In the last seven months, three blocks have shut down due to sinkholes, all because of the same pipe.
"In the late 19th century things had gotten extremely bad, the smell was horrendous, there was sewage being pumped directly from buildings like around here into the Jones falls, there were also cesspools and cesspits," Kurt Kocher with the Department of Public Works said.
Baltimore was one of the last major cities on the east coast to get a proper sewage system.
"Honey dippers as they call them would come around and essentially clean those out and haul those off," Kocher said.
Those people feared a sewer would take their jobs but a new system came, two years after a huge fire in 1904 demolished the city, paving its way.
Right in the heart of the city, a six and a half foot tall "Trunk Pipe" was put in, where smaller lines connect and head through to a sewer treatment plant. The trunk pipe spans about five city blocks.
"These were made of brick by brick and brick and mortar, so you had a circle that was formed of brick and mortar," Kocher said.
After 110 years there's going to be some wear on the old pipe, leading to cave ins underground, with soil and eventually the road filling the gap.
Back in April Centre Street was shut down. Then in July Mulberry Street caved in, and on Monday Cathedral Street was hit.
"The sulfur dioxide in the pipes is eating away at the bricks and the mortar... the green area here, Park Avenue going up to Centre Street and across this portion of Centre Street-- all this has been done," Kocher said.
Public Works cleaned then relined the sewer pipe with concrete and/or a resin mixture. Crews use the same routine when repairing any city or county pipe.
"As we're doing the immediate repairs, we're doing the whole line in between," Kocher said.
Work on Mulberry Street will last until the end of the year, and the Department of Public Works is looking into the sink hole at Cathedral Street.
"Get a TV camera in there, use other technology to see what weaknesses are in that particular line," Kocher said.
There is no estimate on when Cathedral Street will reopen, as workers have to go underground 40 feet to get to the pipe.
This fix isn't cheap, the first two repairs will cost tax payers about $11 million.
