I don't think the recovery costs would differ much though.. flooding causes damage to wood/flooring and mold, dirty or not.. What you end up doing here is screw yourself out of an insurance claim. Insurance has no obligation to cover intentional flooding and you could even be charged with insurance fraud. As obsurd or unbelievable/unrealistic as it may seem, insurance could claim that the damage may not have been incurred if it wasn't for the intentional act. The company is going to look for any reason to deny your claim whether your intentions were good or not. Unless you can absolutely prevent any/all damage.. Just let mother nature do her thing and hope for the best.