We'd say the sewers are generally about the same level of SNAFU as the streets. They don't seem especially impacted... at least the levels the Shuten and Tamamo have been fighting within.

Remarkably... the energy doesn't seem to reach the lowest levels of the Underground, which should seem odd, right? Because the containment center was on B8 of the tower, so shouldn't the lowest levels be heavily infected?

But they're not. And that's weird. Unfortunately, those doors are just as sealed as they were before, so physical investigations can't be made, but if Bishop looked down there, he definitely would notice this.