There are three reasons why you may have moisture in your crawl space. First and foremost, surface water can make its way in. Depending on where your crawl space is located, this can be because of roof drainage, grading issues, overflowing gutters, leaky window wells, or leaky basement windows. Groundwater is also a potential culprit. When the soil around the foundation has been exposed to periods of heavy rain or snow, the soil will eventually push that moisture through the walls of the foundation and into your crawl space. You might also have plumbing issues like a burst pipe or another kind of leak that is causing damage. It’s important to have a professional check of either of these three things so they can properly assess and fix the issue.