By Marcy Stamper
Winthrop, Mazama and Twisp River customers of the Okanogan County Electric Co-op (OCEC) should be powered by a redundant backup connection in the spring, after transmission-line feeds at the Twisp substation are switched.
In one of the final stages of the Okanogan County Public Utility District’s (PUD’s) Pateros-Twisp transmission line, the connection in Twisp from the existing Loup Loup line will be transferred to the new transmission line that comes up from Pateros, said David Gottula, OCEC’s general manager.
The connection was expected to be swapped this past fall, but was delayed because the Bonneville Power Administration (BPA) is still working on a required environmental review, said Gottula.
The new 27-mile transmission line was energized from Pateros to Twisp in October 2017, providing a redundant system for PUD customers so that power can come from either Pateros or over the Loup during an outage or maintenance. Some 10 to 15 percent of OCEC’s customers near Twisp are already served by the new line, said Gottula.
The changeover will most likely be scheduled in April and will necessitate an 11-hour outage, probably overnight, said Gottula. Once the wiring has been reconfigured, there will be another shorter outage to finish the work. After that is complete, all of OCEC’s customers will have two true sources of power that can be switched between the Pateros-Twisp line and the Loup Loup line as needed.
Rerouting the transmission line should cost $175,000, according to the PUD’s budget for next year. The PUD and BPA have signed an agreement to move forward with the work.
“There are always delays on transmission and substation projects,” said Gottula. “I wasn’t all that surprised.” Gottula said cooperation from all the partner utilities had been excellent.
Load increases in Mazama
The electric co-op is continuing an upgrade to increase the voltage carried by the distribution line that serves Mazama. While the line is still adequate, the increased voltage will help handle peak loads, primarily on very cold winter weekends when vacation homes and tourist cabins are occupied, said Gottula. More work on the half-million-dollar upgrade is scheduled for this year and should be completed in 2022.
The co-op continuously monitors the demand on its infrastructure. The additional load over the pre-Christmas holiday weekend was so small that it didn’t even register, said Gottula.
The multi-year project is intended to accommodate potential new construction over the next 10 to 15 years, said Gottula. The section that’s yet to be completed runs from the Weeman Bridge to Lost River.