Amtrak plans to renovate Penn Station’s notoriously disgusting bathrooms by the end of the year — but to do so, it will have to bring in portable toilets, officials said Friday.

Amtrak officials have not yet decided whether to start with refurbishing the men’s rooms or the women’s rooms.

But either way, the men’s rooms will be shut down all at once — forcing the portable toilets on male travelers for the duration — and the women’s rooms when it’s their turn.

Amtrak has been doing major repairs on Penn Station ever since a series of derailments and other incidents caused chaos the hub last spring.

The company finished a major renovation of some of its aging tracks last week. It still has to replace its signal and electrical systems.