Water puddles have formed within this crawl space and can be a major problem for the homeowner. Water is a clear sign that there is either infiltration from the outside seeping in, or that the relative humidity has reached 100%, in which case the air cannot hold any more water and condensation forms on cooler surfaces in the crawl space. Water puddles left by floods or leaks will also cause the relative humidity to elevate with warmer temperatures, leading to other issues such as mold and mildew, structural damage, and wood rot.