Springs rains, floods, and groundwater can accumulate in the basement. It’s a good idea to take a close look in all of the nooks and crannies in the basement including the overhead to make sure there are no leaks that may lead to mold growth. Spring reveals mold in basements and attics that may have gone unnoticed through the winter months.
Building Science Corporation is a good resource for property owners trying to solve mold and water problems. Their Understanding Basements post is very informative and highlights some common deficiencies as well as offering solutions for them. buildingscience.com has a number of posts on all aspects of building under its Popular Topics, Homeowner Resources, tab.