Another power outage in SLO County…the third in a week. Last week, several thousand customers in Arroyo Grande and Pismo beach lost power. Last Monday morning, several thousand in SLO lost power. And last night, several thousand in Arroyo Grande lost power. The outage was caused by a damaged underground cable. Five Cities Fire says there were reports of smoke and flames coming from underground and in front of the 5- Cities Swim Club. They say an underground transformer was involved but the cause of the outage is still not known.