In insurance, flooding is defined as water that emanates from the ground and penetrates your building. Flooding is not covered under a home insurance policy. This means groundwater that floods your basement, water from a broken water main, or any other water that gets into your house from the ground is not covered. Conversely, damage that results from burst plumbing, water from above (rain gets behind your siding) or from within your home itself (overflowing bathtub) is not considered a flood; these situations are often (at least in part) covered under an HO3 home policy.
Flood insurance is available from FEMA, and is resold by many companies under their own brand name. Flood insurance pricing varies by the type of flood zone your property is in, but does not vary by company.
If you are in a flood zone rated B, C, or X by FEMA, you are considered to be in a preferred flood zone and qualify for very favorable rates:
The deductible in a preferred flood zone is $1000 for the building and $1000 for contents.
If you are in a flood zone rated A or V by FEMA, you will pay a much higher price specific to the exact zone and type of construction of your home with respect to the land around it. Prices can range from $400 to $3000 depending on specifics.
The maximum amount of flood coverage available through FEMA on a standard flood policy is $250,000 for the house and $100,000 for contents. Excess flood coverage is not regulated by FEMA, and is available at prices set by individual companies if you require or want more coverage.