On track to clear pipes of decades of gunk

drains, and use modern mapping software to pinpoint their whereabouts. The system will help managers determine how often each drain needs to be cleared and which spots are most prone to clogging.

“Now we’re doing a sampling program that tracks how silt and debris affects different key [drain] boxes so that we can put effective cycles in place to maintain these improvements,” said Librera.

Some gunk flows from the 46 miles of underground “ballasted” track that sits on gravel instead of concrete. Some of it seeps through old tunnels beneath the water table and have a 100-year-old waterproofing syssubway tem comprised of brick and tar. Trash thrown from platforms also helps clog drains.

The MTA has sent bags of dirt to labs in hope of learning more about where it comes from.

Cleaning out gummed-up drains is a big task. The Daily News recently watched one cleanup that required crews to shovel gunk into 25 sandbags before they reached the drainpipe. The team then finished the job with a giant vacuum rigged up aboard one of the agency’s work trains. The MTA’s vacuums are big — but they don’t always fully work.

One of the hoses last week could not pull out a thick chunk of silt and rock. Workers had to wait around for an hour while the problem with the vacuum was fixed.

A few drains are so densely clogged crews must clear them with a jackhammer. Sometimes, workers must replace entire sections of mucked-up pipe.

Roughly three-quarters of the drain maintenance work completed under the Subway Action Plan was done by private contractors, said an MTA source. Union officials agreed to that arrangement as a one-time deal in what Samuelsen said was “the spirit of getting the subway back into a state of reliability.”

It’s unclear who will mainpart tain the drains moving forward. TWU Local 100 is in the middle of contract negotiations with the MTA, and drain work is a of those talks.

The MTA will have money to continue to pay for drain maintenance and other essential upkeep. Some $300 million will be allocated to the Subway Action Plan each year, thanks to a surcharge on taxis and for-hire vehicles that went into effect in February.

It’s more important than ever for the MTA to keep the subway dry. NYC Transit President Andy Byford is preparing to speed up trains by rapidly upgrading the subway signal system with equipment that is not waterproof. “Signal systems are sensitive to water,” said Keating. “No doubt that’s something you want to invest in — keeping water out to protect the equipment.”

But history shows that subway managers will have to take care the drain system does not lapse again into disrepair.

“The concern for everyone is what’s going to happen in future years,” Keating said.

“We might go back in five years and find out the drains are clogged. They’re going to make promises right now, but the pattern we have observed too often is that we have to continually monitor progress or it will slide right back.”