The crawlspace under our house has a tendency to get a bit muddy when the rains are heavy and then dry up a few days later. When the rains are especially hard water will collect in a pit in the crawlspace and I have to go in with a wet vac to clear out the puddle that has formed.
I've had this explained to me by a contractor as the high water table which comes and goes with the tide (I live in Berkeley, CA) and not something to worry about. Other contractors are pointed it out as a concern. Our neighbors have a sump pump to keep their basement dry.
How do I know if I need a sump pump? What are the risks of not getting one right away? How hard is it to install myself? The house is 100 years old, I assume it's been standing this whole time without one.