. >> reporter: dereck glascoe says he felt helpless stopping the water coming into his apartment. >> i started putting down towels and realized it wasn't going to stop anything. then i started putting things on top of my bed. by the time, i saw the water was seeping through the walls and it overtook the whole house after that. >> reporter: it will likely take weeks to dry out and repair. san jose officials say the cause of the flood is under investigation but appears to be a case of debris flow including logs that jammed up the narrow creek causing it to change course and flow into the apartments. >> it's still the case that things can happen during prolonged winter storms. you can have trees fall into the waterway, other debris get captured. small mud slide and very quickly have the creek over top the bank. we can't always prevent that. we do our very best. i think we can prolong. >> for now, derek and his two daughters who live here are trying to count their losses and save as much as they can. >> i haven't heard anything about how long or what their plans are to fix it. i'm sure t