Wednesday’s power loss was due damage from a fallen tree near Hesperus on the region’s main 115 kV line. San Miguel Power Association then tried to re-power the region through its aged 69 kV transmission line from the Nucla power plant, but the load was too great, blowing a jumper at the Norwood substation.
The Tri-State Generation and Transmission Association, the region’s wholesale supplier of power, in 1998 proposed upgrading the 69 kV line to a modern 115 kV line, but that application has been stalled due to a long controversy over whether Tri-State must underground portions of it.
“The damaged 115 kV transmission line is what feeds Telluride,” said SMPA Manager of Public Relations Bill Green. “This line comes in from the south, goes through Silverton and up and over Ophir pass. We tried to fix the load by pulling it up from Nucla. When we picked up the load, we burned a jumper outside the Norwood Substation.”
At one point Wednesday afternoon, Tri-State crews were on site to fix the damaged 115 kV line in Hesperus, while SMPA crews were on site fixing the blown jumper in Norwood. Both crews finished at about the same time. Had the planned 115 kV Nucla-to-Telluride upgrade been completed, the upgraded line “would have handled the load without any problems,” according to Green.
The real risk to the region, SMPA and Tri-State have repeatedly warned, is that an outage on the Hesperus line during the winter might be impossible to repair until the spring, leaving the Telluride region without a reliable backup. In that light, this week’s four-hour outage could be considered only a minor inconvenience.
Indeed, in March 2004, an avalanche near Ophir took out the Hesperus line and there was considerable doubt whether or not it could be repaired promptly due to continuing risk of further slides. As it happened, the avalanche site was relatively accessible to repair crews and power was out for only a few days.
Over the past 10 years, the San Miguel County Commissioners, Tri-State officials, various land owners, and the Colorado Public Utilities Commission have disputed the various aspects of the proposed transmission line upgrade that would meet the Telluride region’s need for backup source of power when the main line lines is out.
The commissioners have sided with the landowners who live on scenic mesas west of Telluride, who wish to have the upgraded line constructed underground at Tri-State’s expense. The parties have disputed not only whether Tri-State or the affected landowners should pay for the difference in cost between an underground and overhead line, but also how to calculate that difference. The matter remains tied up in litigation.
“For nine years this thing has had its ups and downs mostly in the courts and that is where it is still standing,” said Tri-State public relations manager Jim Van Someren.
“I think our intent is to get everything wrapped up in court before we begin construction.”
In a he-said, she-said dispute over the cost of the relative costs of an overhead and underground line, the Colorado Supreme Court ruled on April 30 that the court “does not generally require the PUC to include advisory memoranda in the records of PUC decisions and orders. However, [PUC] staff injects new factual information into the proceedings…and this factual information has not otherwise been made part of the record, the PUC must include such factual information…”
The Supreme Court’s decision sets the stage for the San Miguel County District Court to proceed with the case. Meanwhile, the region’s primary transmission line – which traverses Ophir Pass and is the highest transmission line in the United States and vulnerable to all manner of geohazards – is itself aging and the Nucla line just this week proved its incapacity. Indeed, SMPA officials have repeatedly warned that the Nucla line is so old that it will inevitably fail, sooner or later. Rolling brownouts or prolonged power outages could become increasing familiar to Telluride and the surrounding region.
“All of these things are related and all are interconnected and right now, we don’t have too many options,” Van Someren said.