T ridership hits record high

The MBTA attributed the latest record to simpler, if similar, reasons: Job numbers are up, so more people need to get to work. But gas prices remain high, so more of those commuters are opting for mass transit. The unemployment rate in Massachusetts last month approached a three-year low, while the cost of gas, though down from a spring high of $4 a gallon, remained well above 2009 and 2010 prices.

The high-water mark for transit use came as the T contemplates a fare increase and service cuts that could take effect next summer, hoping to close a projected $161 million deficit for the coming year.

“I’m real concerned … because we could take what is obviously a very important and significant trend and pull the rug out from under it,’’ said Richard A. Dimino, president and chief executive of A Better City, a planning and advocacy organization that represents hospitals, universities, financial firms, and other major employers on transportation issues. “The T is the workhorse for the Massachusetts economy.’’

September is often the busiest month on the T, when college students flood Boston and employees return from summer vacations. Average weekday ridership in September exceeded the previous September by 4.3 percent. It was also the eighth straight month in which the T recorded growth compared with the year before.

All modes showed increases in September over the previous year, bolstered by 5.6 percent growth on the heavy-rail subway lines (Red, Orange, and Blue) to an average of 550,100 riders each weekday, also believed to be a modern record. Ridership on light rail - the Green Line and Mattapan trolley - grew 3.6 percent, to 244,900. Bus ridership grew 1.8 percent, to 388,300. Commuter rail riding grew 3 percent; ferry service, 6.4 percent.

Waiting for the Red Line at Park Street Station, art student Antonio Harris of Brockton said he has seen the growth firsthand since he began commuting during the depths of the recession. Harris, who rides the commuter rail, subway, and Green Line to school in Brookline, said he has noticed a particular crush during peak hours on the Red and Green lines.