“If we could mine this stuff, we’d be pretty wealthy,” a sanitary manager quipped today as workers extracted the largest known lump of congealed grease, fat and assorted detritus yet found in Baltimore’s sewer system.

The Department of Public Works summoned the media to Charles and Lanvale streets to witness the breakup of the crusty, sticky mess (looking sepulchral white on closed-circuit TV) that’s been clogging a vital sewer main in Charles North.

The buildup had reduced the flow of sewage to a trickle, causing raw waste to flow into the Jones Falls on three separate occasions since September 14.

Those spills totaled 1.34 million gallons, all in technical violation of the city’s consent decree with Maryland and federal environmental agencies.

Another 1.25 million gallons of sewage flooded at the same underground location between April and September, DPW records show.

Jeffrey Raymond, spokesman for the agency, told reporters that the city found out about the blockage just a few weeks ago.

Another official said this particular “fatberg” had likely been growing in size and stature for the last half century. (The phenomenon became famous in 2013 when similar blobs were discovered in Chicago and in London’s Victorian-age sewers.)

“My guess is it took decades – 50, 60 years,” said Pat Boyle, a DPW pollution administrator, describing how the fatberg reached its present size, estimated at 20 feet.

Asked what it consisted of, Boyle said, “Anything you might use for cooking – grease, butter, mayonnaise. Anything your grandmother said, ‘Don’t put down the drain.’”

Restaurants Are Violators

DPW analyst Vib Patel said about two-thirds of the grease and oil that flow into the city’s sewer pipes comes from private residences and the remainder from commercial food establishments.

Currently 38% of the city’s restaurants and carry-outs are not in compliance with sanitary rules regarding the disposal of unused grease, Patel said.

Non-compliance has dropped slightly since DPW initiated its FOG (congealed fats, oils and grease) Program and licensed restaurants with wastewater discharge permits.

When FOG started in 2013, about 20% of food establishments lacked grease control devices, Patel said. That number is down to less than 1% today.

Even so, poor maintenance of grease traps and inadequate instructions to staff mean that nearly 4 in 10 Baltimore food establishments are still co-conspirators in potential plug-ups.

“Basically, we’re creating soap when we create a fatberg,” Boyle said, with the big asterisk that the resulting blob befouls rather than cleanses.

In the warm belly of Baltimore’s sewers (a balmy 68 degrees year-around), fats and lye make soap, a process known as “saponification.”

The accumulating “soap” becomes a natural habitat for many undesirables, trapping not just fecal material, but diapers, wet wipes, tampons, dental floss and other things that people flush down toilets.

Today, technicians from TFE Resources blasted out such debris with high-pressure hoses and vacuum pumps.

The dissolving mass let itself be known by the foul scents that rose up along Lanvale Street. The slime will be taken away by trucks to a city landfill for burial, Raymond said.

If citizens don’t want to read future stories about saponified fatbergs, “then we can’t treat our toilets and sinks like trash cans,” Boyle added.

HOUSEHOLD TIPS FROM DPW:

• When cooking, pour all unused grease “from the pan to the can.” Once it solidifies in the can, put it in the trash.

• Do not flush tampons, wipes, diapers or dental floss down the toilet. The only flushable consumer product is toilet paper.