Workers from the Greater Pottsville Area Sewer Authority recently tore out a section of the 19th century stone sewer works near the 500 block of North Centre Street and replaced it with a new pipe and catch basin.
"I'd say we pulled about 300 ton of stone out of there," said Vince Riotto, the street crew supervisor, who was overseeing the work Thursday.
The stone arch combined stormwater and sewer system, which has been causing city and sewer authority headaches as heavy rains have broken sections down.
"It's the excess rain. If you see how they're made, there's no mortar in them. They're made of mountain stone, and they don't wear out. But heavy rains can push the stones out of place," Riotto said.
"It's just been a rough couple years on the system," Timothy R. Yingling, the sewer authority's executive director, said Friday.
Built over three streams which flow into Norwegian Creek, it's a major part of the city's infrastructure. And the authority will continue to use it for years to come indefinitely, Yingling said.
"It'd be too expensive to replace all of it at once," Riotto said.
The cost to abandon it and construct new sewer lines would be in the neighborhood of $60 million, Yingling said.
"To do that, you'd have to either get a PennVEST loan or a bond issue and then that would raise the sewer rates," Yingling said.
Amanda Witman, a spokeswoman for the state Department of Environmental Protection, Harrisburg, said the state expects the authority to do its best to manage the system, but not perform miracles.
"It would be excellent if municipalities could afford to replace these systems, lock, stock and barrel. But given the financial realities of our time, they are bound to monitor and remediate problems as they arise," Witman said.
Problems with such systems are inevitable, Witman said.
"They are quite durable because of the materials they're made from," she said. "However, it's important to know that because of the design, if one stone falls, it's likely a row of them will fall, too."
"Our concern is it's really old infrastructure. It's important infrastructure. And it needs attention, like anything else," City Administrator Thomas A. Palamar said.
Jon C. Schladweiler, a retired engineer from Tuscon, Ariz., and historian for the website www.sewerhistory.org, said since sections have been collapsing, the authority should make efforts to inspect the system if possible.
"The key is they have to inspect them if they're going to be maintained over the years. Each type of sewer, depending on what it's made of, will degrade over time. You have to monitor what's going on. But it's not the easiest thing to monitor these sewers," Schladweiler said.
However, the sewer authority doesn't do regular inspections.
"It's just not feasible," Riotto said.
The authority is low on manpower. It employs four street workers, and two have been out on workers compensation, Yingling said.
"Right now we know where there are certain problem areas and our staff does try to inspect those areas, but we don't have the manpower to be constantly looking at it," Yingling said.
Some sections are difficult to see into. "You can't get into the small ones," Riotto said.
But experience has shown the authority where future problems may occur, the area where gravity sends rushing stormwater.
"Most of it is downtown," Riotto said.
Recent incidents
There were two recent incidents downtown.
On June 10, a section under the former Harrison Street broke during the heavy rainstorm, sending dirt and raw sewage spilling onto the 500 block of North Centre Street.
The 200-foot stone chute carried storm and sewer water from homes on North Second Street down the hill. Heavy rains broke through it on June 10, flooding the 500 block of North Centre Street
On Thursday, the remains of that old stone arch were sitting on a pile just off the 500 block of North Second Street.
The Greater Pottsville Area Sewer Authority hired Dallago's Backhoe Service, Minersville, to repair the system, according to Tom Dallago, Pottsville, Dallago's vice president.
Dallago's installed a 24-inch ADS-brand pipe, Dallago said.
The stone arch was replaced by new pipe which was covered by 216 tons of "2B stone," Riotto said.
"We don't know the total cost of repairs yet. The work is still being done," Yingling said.
On July 3, a section of the arch repaired in 2011 on East Market Street gave way. On July 8, workers from Mazzuca Enterprises Inc., Pottsville, replaced it with 80 feet of 48-inch diameter plastic pipe.
The sewer authority will discuss the cost of that job at its next meeting, slated for 7 p.m. Wednesday on the third floor of City Hall, 401 N. Centre St., Yingling said.
The authority isn't taking any additional steps to inspect the system, "other than to respond to when we have breaks in it," Yingling said.
Since the breaks were caused by storms, the City of Pottsville has applied for state or federal funding to support the authority's repair work, Palamar said.
"There's a possibility we could get money to pay for repairs we had to make, because both the city and the sewer authority had expenditures there. They had a majority of it, but we had to pay some overtime to have our crews out cleaning up the wash out that came off Harrison Street onto Centre," Palamar said.
History
The local system is akin to those developed after the fall of Roman Empire, Schladweiler said.
"Around the year 1100, a lot of the people after the fall of the Roman Empire in Europe began to live in small, walled cities. They were building houses and they were running out of space. About the only areas that weren't built upon by houses were the drainage areas, rivers or creeks. So they decided to structurally cover these areas with arch-type structures, then they covered the arches with dirt and on top of the dirt they built more houses. Unknowingly, they were also learning how to build structures to convey water, stormwater, sewage, what have you," Schladweiler said.
Over the years, communities in Europe used this method to develop storm and sanitary sewage systems.
"In Pennsylvania, I don't know when these sewers were built, probably the 1800s or somewhere around there," Schladweiler said.
In 1806, John Pott, a native of Oley, Berks County, bought the land on which the City of Pottsville now sits. Pott started to lay out the community and subdivide it into lots and the city was born.
Yingling wasn't sure when the stone arch system was built.
Witman said DEP engineers believe it was about 1850.
"It was created before public records were kept on that sort of thing," Witman said.
The first written record of the system DEP had in its Harrisburg office was a 1930 map of the City of Pottsville.
"People would use the talents that were available to them, materials available to them and conditions available to them, especially in smaller communities that didn't have money. They knew they needed sewers but didn't have money to go buy things, like pipe from a factory 200 miles away," Schladweiler said.
The combined sewage and stormwater collection system was built over streams which wove through the city and drained into Norwegian Creek.
"I don't know if these streams were named," Yingling said Friday while reviewing the 1930 map Witman was referring to. On it were thin blue lines with the word "sewer" below them.
"That's why the system weaves through town. It's the streams. All they did was encase them. They didn't mess with them otherwise," Riotto said.
"Combined systems in the early days were almost always made on the quick. What kind of stone was used to build these drains? Was it granite? Or limestone?" Schladweiler asked.
"It's mountain stone. They don't wear out. And these aren't just rocks. The stones were cut and carefully placed. I figure they must have had some kind of a form. You see how nice and round some are. You can't do that with your eye. And it was dry set. What holds them in place is a keystone. It's a work of art," Riotto said.
While some sections are 3 feet wide, like a strip on the south side of the Schuylkill County Courthouse, other sections are larger, like one which runs under the Pottsville Free Public Library.
"It's 6-foot round. You can drive a Volkswagen through it," Riotto said.
The practice of building stone-arch sewers in the United States faded out in the late 19th century, Schladweiler said.
"When you got into the late 1800s or early 1900s, communities started using other materials because they had the machinery available to transport and install precast pipe in larger diameters," Schladweiler said.
The Greater Pottsville Area Sewer Authority serves the City of Pottsville, the boroughs of Port Carbon, Palo Alto, Mechanicsville and Mount Carbon and portions of the townships of Norwegian, North Manheim and East Norwegian. Its entire system is 68 miles long, according to the authority's website at www.gpasa.net.
Yingling did not know how long the system was in the City of Pottsville, but said it serves 5,241 units.
It's a "combined sewage and stormwater collection and conveyance system, which includes 6-inch through 60-inch pipe and a number of various stone arch conduits," according to the authority's site.
"The system is a combined storm and sanitary sewer system consisting of collectors and interceptors ranging in size and material. The portions of the system installed after 1972 are generally in good condition, and the older stone arch culverts are in varying conditions of repair requiring regular maintenance and rehabilitation," according to the site.