To say nothing of the launchpad sound suppression water system[1] that dumps 7,300 gal/sec (about 2–3 seconds for one swimming pool)!
Though that's just gravity-fed, of course. Still pretty cool though, I think (:
[1] https://en.wikipedia.org/wiki/Sound_suppression_system
The article uses various measures, so here's a quick table:
Baikonur Cosmodrome: 4,800 gal/s (peak) Space Shuttle Launch Complex 39: 7,317 gal/s (net) Wallops: 4,000 gal/s (?) SLS: 18,333 gal/s (peak) Mack Super Pumper (this article): 146 gal/s (net) Replacement new Super Pumper 1: 87.5 gal/s (net)
The article uses various measures, so here's a quick table: