LITTLETON — A methane-fueled fireball hurls manhole covers hundreds of feet, like giant circular saw blades slicing the air. A pipe more than 60 years old collapses 50 feet underground, causing millions of gallons of raw sewage to back up until the noxious stew flows into the South Platte River.
It’s a disaster that hasn’t come to pass yet, but sanitation officials in the south suburbs say the doomsday scenario is “not beyond the realm of possibility.”
“This is something that has to be dealt with really quickly,” said Platte Canyon Water & Sanitation District manager Patrick Fitzgerald.
Fitzgerald spoke to a room of concerned residents this week, trying to raise awareness about the condition of a sewer main that lies beneath an abandoned dump at the southeast corner of West Oxford Avenue and South Clay Street, where high concentrations of explosive methane generated by decomposing material can infiltrate the pipe. Installed in the mid-1950s, the 24-inch diameter concrete pipe carries nearly 900,000 gallons of sewage each day to the Littleton/Englewood Wastewater Treatment Plant from 2,200 customers living in Denver, Sheridan, Englewood and Littleton.
Fitzgerald’s message — we risk disaster if we do nothing about this pipe and where it’s located — seemed to be getting through to those in the audience.
“This is an important issue that we need to address,” said Rosanne Henry, who has lived in Littleton for 33 years.
Henry recently received a postcard in the mail from Valley Sanitation District with a dramatic headline in large red font: Exploding Sewers! Valley Sanitation District needs your help to avoid catastrophic sewer failures.
It got her attention — and the attention of about 20 of her neighbors, who turned out at Columbine United Church in Littleton for a public meeting on the issue Wednesday night.
The pitch: Valley customers will likely be asked this November to raise their property taxes an average of several hundred dollars a year to cover the $2.3 million cost of moving the sewer main out of the landfill. The fix is expensive because the pipe is buried under 50 feet of trash and nearly impossible to access at this point, Fitzgerald said, so a new pipe would have to be installed.
Dianne Smith, who lives in the Denver portion of Valley Sanitation District’s service area, said she knows the prospect of a higher tax bill won’t sit well with many in the district, but she shudders at the thought of dealing with a sewage backup or a methane blast near her home.
“If there’s a leak or an explosion, it would quadruple the expense in the end,” she said.
The problem was first detected last year, when workers at the Littleton/Englewood Wastewater Treatment Plant got high methane readings at the plant’s headworks. They traced the origins of the gas to an 1,800-foot section of pipe underneath the old landfill, about 2 1/2 miles upstream from the plant.
“We’re concerned about it because we’re getting significant levels at our facility and we don’t want an explosion here,” said Dennis Stowe, director of wastewater treatment for Englewood. “We would like to see it get taken care of.”
For now, Stowe has pulled his crew from taking any more readings at the landfill site “out of an abundance of caution.”
“There’s the potential of a huge explosion when the manholes are being opened up,” he said, be it from a dropped cigarette or a metal-on-metal spark.
Platte Canyon Water & Sanitation District supervisor Scott Hand also won’t let his crews onto the landfill site anymore. Platte Canyon manages operations for Valley Sanitation District.
“At some points, (methane readings) were 100 percent explosive,” he said. “We’re concerned if a spark was introduced, methane is very flammable.”
The Colorado Department of Public Health and Environment is aware of the situation but so far has not received data or evidence that there has been a methane release at the site that is “above the current standard,” according to spokesman Warren Smith.
“While the presence of methane is not good,” he said, “it does not create an imminent hazard for an explosion.”
A blast would necessitate the right mix of methane, oxygen and an ignition source, Smith said, which at this point constitutes a “speculative scenario.” But if sanitation officials wanted the department to take a closer look at the situation, he said they would.
As far as getting money for a relocation of the sewer main, the age of the landfill and the fact that it predates state environmental regulations from the early 1990s that speak to methane levels make it difficult to squeeze remediation funds out of anyone. But Smith said Valley Sanitation is free to apply for a low-interest loan from the agency’s Clean Water Revolving Loan Fund to help pay for the work.
Fitzgerald said this week that is what the district plans to do, but taking on that kind of debt would still have to be approved by voters. He said the district has about $450,000 in reserves versus about $3.4 million in maintenance costs across the system, which includes 27 miles of sewer pipe and 565 manholes.
Paying more for sewer service is something Denver residents , when City Council passed a large fee hike. But customers in the city will be hit with an average $116 increase in fees over five years as opposed to a couple of hundred dollars a year, as is being proposed in the Valley Sanitation District. Firm numbers for a yearly tax increase have not yet been hammered out, Fitzgerald said.
Fitzgerald and his colleagues are exploring whether to track down the owner of the former landfill and see whether money can be found there, but he told attendees of Wednesday’s meeting that the owner and state and federal authorities appear to have capped the dump and arrived at a settlement on contamination years ago.
“We think the best thing is to get a loan and have the customers pay it back over 30 years,” he said.
Two more meetings on sewer repair
7 p.m., March 20 — St. James Presbyterian Church, 3601 W. Belleview Ave., Littleton
6:30 p.m., April 12 — Centennial Academy of Fine Arts Education School, 3306 W. Berry Ave., Littleton
