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Swept away: $500k sand dune built to protect US homes disappears in days

theguardian.com

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Re: Swept away: $500k sand dune built to protect US homes disappears in days

#71

Post by seszett »

LunaSea wrote: post #70
seszett wrote: post #48

Earlier quoted context omitted.

I don't know, in my place (the West coast of France) it's the government's job to protect citizens property. There used to be a dike built in 1856 but it eroded away and in the 90s when I was young the broken sections were replaced with just big rocks[0]. It works quite fine, I believe they wouldn't count as a "hard structure" which is forbidden in this case, and they don't wash away like sand. Beaches form, naturall…

Because they built houses in place they shouldn't have

Were they illegally built without a permit? Then they should be demolished. Were they built with a permit? Then either it wasn't obvious they shouldn't have been built (and then why would the homeowners be responsible for these kind of works?) or there was corruption (and then the relevant persons should be condemned). But privately built seawalls to protect the coast? That seems out of proportion, and unlikely to produce positive results on the long term.

In the same area I'm talking about, people died in flooding during cyclone Xynthia, in 2010. It wasn't because of a particular weakness in the seawall, it was found that these homes should never have been built in the first place.

But they had been built legally, with permits obtained from the town, so 700 of these homes were bought (by the state, not sure exactly which levels the funds came from but France is a unitary state so it doesn't matter much) and demolished. And the mayor who granted the obviously bogus permits was sentenced to prison for the 29 deaths he caused.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#72

Post by scott00 »

I was curious on some of the details, so I did a little digging.

The town in question (Salisbury, MA) is built on a narrow strip of land between a marsh and the ocean. Mostly between 2 and 5 houses wide. Doesn't seem like you need a geology PhD to determine you're going to have some erosion problems here.

As best I could determine, the beach replenishment in question was from access points 5 - 11, which covers 1.6 miles and about 150 homes. If I'm right on that, they put down enough sand to extend the beach 3-7 feet[0]. So the first thing to note is that this was a very small beach replenishment project. The senator is probably right that they should go bigger next time.

The cost per home for that would have come out to about $3333.33. Honestly, even if you triple it and do it every year, I don't find that to be an unreasonable expense to impose on owners of $1-5 million houses built on a sand dune. These guys need to quit whining and raise their _local_ taxes the relatively modest amount necessary to preserve their town. Something like $5k/year for beachfront and $1k/year for the rest would get the job done.

[0] This is assuming a constant slope to the beach. The low end is extending at 3 feet above sea level, the high end is extending at 6 feet above sea level.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#73

Post by kerkeslager »

blagie wrote: post #15
master_crab wrote: post #2

Perfectly acceptable for homeowners to spend their own money to save their houses. But it’s the last sentence in the story that makes me boil over: “Now, the homeowners have asked the state to step in and provide assistance.”

Things which make sense to me: 1. Deregulate / reregulate to where residents are allowed to build a seawall instead of sacrificial dunes. 2. Bring in the Army Corp of Engineers to help with design, planning, and evaluation. Things which don't make sense to me: 1. Blocking people from doing the work. 2. Funding the actual construction with state or federal dollars. This is not an isolated problem. The Army Corp of Eng…

I don't think the Army Corp of Engineers should be wasting taxpayer dollars on this either. Zero federal taxpayer dollars of any kind should be going to building in the way of the ocean just so people can have a beach view.

If people are actually living in the at-risk properties as their primary residence, I'd support spending taxpayer dollars to help them move.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#74

Post by blagie »

detourdog wrote: post #43
blagie wrote: post #15

Earlier quoted context omitted.

Things which make sense to me: 1. Deregulate / reregulate to where residents are allowed to build a seawall instead of sacrificial dunes. 2. Bring in the Army Corp of Engineers to help with design, planning, and evaluation. Things which don't make sense to me: 1. Blocking people from doing the work. 2. Funding the actual construction with state or federal dollars. This is not an isolated problem. The Army Corp of Eng…

The problem with diverting water is that it goes somewhere else. The issue is that Salisbury is in the way of the ocean. Trying to build your way out of that is not going to work. They could establish an annual sand budget and treat it just like snow removal.

I'm not sure water needs to be diverted, per se. The problem isn't baseline water level but waves, and especially large waves, and sand washing away. It seems like the solutions would involve some combination of:

* Breakwaters, to equalize the water levels and reduce the waves

* A few meters inland, some kind of wall (firmer than sand) which doesn't wash away, so a bigger wave doesn't impact homes

* Perhaps some kind of reinforcement underneath the sand

It might reduce littoral drift a little bit, but as I understand, this would be done the length of a rather long coastline, so that's not really an issue.

I have very mixed feelings about just dumping tons of sand into the ocean each year. That's going to have its own impacts.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#75

Post by sp332 »

tromp wrote: post #10

> Local news outlet Fox59 reported that the Republican state senator Bruce Tarr was working to secure $1.5m in state funding to replenish the sand. > Tarr, noting that a more permanent seawall was not an option because hard structures like these are not allowed on Massachusetts beaches If the only alternative is to drain state funds dumping tonnes of sand that quickly get swept away, then it's time to change the (by)…

The houses are getting swept out to sea. The pace may have increased in recent years but this has been a fact of life on the sandy beaches of MA for centuries.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#76

Post by sp332 »

seszett wrote: post #71
LunaSea wrote: post #70

Earlier quoted context omitted.

Because they built houses in place they shouldn't have

Were they illegally built without a permit? Then they should be demolished. Were they built with a permit? Then either it wasn't obvious they shouldn't have been built (and then why would the homeowners be responsible for these kind of works?) or there was corruption (and then the relevant persons should be condemned). But privately built seawalls to protect the coast? That seems out of proportion, and unlikely to pr…

The houses were built 100 years ago, when the ocean was hundreds of feet further away. If you asked the builders, I'm sure they would have told you that this would happen in a century or so. Erosion of sandy beaches isn't a surprise.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#77

Post by sp332 »

scott00 wrote: post #72

I was curious on some of the details, so I did a little digging. The town in question (Salisbury, MA) is built on a narrow strip of land between a marsh and the ocean. Mostly between 2 and 5 houses wide. Doesn't seem like you need a geology PhD to determine you're going to have some erosion problems here. As best I could determine, the beach replenishment in question was from access points 5 - 11, which covers 1.6 mi…

I don't have evidence for this, but my suspicion is that the sand was not supposed to be long-term, but just to look impressive for suckers while the owners dump their now worthless real estate.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#78

Post by Veliladon »

awestley wrote: post #8
master_crab wrote: post #2

Perfectly acceptable for homeowners to spend their own money to save their houses. But it’s the last sentence in the story that makes me boil over: “Now, the homeowners have asked the state to step in and provide assistance.”

I agree, but to be fair it was also the state that limited them such a silly option. They can't do anything more permanent than sand. Which, I understand has an environmental impact, but the beaches are going to keep eroding so why not "draw a line in the sand" so to speak and help protect the beaches more permanently. Regardless of how lives there now. * I live in the state but no where near the water. So I'm sure m…

The beaches keep eroding because the dune ecosystem that was in place to keep the sand there was destroyed to put beachside housing on it.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#79

Post by pixl97 »

awestley wrote: post #67
pixl97 wrote: post #60

Earlier quoted context omitted.

>help protect the beaches more permanently. Then you get rid of the houses.... The shape of the shore is an equation. In it you have have a massive pool of energy that is the water and its currents. You have a second smaller, yet still massive in human terms, pool of energy in the wind. Then you have the slope of the land from a few miles on shore to many (maybe even hundreds of miles) offshore. This is the lever of…

That is why I said more permanently. 10 years is better than 72 hours. To say "get rid of the houses" as a solution to beach erosion without considering legal, social, and economic implications is a classic case of oversimplifying a complex problem.

At some point the bill needs paid, and like all moral hazards, this is one that foots the bill to someone else in the meantime.

Physics doesn't care about the dumb economic/political decisions you made in the past. Pushing it 10 years just creates 10 more years of damage to yourself and others and burns money the entire time.

You're acting like you can just science/money your way out of a problem that has grown massively over the last 70 years, but we no longer can. The bill is due with interest. Yea, you can roll over the debt if you want, but the house of cards falls down eventually.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#80

Post by pixl97 »

Veliladon wrote: post #40
tromp wrote: post #10

> Local news outlet Fox59 reported that the Republican state senator Bruce Tarr was working to secure $1.5m in state funding to replenish the sand. > Tarr, noting that a more permanent seawall was not an option because hard structures like these are not allowed on Massachusetts beaches If the only alternative is to drain state funds dumping tonnes of sand that quickly get swept away, then it's time to change the (by)…

It's because they're doing a shitty job of restoring the dunes. If you dump a ton of sand of course it's going to be washed away. There's literally nothing keeping it there. If they want to keep a dune there they have to rehabilitate the whole dune ecosystem and part of that is having an ecosystem between them and the ocean. If there were plants established and holding onto the sand they wouldn't be washing away in t…

Or to say it another way, they are spending $500k on a $5+ million dollar problem that requires buy in from a huge number of people over a long distance and to change behaviors of people using the beach to ensure they don't kill any plants and mitigations.
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