1. Clear Storm Drains. If you have any storm drains on or near your property, make sure that they are nice and clear of any debris such as leaves or twigs or rocks. This is your first line of defense against rising water, so you want to do all you can to help it do its job. If you know a large storm is coming, walk around and make sure that all of these are clean so the water can be funneled out from your area.
2. Keep A List. Tell your residents to keep a list of anything important and the price these things cost. This will help in the event of an insurance claim. You should keep a list of everyone living in your rental property and their phone numbers so that you can get a hold of them and make sure they are okay as well.
3. Keep Supplies. Both you and your residents should keep certain supplies in case the flooding gets severe. This should include drinking water, non-perishable food, flashlights, and a battery powered radio. You should also make sure to have a first aid kit on hand just in case someone does get hurt.
4. Gutters and Ditches. If you can, make sure that the gutters are clean before a storm. This will help to prevent localized flooding and leaks. Also, some people dig small ditches where they know it floods in an attempt to drain the water back into the ground and away from the building.
Flooding is never a fun thing to have to deal with. It can be rather frightening and can change your life if severe enough. With these tips, though, you may just be able to help lessen any damage that may be done by the onslaught of water from the sky. Remember to keep an eye on the weather so these things don't take you by surprise!