Metro restored subway operations to all its Blue Line yesterday afternoon and got through the evening rush hour with only one major delay.

It was the first time since last Thursday night that trains have carried passengers between the Stadium-Armory and Federal Triangle stations. Seven Metro stations had been closed after two were flooded in a construction accident.

Despite the fact that passengers had used buses or cars to get to closed Blue Lin destinations in the morning yesterday, there were substantial evening rush-hour crowds.

People streamed off trains at Stadium-Armory and raced outside to parked buses. "I'm glad to have it back," Shirley Federigon said as she waited to board her bus to Greenbelt. "It was confusing not having it."

Rita Davis, station attendant at Stadium-Armory, said "It's just like a normal rush hour."

Metrobus service had been augmented during the subway problem, but buses reverted to old schedules yesterday afternoon and everybody seemed to understand what was happening.

There was one major delay of about 15 minutes on the Stadium-bound. Blue Line when a balky train was turned around and taken out of service at the McPherson Square station.With that problem resolved, trains began moving normally again.

One other problem cause a two minute delay at Metro Center. There the doors of the rear car of one train refused to open. Usually they refund to close. A train supervisor stepped into the cab and reset a switch to solve that.

Metro officials had originally hoped to restore full subway service Monday. After Metro crews worked through the weekends to clean up traffic and replace silt-filled equipment they were ready to do so.

But the source of the shutdown - water seeping from the Washington Channel through a construction site into the Metro tunnels - was not contained until late Tuesday. Concrete plugs were poured in two Metro tunnels Tuesday night and service was restored yesterday after the plugs had hardened.