The City of Carnation has information about where the flood zones are on their website, http://www.Carnationwa.gov to help you see what is in the flood area and what is not.
Areas marked in blue are in the 100 year flood plain. The map shows that quite a bit of downtown Carnation is outside the 100 year flood plain. As Christine mentioned, much of unincorporated Carnation is up the hill. Our team has raised two families in Carnation and wouldn't have it any other way. Moved up from Lake Oswego, OR 19 years ago!
Wishing you all the best.
Sue, Chris and Tracy
In addition to being a Realtor, I am a Snoqualmie Valley resident. Carnation has some great neighborhoods where you would not have to worry about flooding. Lake Marcel and Lake Joy are a couple of them. There are some good buys in both currently (of course the lake front properties are pricier and not as abundant) but there was one bank owned in Lake Marcel which recently closed for just over $200K). These communities are just as close to Duvall as they are to Carantion. If you are interested in something within walking distance of town, there are some nice subdivisions such as Swiftwater where you shouldn't have to worry about flooding either. Carnation and Duvall both are within the eligibility guidelines where the USDA rural housing loan may be a financing option if you need it. Location, income and family size (as well as not owning another home within 100 miles) are factors which come into play as to whether it could be utilized but it is a great program (better than FHA).
Anyway, if you aren't already working with a Realtor, I'd be glad to be of service!