Underground leaks may be gassing trees

August 10, 2007
By

David Taber


Courtesy Photo Arborway resident Kevin Handly says he suspects the lack of foliage in the area immediately adjacent to a gas leak between 59 and 61 Arborway is the result of the soil being saturated by natural gas.

PONDSIDE—While not incendiary or a health threat to humans, leaky underground gas lines may be choking trees along the Arborway, according to experts.

Faced with a 100-year-old tree-stock reaching the end of its natural life along the Emerald Necklace, the Department of Conservation and Recreation’s (DCR) has been planting both young and mature red oaks on the Arborway over the last few years, with limited success.

Meanwhile, Arborway residents say they have been smelling gas leaks and reporting them to Keyspan, which owns and maintains the lines, for years. On an early morning walking tour with Arborway resident Kevin Handly, the smell of gas was distinct at one location, near a stone pillar between 59 and 61 Arborway.

“This strip is completely without trees and it is a problem area for gas,” Handly said, pointing out that there are no trees for about 30 feet in either direction from the leak at 59-61.

Handly said he also regularly smells gas across the street in front of 62 Arborway, at the northwest corner of Arborway and Pond streets, and on the northeast corner of Arborway and Centre.

The strip that runs past 62 Arborway is also devoid of trees, although there are a number of patches on the tree lawn between the street and the sidewalk where it appears trees were planted. Keyspan was able to confirm to the Gazette there is a low-level, or grade three, leak at the corner of Arborway and Pond and a mid-level, grade two leak, recently upgraded from grade three, at 59-61. Emergency repairs were conducted at both locations in December 2006, said Keyspan spokesperson Carmen Fields.

Grade one leaks are dealt with within an hour, Fields said.

The Pond Street leak is being monitored, which is all that is required for grade three leaks. Grade two leaks are required to be repaired within 14 weeks of detection, and, as of Aug. 1, the 59-61 leak was scheduled for repair “in the next few days,” Fields said.

On Aug. 6, Handly sent the Gazette an e-mail saying he smelled another “strong” leak at 3 Arborway. “This is an historic gas hotspot-gas killed an adolescent oak here two or three years ago,” Handly wrote.

Although Fields could not confirm it, Arborway resident Sarah Freeman said a number of leaks were fixed in 2004 when the DCR was transplanting a number of mature trees onto the parkway.

In late July, DCR spokesperson Wendy Fox said it was her understanding that all of the leaks had been fixed at that point.

The Gazette previously reported 20 young red oaks the DCR planted on the Arborway last summer had not taken and were slated for replacement this year. Some, thanks to regular watering by DCR crews, are still alive, but a number of the new trees are not.

Fox told the Gazette five percent of the 150 red oaks the DCR planted across the city in the last 15 years have survived, citing environmental factors as the reason a tree species that managed to survive along the parkway 100 years ago is no longer able to take.

Despite their poor survival rate, DCR is required to plant red oaks by the Boston Historic Commission (BHC). The existing stock of red oaks along the Emerald Necklace were planted in 1911 as part of the original park design and are reaching the end of their natural lifespan.

Richard Schulhof, deputy director of the nearby Arnold Arboretum, said the only two significant factors in establishing new trees along the Arborway are irrigation and soil contamination.

“If you have a gas leak saturating the soil, it causes a lack of oxygen which affects root function,” he said.

A major leak could be killing the trees, Schulhof said, but further investigation would be needed.

If a leak is plugged, the gas in the soil will dissipate naturally, so no remediation is necessary, Schulhof said.

The red oaks on the Arborway may have a new advocate in state Rep. Jeffery Sánchez. Sánchez [and the Gazette] were introduced to the theory that gas leaks are killing Arborway trees by Arborway resident Ed Zawaki at a community meeting the State Rep. hosted in late July.

An aide in Sánchez’s office said they contacted Keyspan about looking into leaks on the Parkway, but had not yet had a follow up conversation.

They had not yet determined how they would proceed if Keyspan’s leaky pipes are killing trees, she said.

In an interview, Zawaki said he thinks, given that gas leaks seem to be a chronic problem along the roadway, Keyspan should dig up the pipes and line them with plastic.

Or else, “ Why not put up plastic trees and change them according to the season?” Zawaki said.

That might at least be more cost effective than what he suspects is going on now. “One agency is working hard to put in trees and another agency, the gas company, is not repairing the lines,” Zawaki said.

Fields said she has “never heard of such a situation,” in her time at Keyspan. But, if it could be determined the gas company was responsible for gas leaks killing trees, “We would work to come to some meeting of the minds,” on how to proceed, she said.

Fox did not respond by press time to Gazette requests for information on how much the DCR has spent trying to re-foliate the Arborway.

With the mature red oaks along the Arborway reaching the end of their 100-year natural urban lifespan, and the DCR’s apparent inability to get replacement trees in, it might be plastic or nothing, according to Handly.

“There will be very little canopy left in very little time,” he said.