Not quite, they are not open to the public. They operate as the local clearing houses for currency, check data and electronic transfers. Yes, it gets reported to the San Fran District Headquarters.
The Seattle branch, at the time anon worked there, had between 70 and 125 million in bills in the vaults on average. Depending on the time of year.
Gold Bullion was also in the vaults, management at the FED wouldn't say how much, though.
The FED has been destroying all bills larger than $100.00 since the mid 80s. The money sorters have a shredder installed.
The $100,000 bills used for inter FED transactions haven't been in use for even longer than that, before my time working there.