Following a track fire that crippled subway service last week, MTA vice chairman Fernando Ferrer is concerned about an apparent lack of enforcement of littering laws.

The police department has issued 79 summonses, which carry a $50 fine, for littering so far this year, according NYPD Transit Assistant Chief Vincent Coogan.

That number worries Ferrer.

“Seems to be a very small number of summonses for a very large problem,” said Ferrer, who added litter “too often brings hazardous conditions that can lead to a fire.”

Debris at the switch area near the 145th Street station in Harlem sparked the blaze on the Eighth Avenue line on July 17, resulting in a shut down of the B and C lines and partial suspension of A and D train service for more than two hours during the morning commute.

Coogan reasoned that the small number of summonses issued is because commuters tend to refrain from littering in front of police at stations.

“Most people would not litter in front of a uniformed officer, I wouldn’t think. But when we do see it happen, we do issue a TAB (Transit Adjudication Bureau) summons,” said Coogan. “So we don’t ignore it. We do issues summonses for it.”

There were 698 track fires since July of last year, which is far fewer than the roughly 5,800 that had accrued through the same time period in 1981, according to the MTA. But fires have a ripple effect, causing many delays through the subway system, the MTA said. Fires logged in May of this year caused 984 delays, according to MTA data.

Wynton Habersham, the head of the subways department at the MTA, said the agency has begun paying more attention to areas where trash usually builds up.

“While litter proved to be the root cause of the incident,” Habersham said, “we have directed staff to give more attention to debris located in switch areas outside of the station, where debris tends to accumulate.”