Generally speaking most St. Helens homes are in the clear. It is notable that the "in-town" areas of St. Helens are well known to be home to a significant layer of rock. I have been advised it is specifically of the blue basalt-type, extremely dense and some of the hardest rock there is in the world! So it goes without saying that because it doesn't absorb anything, flooding can and has occured in lower isolated areas. Currently, the city of St. Helens is actively working to upgrade the sewer system, in part to help avoid these problems in the future.
The best maps in existence are the FEMA Flood Plane maps and I am sure you can find thos eonline if you just research it! St Helens is mostly out and way above flood with the exception of Riverfront.
I work that area....we just showed there on Weds. Would you like us to help you and than we can run these down for you?
How about some targeted searches being sent to you guys??
Let me know. Great Question as well!
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