Avista Utilities is nearing the final rung of its transmission line and pole replacements around Moscow this year stretching seven miles south to Thorn Creek Road.
The energy company planned to install fiber optic cables and replace wood poles with steel ones across Paradise Path from Berman Creekside Park to connect to its 230 kilovolt substation Thursday, but was unable to process a request to de-energize the current lines until Monday. That portion of path is expected to be closed all next week.
"Much of it will help capacity, reliability and just safety as well," said Paul Kimmell, regional business manager for Avista. "This happens to be a $200,000 fiber (optic) replacement project. A lot of this didn't have fiber before."
It represents a small portion of the $7.5-million, three-phase project to replace 90 poles and conductors in the Moscow area.
Kimmell said transmission rebuilds are replacing lines 70 to 80 years old and includes switching out copper conductors for larger aluminum ones with 4 1/2 times the transmission capacity.
"We have definitely gotten a good life out of them," he said. "Going to steel improves the integrity of the overall system."
While fiber optic cables can run underground, Kimmell said it is more costly and difficult to maintain the lines that way.
"Transmission is such a larger system that it's just difficult and very expensive to do," he said. "It's just preferred that we continue to put it above ground."
The new transmission lines will tie the city substation by Pets are People Too along the Troy Highway to the 230 kilovolt substation across from the Elks Lodge Golf Course, which serves the entire Pullman-Moscow area.
Avista is two years into a 5-year project to rebuild the 230 kilovolt substation as some of its equipment is nearly 50 years old, Kimmell said.
The cost of the project is estimated at more than $5 million and includes new gas circuit breakers, a 250 megavolt ampere autotransformer, two 115 kilovolt capacitor banks and two 115 kilovolt capacitor banks. The autotransformer was shipped in by rail and truck in December to the new facility location alongside the current substation.
"As the new (substation) gets complete, then we'll demolish the old footprint to the west," Kimmell said. "The current capacity, we were kind of at our limit. It's not only population growth, but it's just customer load. People have more demands per capita. We have just more things plugged into the wall than 20 years ago."
The new facility is anticipated to communicate better with the Moscow city substation, he said, identifying issues within the system and taking steps to repair them automatically.
"Ideally the improved reliability reduces our cost," Kimmell said, "The communication that these two substations can talk to each other and self-heal."
The next two phases of transmission line replacements are slated for next year and 2014, and will continue south to Avista's substation on Down River Road north of Lewiston.
Brandon Macz can be reached at (208) 882-5561, ext. 238, or by email to bmacz@dnews.com.
