Ottawa restoration companies are inundated with calls from households beset by sewage backup from Thursday's flash floods, which caused "catastrophic" damage to some homes. Deven Raval, owner of PuroClean, called it "mayhem." He said his company normally deals with five or so calls per day. But this has been different. "My phone's going crazy," he said, as rings repeatedly interrupted an interview. He'd already fielded about 70 calls as of Friday morning. He said four of every five relate to sewage.