A recent spate of natural gas line ruptures in Bend is a reminder that even with high-tech tools to map and find utilities, excavators sometimes fail to check for gas lines before they dig — or just run into other problems.
In May, roughly 200 students and staff were evacuated from Marshall High School on NE Fifth Street after school district employees damaged a natural gas line.
The latest incident, July 10 at the Broken Top gated community in southwest Bend, did not require an evacuation.
Bend is not the only Central Oregon community to experience a series of gas line breaks. Last year, half the digging-related damage incidents reported to the state — four out of eight — were in Sunriver.
Julianne Repman, director of communications and school safety for Bend-La Pine Schools, said on Thursday that district employees thought they knew where the natural gas line was located at Marshall, so they did not call to request utility location services before excavating.
“They were working on trying to repair a leak in the main waterline to the building,” Repman said. “And they used their … drawings for the property and it showed the gas line about 75 yards away from where they were actually working, so they did not call for a locate.”
Bend Fire Marshal Larry Medina said last week that the Marshall High School gas line damage resulted from an error on the part of district employees, because they should have called 811, the phone number for the state utility notification center, to request help. The high school had been remodeled and expanded, covering the area where the gas line was previously located. Because gas lines are not allowed underneath buildings, Medina said this line was moved as part of the remodeling project.
State law requires excavators to contact the Oregon Utility Notification Center to request location services at least two days before digging. The law includes an exemption for private property, if that excavation is less than 12 inches deep and will not take place in an established easement.
Medina said the number of incidents so far this year is still within the normal range for one year, although it is unusual that the incidents all occurred within a few months.
“At Broken Top, they did all the right things — they called before they dug,” Medina said.
Instead, the gas line was damaged because the contractor was working in a location with a lot of tree roots, according to the fire department. That gas line break did not require an evacuation of nearby homes.
The other gas line incident that forced an evacuation in Bend was in March, at the site of the Oregon Department of Transportation Murphy Road project on the south end of the city. The subcontractor on the project called the state notification center, but the utility locator who checked the site did not find the gas line because it was not on the gas company’s map. Cascade Natural Gas did not have a record of this particular pipeline, which was likely installed in the 1970s and led to a vacant lot.
In Sunriver, the gas line ruptures occurred during a busy construction year. Brooke Snavely, communications director for Sunriver Owners Association, said BendBroadband was working to upgrade cable and Internet infrastructure after the company purchased the Chambers Cable System and that work was likely the cause of the first two incidents.
“There were situations where they did strike lines, whether it was they or their contractors,” Snavely said on Thursday.
According to reports that Cascade Natural Gas sent to the state, the contractors involved did call for location services but still ended up damaging the gas lines.
Snavely said the other two incidents in 2013 — both in September, on Goldfinch Lane — occurred during a Sunriver Owners Association road-paving project.
The ground is rocky in much of Central Oregon, which makes it more difficult and expensive to dig deep trenches. Snavely said these gas lines were in a shallower trench than contractors understood. According to incident reports that Cascade Natural Gas filed with the state, the contractor did request location services. The Sunriver Fire Department evacuated people from 10 homes in one incident and from 11 homes in the second.
“It turns out that the line was not nearly as deep as anybody was told,” Snavely said. “When you come back and try to repave a road and suddenly hit something that you thought was 3 feet underground, it’s nobody’s fault really.”
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