Purchased a house a year ago and am now realizing that the sellers did not disclose that basement leaks. Any legal recourse?

Probably not unless you could prove they deliberately concealed the problem from you. The disclosure laws make it tough as you likely signed documents saying you knew it was up to you to check it out as much as you wanted. Have a local real estate lawyer look at your contract to be sure but you're probably better of spending your money on repairs as opposed to litigation.