If you were looking to buy a house in a coastal area

[Laura Corin]

At what elevation would you want to be? I'm still not sure how much I think the sea will rise in the next fifty years (and this post is not designed to start that debate), but other people's expectations are just as important as the reality in the value of the house.

 

I came across an internationally-achieved figure of 50cms sea rise by year 2100.

 

http://www.howstuffworks.com/question473.htm

 

I also found a scholarly mention of erosion in sandy areas as being larger by two magnitudes than the sea level rise.

 

http://www.cababstractsplus.org/google/abstract.asp?AcNo=20043086639

 

I was thinking that we need to be at least five to ten metres elevated and at least 500 metres inland to escape future buyers' fears. But actually, I'm inclined to make it more like several kilometres inland and a lot higher up. What do you think?

 

Laura

[Melissa in Australia]

I don't know. I live about 1/2 a km from the sea, and about 21m above the sea. there is an estuary between our house and the sea. I have often wondered if the sea rising would put extra weight on the plates, and maybe make them shift?? raising some areas etc..don't know.

[Gwen in VA]

I think it depends a LOT on the local geography.

 

I grew up on the coast in Massachusetts. The coast was ALL rocks -- no erosion problems there! :) But the "normal" tides ran five feet or more, and so storm surges could run a LOT more than that. Nobody (and I mean nobody) built within a few feet of high tide.

 

We now live in Tidewater Virginia, where "normal" tides run only a foot or two. When we kayak, we fequently pass by houses that (in my New England eyes) look like they are built at sea level -- because I am used to houses being significantly higher. But to my amazement these houses do NOT flood regularly!

 

Even if global warming does happen, and even if the sea does rise by 50 cm, most houses would not be immediately affected by the 50 cm -- it's the storms that would cause the damage.

 

Questions I would think about --

 

What direction do the storms come from? How protected is that direction?

 

What is the normal tide run? How high are typical storm surges?

 

What is the land like (silt, rock, sand)?

 

What erosion issues does the area have?

[Kathy in MD]

In addition to Gwen's suggestion, is the land subsiding or rising? Scandanavia is still rebounding from losing the massive weight of glaciers. Islands and shorelines in the Cheasapeake are sinking, supposedly do to the land further north rebounding from past glaciation.

 

Also weather is affected by the proximity to the ocean. If you live near a cold ocean current, fogs are a major problem. The further inland residents typically get more sunshine. Also elevation plays a role here. In parts of CA, you can chose a very high house and look down on the fog, choose one at a low elevation and look up at the fog. Or you can buy one that's just "right" and live in the cold, wet, yucky fog full time.

[greenwillow]

Also, another IMPORTANT consideration - be sure to check with your homeowner's insurance company before signing a contract.....my family lives down where Ivan hit, and the insurance companies will not even provide insurance for home purchases south of a certain geographical cutoff point. Even north of the cutoff, premiums are extremely elevated up to yet another geographic boundary. This may or may not be an issue where you are looking, but better to be safe than sorry!

[Laura Corin]

The area we are looking at is actually sunnier at the coast than inland - it is in the rain shadow of mountains. That's one of the reasons for looking at the coast. There has been serious erosion about 30 miles down the coast - I don't know if the geology is the same, but DH and I have decided that it might affect house values whether it is or not. We'll be looking a few km inland.

 

Laura