These come in very handy during a power outage: inexpensive to buy and run.
Light It! 30302-308 Luna LED Tap Light, White 30302-308 - The Home Depot
Amazon.com: GearLight Camping Lantern - 2 Portable, LED Battery Powered Lamp Lights, Magnetic Base and Foldable Hook for Emergency Use or Campsites - Stocking Stuffer Gifts for Men : Sports & Outdoors
And for water issues:
Quick Dam 10 ft. Flood Barrier QD610-1 - The Home Depot
The Quick Dam works great and it is very easy to use. And it can be used over and over.