Flood zone

What is the name of your state? AZ
I purchesed a plot of land in Arizona and had a house built on it.
Before I purcxhased the land I did the research on flood control.
Maricopa County states my lot is coded zone X,which means it is outside the 100 year flood plain.
Since I built me home, Maricopa county is reassesing the flood planes in my area.
This past Saturday there was a flash-flood that exited the nearby wash and flowed directly into my property. Although the water did not enter my home it surrounded my house and in some areas was 10" deep.
Do I have any recourse with the county as the information they gave me was the determining factor in purchasing this property?
Thank you

no

doesnt really sound like you have a problem. Your house didnt flood, but you say you have a wash that runs ten feet deep. I live in an area (in AZ) that drains 12 square miles and the wash only runs 4-6 feet deep. so the nearest watercourse is normally dry and run TEN FEET DEEP during a storm? are you sure about that?, how far away from your house is this wash? How many feet abouve the bottom of the house is the finish floor of your house?

The water surrounded my house and in places was 10 inches deep. There is no wash at present, but from older aerial photos It appears that there used to be one but was graded over when the dirt road was put in. My finish floor was about 18 inched above the water line. My concern is this was not a major rain such as we had in spring of '05. I am obviously in a flood plane but the county states that I am not. I would like to get the county to improve the drainage as they were the ones stating there are no flood issues here.

No, the county did nothing wrong. In doing your "research" are you saying that the ONLY source of information was the county? You didn't do much research, then. Also, your lender (if you have one) would have required flood insurance as a condition of the loan if you were in a high risk area.

everywhere in Arizona floods when it rains. You could be in downtown Phoenix and have 8-10 inches of water outside your door. Buy additional flood insurance. Just because you are not in a flood plain and REQUIRED to buy it, doesn't mean that you can't.

I think you misunderstand "flood plain"

water runs in water courses, there is a bottom of the course, the estimate of the depth of water plus the ground level determine what is "flood plain", the water did drain out after the rain stopped? right, then you just have normal runnoff. Pluss your not supposed to grade over watercourses. See the army corp of engineers, it take a special section 404 permit to work in a water course(dry or not). You cannot discharge dredge or fill in a water course dry or not. Do some dirt moving and you can probably correct any little problems you have.