https://www.siliconvalley.com/2023/01/13/dont-learn-the-hard-way-flooding-can-occur-anywhere/

Q: With all the heavy rain, our backyard flooded. So now our crawl space has standing water, with the crawl space vents just above the backyard patio. Our backyard is flat until there’s a 45-degree incline that reaches our neighbor’s property. Bummer for us, it never dawned on us to buy flood insurance. 

We purchased the home during the summer, and we’ve since reviewed the home seller disclosures. There’s no mention of ponding water or rainwater runoff issues from the properties above us. But now there’s a bunch of storms coming our way, and we’re midway through the rainy season. We called the remediation companies, but they can’t accommodate us now, so tomorrow my father-in-law will set up a sump pump in the crawl space. Making matters harder, we’re worrying about mold in the crawl space from all the flooding.