HOLYOKE, Mass. — The operator of the region’s power grid declared a power watch for Maine today and asked residents to cut back on their electricity use.

Power plant and transmission line problems in the state have lowered the system’s capacity, and ISO New England officials called on residents to turn off unnecessary lights and appliances and postpone activities such as laundry and dishwashing.

The grid operator issues a watch as a precautionary step before it declares a warning, a more urgent plea issued when electricity supplies are stretched extremely thin.

The watch is expected to last until tonight, a spokeswoman said.