From what I’ve heard, sea levels could rise five or ten feet over the next couple centuries. That’s pretty gradual. Eventually though, a lot of large coastal cites will find themselves flooded. Assuming we don’t build large dykes around our coasts, how will we prepare areas that are eventually going to be abandoned to the sea? There’s a lot of toxic waste in cities I assume.
Or do you think we will build massive dykes all over?
I think humanity has proven that it’s not capable of long term planning. Nothing beyond 25 to 50 years. Look at our inability to capacity plan roadways, tunnels and bridges. Some would argue it’s not cost effective to plan that far into the future and they may be right.
So coastal cities will build inadequate dyke systems which will be overwhelmed by coastal storms. Cities will suffer catastrophic destruction. Thousands may die. Property will be destoyed. Can’t rebuild on water so people will slowly retreat in-land.
It won’t be pretty and certainly very little prep and cleanup will happen to avoid waste poluting the ocean. Also, who’s going to pay to move dumps and sewage processing plants?
I’d like to believe the gradual sea level rise will give plenty of time for people to pack up and move inland. Perhaps the US would give some compensation like they do for other natural disasters?
The OP raises a good point about what will be done with existing buildings. It would be a navigation hazard to have buildings only covered by a foot or two of water. They really should be torn down. I’m not sure if there will be enough time or resources to do that. The smart people will sell out and leave a few years before the rising waters force them out.
There are examples in recent history that can be studied. Like when the dams were built for the TVA in Tennessee. What was done to prep that area?
On the positive side an entirely new group of people will find themselves owning highly coveted and valuable seaside coastal properties. A unique redistribution of wealth. One person’s disaster is anothers good fortune.
North Carolina will be denying ocean level increases when Charlotte is three feet under water. We will do nothing at all.
Boat drivers already know that they can’t go everywhere just because there’s water.
Buildings wouldn’t be much different that reefs.
We don’t have to worry about it. We can just dump some detergent in the ocean to clean it.
The opening scene of the Sci Fi movie *Trancers *features the main character scuba diving over the remains of submerged LA. Quite a vivid way to start a movie. 
Massive dykes…inadequate dykes…large dykes…
Folks, unless we’re talking about the after party of an LPGA tour event, the word you’re looking for is “dikes.” 
Opening shot from the *Trancers *movie. It gets even better when he’s scuba diving there. Thats about what our current coastline will look like in a 150 years.
http://www.blogcdn.com/blog.moviefone.com/media/2010/06/trancers05.jpg
Tide?
We have built cities near the ocean 'cuz we like living near the ocean. The ocean already periodically rinses the streets or blows apart those cities.
We have built cities in earthquake zones 'cuz we like living near earthquake zones. Those earthquake zones already periodically topple those cities significantly.
The idea we’ll plan for the long term, or sacrifice what we feel like doing right now in order to avoid some future catastrophe, is completely unsupported by our behavior to date.
Worrying about the consequence of today’s behavior being visited upon future generations is a luxury anxiety hobby for cocktail parties; not something that should be taken seriously.
I would say it’s a given that little to nothing would be done to clean up land that was about to be flooded.
As a thought experiment, imagine that this fall, a hurricane floods New Orleans again. President Obama, not having to worry about getting re-elected, announces “Fuck It. We’re not rebuilding a city that’s already below sea level. All the flooded parts of New Orleans will be declared a federally-protected wetland.” Cleaning up the toxic soup would take decades, even if they made a serious effort. But they wouldn’t, because resettling the displaced people would eat up all available money, and there wouldn’t be any “deep pockets” company like BP who they stick with the clean-up tab, so they’d just make a token effort for the cameras and call it good.
I’ve been having a lot of fun playing with this site. The melting of the West Antarctic glacier that’s in the news these days is expected to cause a 3-4 meter rise. As I’m from the SF Bay Area, I’ve been thinking about how the area will be affected… SF and Oakland Airports will both be under water. Most of the major ring of freeway around the Bay will be at or under water. Significant wetlands will be really wetlands. Most of Richmond, Emeryville, and the South Bay will be flooding. The San Joaquin Valley will probably be flooding, if we don’t do something fairly massive, like put a dam across the Carquinez Strait, which would probably cause a few shipping problems. Maybe locks would need to be installed…
The Bay Area (and particularly San Francisco) gets drinking water from the Hetch Hetchy reservoir system in the Sierras; the water travels through an open-air aqueduct near Stockton to Hayward, where it is pumped under or around the south bay to a reservoir south of San Francisco. With a 4 meter rise, significant portions of that will be under water; at 10 meters, which would call for major polar melting, the entire system will have to be rerouted around the newly-formed San Joaquin Sea. Or, we’ll need to set up huge solar arrays to power water desalinazation plants, or abandon most of the Bay Area as unlivable due to lack of drinking water.
channel markers are used to indicate safe travel areas already.
I know why it shows that way, but I can’t help but snicker at how every increase in sea level turns Death Valley into a deeper lake.
On the up side, a 2 meter rise will flood Sacramento, so we have that going for us.
Although the rise in sea level will happen over several years, it’s not like the water is going to slowly creep forward a few inches at a time. There will be single devastating events that suddenly wipe out huge areas in a day, like Superstorm Sandy and Hurricane Katrina. Our history has clearly demonstrated that we won’t adequately plan for this, and there not be any planned relocation as long as houses and buildings are still standing. Diceman has it right.
I found my parents house on there, to see how much the sea will have to rise before my inheritance is ruined.
According to that site, their house is already underwater.
I should probably make some calls.
I suppose there will be people who scavenge metal, like there already are now. That’s about the extent of cleaning I’d expect.
Seattleite here. For small rises of only 2-3m, the area is mostly unaffected except for the losses of Renton and Tacoma. I don’t know where all of those car dealerships and strip motels will relocate to.
At the 40 meter level (total polar cap melt-off), the house I was living in in Berkeley was about three blocks from the Bay. So, prime real estate!