Some Petersburg residents went without power during two, long outages on Saturday. Both black outs were caused by an insulator problem in the Scow Bay area and affected the core area of Petersburg including downtown.
The first outage started at about 10:30 a.m. and lasted an hour and a half. The second one happened just after 2 p.m. and lasted nearly two and a half hours.
In a press release, Petersburg Municipal Power and Light Utility Director Karl Hagerman said the crew first found that the Blind Slough hydroelectric plant had tripped off but the circuit that serves Mitkof Highway was still working. They patrolled the line to look for damages but didn’t find any. They put the Scow Bay generator online and power was fully restored at noon.
Initially, the utility thought that the problem was something momentary like a bird strike. However, just after 2 p.m. a second outage occurred on the same circuit. It was reported by Scow Bay customers after a loud noise and sparks were witnessed in the area. Some equipment had been damaged–a porcelain insulator on a pole in the Scow Bay turnaround area. The line crew replaced the damaged insulator plus two more on the pole with polymer resin based ones to prevent future problems. Hagerman said older, porcelain insulators can crack over time, allowing water to seep in, which can lead to more degradation.
After repairs at Scow Bay, the power was fully restored to Petersburg customers by about 4:30 p.m.
The supply of hydroelectric power to the region through Southeast Alaska Power Agency (SEAPA) was not affected. SEAPA provides hydroelectricity to Petersburg, Wrangell and Ketchikan.