OC Transpo said it is facing a $5.3 million budget deficit because of lower-than-expected ridership over the spring and early summer.

Fare revenue for Ottawa's transit service through the end of June was lower than expected, according to a report given to the city's transit commission on Thursday.

At the same time, ridership from April to June 2012 dropped four per cent compared to the same time period the previous year.

OC Transpo general manager John Manconi told the transit commission the drop in ridership may have been caused by more reasonable gas prices, warm and dry weather or the looming federal public service job cuts.

But Manconi said he didn't believe the drop in ridership is because of last year's service cuts.

Drop 'a natural correction': Deans

Transit commission chair Diane Deans framed the decrease in ridership as a "natural correction" after what was a banner year for ridership last year.

"It was almost inexplicable as to why our numbers were so high last year, so levelling off a little bit was not completely unexpected," said Deans.

Neither Deans nor Manconi were talking about more service cuts for 2013 to make up the deficit shortfall. Transit commissioner Blair Crew also said that option is not on the table.

"It's simply not viable, it's a service we need to provide, and I'm not in favour of any further route cuts," said Crew. Manconi said he will keep an eye on the current quarter's numbers, to see if a trend is forming.

In the meantime, OC Transpo can draw on a contingency fund to cover any short-term loss.