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Protecting At-Risk Cities From Rising Seas
Hugh Pickens writes "BBC reports that with about 10 million people in England and Wales living in flood risk areas, rising sea levels and more storms could mean that parts of at-risk cities will need to be surrendered to protect homes and businesses, and that 'radical thinking' is needed to develop sea defenses that can cope with the future threats. 'If we act now, we can adapt in such a way that will prevent mass disruption and allow coastal communities to continue to prosper,' says Ruth Reed, President of the Royal Institute of British Architects. 'But the key word is "now."' Changing sea levels is not a new phenomenon. In the Netherlands, for example, with 40% of its surface under sea level, water management and water defense have been practiced since time immemorial; creating mounds and dykes, windmills, canals with locks and sluices, the Delta Works and the Afsluitdijk, all to keep the water out. Similar solutions to protect British cities are based on three themes (PDF): moving 'critical infrastructure' and housing to safer ground, allowing the water into parts of the city; building city-wide sea defenses to ensure water does not enter the existing urban area; and extending the existing coastline and building out onto the water (using stilts, floating structures and/or land reclamation)."
In other news, Himalayas have seen a surge of new visitors and people moving in.
Live in a house boat. They float. An chicks dig house boats.
Do anyone has thought that instead of investing resources in fighting rising levels, it may be cheaper and safer constructing in the long run on higher terrain (england has many country parts), New Orleans tried to do the same and look at the social and economic impact it had
Xirvin
the Delta Works and the Afsluitdijk
I've heard of some crazy Scandinavian names, but come on. That's just somebody banging on the keyboard. Next you're going to tell me about the famed Swedish Lkajadsfglkn.
There are two types of people I can't stand:
People who are intolerant of other people's cultures.
And the Dutch.
Even though they are clearly marked on the maps, and (presumably) are discovered in property searches, people still buy these places. Yet when the inevitable happens - for rain is a fact of life in England, they whine and moan about "our house has flooded ... you gotta HELP us!" Better still, a lot of river-side properties are very desirable and attract huge premiums. The buyers seem not to associate having a large body of moving water, passing by the bottom of the gardens to their million-pound houses, with any sort of risk, at all.
All I would suggest is huge .... massive .... crippling ... increases in home insurance premiums to both alert buyers to the dangers and also to make them pay the going rate for repairs and renovations - rather than being subsidised by all the sensible people. Just like happens with car insurance.
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
The US Eastern Seaboard has major problems with beach erosion. The real problem is that sand beaches have never been static; they erode, move, and build up in different spots depending on vagaries of currents and storms.
Of course idiots still want beachfront property as close to the ocean as they can get, so the obvious solution is to have Congress subsidize rebuilding the beaches and paying for flood insurance. If the government would just get out and let the property owners bear the real cost the problem would solve itself.
New Orleans? I'm not convinced it's all that special. Move it inland about 50 miles and the problem goes away
We will earn shitloads of money in the coming decades, building dikes and other stuff for other countries. If I had to choose a study now I would go to Delft, where all the relevant education concerning that is given.
-- Cheers!
3. Go and visit the Thames Barrier. It's very impressive.
What about sewers? Much of London's sewer system is more than 150 years old and will last for at least that long again thanks to good engineering and great foresight by the Victorian planners. If we had to rebuild our sewer system every 90 years, we would be spending a great deal more on our water bills than we do at present.
Thames Barrier? Pah. It's already too low. See this article in The Independent
"Cock Up Your Beaver" does not mean what you think. This sig is intended to clog filters and annoy do-gooders
> If you happen to live in these flood prone locations there are two choices:
> a) Fix the entire world to stop rising waters ---- not likely.
> b) MOVE to higher ground.
You forgot option 'c' --
c) Make the ground you already own a foot or two higher.
A hundred years ago, the land my house sits on (western Pembroke Pines, Florida) was theoretically (if not actually) underwater a few months per year. It wasn't swamp... it was outright, honest-to-god 'Everglades'. Yet, talking to my neighbors, the neighborhood has never flooded -- or even came close to it -- in ~30 years.
Why?
The big dike a few miles west, and the huge drainage canals everywhere obviously help... but there's another factor: the developer turned the low-lying areas into deep lakes, and used the debris to raise the surrounding area. So... when we have a really bad (read: daily) summer downpour, the water runs into the storm drains, then gets dumped a few hundred feet away in those same lakes.
The work quite well. Last month, large parts of South Florida were flooded for a day or two after massive downpours that dumped more than a foot of rain. We barely even had puddles on the roads.
Media propaganda to the contrary, FEMA doesn't just dump money into low-lying areas. If you build a house in a floodplain and it gets flooded, FEMA (as a condition of making flood insurance available to an area) requires that the local government pass laws requiring rebuilt homes to have their lowest habitable floor a couple of feet above the "500 year" water level. You can buy landfill to raise your lot's height, you can build on pilings, or you can take the insurance money and head for the hills. What you *can't* do is put yourself in the exact same situation you were in beforehand.
Over time, economically valuable parts of low-lying cities will get rebuilt on pilings. Over the next 25-50 years, the roads get rebuilt higher, with better storm drains and stormwater retention ponds.
The controversy in New Orleans is that people in the flooded areas wanted special treatment & exemption from the rules -- to which FEMA firmly said, "No. You'll rebuild on pilings, or you won't rebuild. This isn't oppression by The Man... it's common sense."
My prediction: the poorest, lowest-lying, most destroyed parts of New Orleans that aren't likely to be rebuilt anytime soon will sit vacant for a few years, until property values rise high enough for large corporate developers (Toll Brothers, Lennar, etc) to start quietly buying up large tracts of low-lying land. Once they own enough, they'll do the same thing there that they've done in Florida: dig a deep lake and/or surround the new community with a moat^h^h^h^h linear retention pond, build new concrete storm drains and streets above the historical flood level, then backfill the remaining area & turn it into expensive waterfront suburbia.
Want to know what future coastlines in areas supposedly vulnerable to rising sea levels will look like? Go to South Beach. Most people don't even REALIZE it until you point it out to them, but it's actually surrounded by a huge dike -- the artificial dunes built as part of the beach renourishment program in the 80s and 90s, and the streets along the island's perimeter that have been progressively raised during widening and reconstruction to form de-facto dikes. Ditto, for Miami's bayfront neighborhoods.
The strategy is simple: raise the roads, and let the wealthy property owners on the lower waterfront side worry about raising their own property level when they end up rebuilding -- possibly due to storm damage, more likely due to bulldozing away the older single-family homes and replacing them with skyscrapers. Any time a road in Florida gets widened, it almost always gets rebuilt a foot or two higher than it used to be. Stir, rinse, repeat for a hundred years, and by the time the sea level rises enough to flood areas that are dry today, hardly anyone will even notice. The areas that flood will have been floodin