Ah, the hazards of poking around someone elses home. We do get a fair amount of rain during the winter months in western Oregon. All of that precipitation can sometimes lead to a high water table. That is one reason there are so many crawlspaces in this area. If water does come up out of the ground it is hopefully safely covered with a nice plastic vapor retarder, instead of wreaking havoc with finished surfaces.
It can be very common for inspectors to see standing water when it comes time to crawl around with the spiders. I am not afraid of water, however when water is present with electricity that is a different story.

 

I came upon this deadly little coiled booby trap the other day.

 

This wonder piece of homeowner electrical handiness was currently energized, thank goodness the crawlspace was dry.