So I just went to Necropolis to get the water chip and everyone is already dead. Can I still get the water chip?

Yes. Just get it like ya normally would i.e. go to the vault. Also, I assume ya can fix the water pump to get experiences?

I fixed the pump. What vault are you talking about?

In the room where ya fix the pump, check the jail cell on the south part of the room. One of the jail cell have a manhole that lead ya to the Vault.

Got the chip. Thanks.

The Death Necropolis is something thats triggered after a certain time period.