A water main break on Oak Bay Road near Port Hadlock on Nov. 27 and downed power lines on Thorndyke Road north of Coyle on Nov. 30 capped off a month that Jefferson County Public Utility District described as prone to “widespread outages.”

PUD Communications Manager Will O’Donnell said the water main left three dozen people without water for about four hours but was repaired by 5 p.m.

“It affected 45 homes along Oak Bay Road between Cleveland Street and Eagle Ridge,” O’Donnell said. “The cause was a rusted 30-year-old connector on the main water line that broke.”

The Thorndyke Road outage Nov. 30 left 55 customers without power and was caused by a car that hit a tree. In turn, three power lines that serve the area were taken down, O’Donnell said.

He said one of the PUD’s widespread outages during November was due to extreme weather.

“The largest outages were eerily similar in cause and scale,” O’Donnell said.

The first occurred Nov. 2 and affected more than 16,000 customers for four hours. A second, on Nov. 21, affected more than 13,000 customers for two hours.

The PUD has more than 19,000 electrical customers in total, O’Donnell said.

“Both outages began around 10 a.m., and both were caused by trees falling onto transmission lines,” O’Donnell said. “Trees falling onto power lines are the most common cause of outages in Jefferson County, but most outages involve distribution lines, which lead to homes and businesses.”

O’Donnell identified both outages in November as occurring when “tall, skinny fir trees” fell onto transmission lines between the Bonneville Power Administration’s substation in Discovery Bay — where power is received from the lines originating at dams on the Columbia River — and secondary substations in Port Townsend.

Although power could not be restored during the first widespread outage until the tree was located and removed, the PUD isolated the section of line affected by the tree during the second widespread outage. O’Donnell said that allowed the PUD to restore power to the Chimacum and Port Ludlow substations before the tree was fully removed.

Despite occurring twice last month, PUD officials deemed large-scale transmission outages rare. PUD Resource Manager Bill Graham’s research indicated the most recent previous widespread outage occurred in December 2015.

“They’re rare because the corridors that transmission lines run through have wider clearances than those adjoining distribution lines,” Graham said.

Graham dismissed any possibility the trees that caused the November outages would have been affected by PUD’s normal trimming schedules.

“They were tall and spindly, and crews suspect that freshly loosened soils and weak root structure led to their fall as much as the wind,” Graham said.

PUD General Manager Larry Dunbar has asked staff to re-inspect the transmission corridor for more potential tree problems as soon as possible, describing the prevention of large-scale outages as a “top priority.”

O’Donnell said preventing outages such as those that occurred during the 50-plus-mph gusts Nov. 26 would be “more difficult,” given that power poles and distribution lines were knocked down in multiple locations across the county, while trees fell and limbs littered roadways.

“A semi was entangled in BPA power lines on Highway 104,” O’Donnell said. “Outages were reported from Gardiner to Coyle, and lights flickered across the system. No more than 1,600 customers lost power at one time, though some did for almost 15 hours, when two poles came down on Center Road.”