raposo Perry said: “Unfortunately, due to our driver shortage, we are unable to add bus service.”

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