There are two reasons that it is fortunate that the death toll for Harvey is very low, compared to similar size storms at other times and at other places (zero at the time I first wrote this, a few confirmed, maybe ten or so suspected three days after landfall).. One is that all those people didn't die! (Obviously.) The other is that we can ask honest questions about this event, while the event is still fresh in our minds (and, at the moment, actually happening) with the intent of eventually seeking some clarity, without concern trolls biting at our ankles and telling us that we must wait until the hurt wears off before discussing the thing that hurts.
Harvey was windy and there was a storm surge. Anything that got knocked down in the Cat II or above winds, and anything destroyed by storm surge, was pretty much doomed or near-doomed, and we simply hope and perhaps assume that insurance covers that, and insurance rates would not be affected by such damage given that this insurance was sold in a hurricane zone, and thus properly priced. Right?
But the flooding related damage may require some 'splaining. Harvey is producing what is being referred to as unprecedented rain, and Harvey is staying in place for an astonishing and unbelievable amount of time, and this is causing some areas to be flooded with many feet of rain because the rain came out of the sky and caused a flood.
However, that is not really what happened. First, there have been rainfall amounts greater than anything we've seen with Harvey before. Second, hurricanes and tropical storms are known to stall, in fact, they do so fairly often. Third, beyond the empirical fact that such high rates of rainfall have happened before, science knew all along that a scenario like this was not only possible but given a reasonable amount of time, inevitable, because climate scientists can run models that are very good at informing us about possible futures.
So what, you may say. It is still a disaster and it is no one's fault that this happened. To that, I say, sure, whatever you want to believe to get you through the day, I'm fine with that. But, notice that flooding requires two things. One is water in, i.e., from the sky or from upstream. The other is an inability for the water to leave. The first factor is an act of the (human-changed) weather. The second factor is often very directly human. Humans can do two things. They can build drainage systems (or fail to do so) that can handle the very rare but very large flood, and they can avoid hardening the landscape into solid form (rooftops and parking lots, etc.) in a way that changes flooding patterns to make floods much more likely. It is my understanding that the latter happened in Houston.
Which brings us to the key question: What caused this area of Texas to get stupid about floods? Did everyone decide a long time ago to ignore science? Did everyone decide to spend their money on candy and gum instead of infrastructure? Did the good people of the Lone Star State and its various counties and cities implement reasonable science based policy, then elect a bunch of officials who took bribes or other emoluments to provide exceptions to those policies?
Or, maybe, we're talking Canadian Province here. None of it. Maybe Texas did all it could, decreased the likelihood of flooding rather than increasing it, and everything is fine. That's not what I hear, but maybe what I hear is wrong. That is why these are questions, not answers. I hope that we eventually get the answers.
In the end, will it turn out that Harvey is an example of failure of the assumption that we'll adapt to climate change?
Added: This conversation is now beginning to happen more broadly, with major news outlets noting that Houston is proud of it's Libertarian zoning laws.
They will never adapt to the climate change until they are forced to. Like Florida, how many texas homes are circular or geodesic domes? So that the winds go around instead of thru? How many homes will be rebuilt with their height based on the flood waters? Like in OK, or kansas how many earth homes are there to allow tornadoes to flow over them rather then knock them into the next state? Adapt?? Ha!!!
Your fifth paragraph is saying I think the opposite of what you intended. "They can build...they can avoid..." Two good things presumably. Then you say Houston did the latter.
Yes. Yes it is.
" Second, hurricanes and tropical storms are known to stall, in fact, they do so fairly often."
Wasn't that the point with Sandy and why despite being Cat1 it did so much damage (that and its extent).
I don't think that people in general are known for long-range planning -- especially if it causes taxes to go up even a miniscule amount. Most people seem to think that the 100-year flood used for flood planning and insurance purposes is long-term planning even though many people live into their 80s and 90s today.
Drainage is driven by gravity and thus determined by slope angle. In the Gulf Coast area of the U. S. most of the land is flat enough that streams are not particularly fast flowing and easily overloaded by rain. Street drainage is often worse because most development restricts the amount of ground into which rain can soak. To make matters worse, significant parts of the Gulf Coast are subsiding for natural and human-related reasons. (This is apart from the ongoing sea level rise.)
Basically, little that would be involved in protecting Houston and other Gulf Coast cities from moderately rare or worse rainfall and wind events is easy, cheap, and fits in with what seems to be the normal human approach to land use and land ownership.
Part of the issue is that when the cities were founded the issues were not know, consider Naples, It, San Francisco, and Houston, all were founded before folks really knew of the risks of the location as was New Orleans. The flood control district has begun in the last 15 years digging retention ponds to hold excess water, but a lot of Houston was built up before then so that there is no space to put retention ponds in. Of course major floods downtown in the 1920s lead to the construction of 2 major flood control reservoirs way west of the city limits back then. But over time the city has surrounded the reservoirs. At 20+ inches of rain there is not much that could be done, other than perhaps putting all houses on barges, that could float up as needed.
Note on those discussing evacuation you can' t really evacuate 6 million people in 2 days, in particular with one of the major evacuation routes being closed (i 10 west). due to the storm center being expected to pass there.
#1: I used to live in Kansas so I can tell you that people there are not, in general, any less intelligent than they are anywhere else I've lived (4 other states and a Canadian province). I can also tell you that circular or domical houses are not common (I'd be surprised if there were any). This is probably because it is not just houses that would need tornado-proofing, but garages, barns, schools, hospitals, fire & police stations, banks, and stores. Also, living even partly underground has its own problems.
#7: It's as you say.
It may be obvious already but anything like a reservoir, retention pond, or floodway that is placed outside of a city is almost bound to be overtaken by suburban sprawl as long as the population is growing and/or city centers are removed from the housing pool in favor of offices, public buildings, etc.
In a sense, Houston is paying the price for its own success as a people magnet.
Wihat will it take for the republican party in the USA to acknowledge what the rest of the world has known for some time that gobal warming and climate change is here and its nots going away such ignorance is hard to understand against such overwhelming evidence
I think it's a bit early to say that the death toll is minimal, basic services and transportation have been disrupted across an incredibly large region, and more people may (probably will) die before they are adequately restored.
But yes, it is evidence that people didn't take floods seriously as they built and developed. I don't get buying flood property, personally, but I guess if it's the only thing you can afford, you have no choice.
#4: Sandy moved through relatively quickly, but it was incredibly powerful despite relatively low wind speeds. The barometric pressure in the heart of Superstorm Sandy at landfall was just a few millibars above Harvey's eye at landfall, which allowed for a massive storm surge, FEET above any previous records, thus demonstrating that wind speeds alone are an inadequate measure of destructive potential.
"but I guess if it’s the only thing you can afford, you have no choice."
It's not the fault or even the choice of the buyer. Builders decide to buy up land to build and they will pay less to construct on a flood plain than on steeper ground above. Which means for the same cash they can build more houses and sell them for more cash.
It's not "if that's all you can afford", it's "Where are builders putting the goddamned houses".
The TV news head just informed me that Houston has no zoning laws. Is this true?
Anyhoo, re: retention ponds, I don't know about Houston's situation but things like golf courses can be designed to do double duty for flooding. Of course, zoning might help... rain absorbing asphalt and materials, growing upward density control...
Urban planning, It's actually a thing.
Re # 11 there is no such thing as higher ground in Houston, the highest elevations in town are freeway overpasses.
Also there is another question, if this is as many have suggested a 1000 year flood (.1% chance per year) is it worth it to prepare for it? In particular if the average house lasts say 50 years or so. Of course in buying a house if you want to you can check flood maps etc to see where the property lies. No one holds a gun to your head to buy in a flood plain. A number of the places that were flooded where flooded before so (perhaps the water was not as deep in the but they were flooded) Realistically at 25+ inches there is no part of Houston that will not flood.
#12 "if this is as many have suggested a 1000 year flood (.1% chance per year) is it worth it to prepare for it? In particular if the average house lasts say 50 years or so. "
That's a very good question and it applies to large earthquake and volcanic eruptions even better than to floods because in many areas there are few little examples between catastrophic events. A follow-on question is: What are you likely to lose if you aren't prepared and the rare event does happen?
I think you may be underestimating how long houses and other buildings can be expected to last. If you are not living in a real boom town, I think you would find that houses -- if not razed to make way for something else -- last closer to 100 years than 50 and larger buildings tend to last even longer -- if allowed to do so.
I used to teach an environmental geology class and I found that there is a lot of geological ignorance among even supposedly educated people. I have seen places where houses were built on landslides that were still moving (slowly) while they were being built -- and people bought them! Many people have a fatalistic view of natural hazards largely due to not really understanding the true scale of hazards that exist and the reasons and kinds of places in which those hazards occur. So, they have little idea of how to protect themselves. . .
...[I]f this is as many have suggested a 1000 year flood (.1% chance per year) is it worth it to prepare for it?
This question misses a fundamental point, which is that the '1 in 1,000 year' descriptor is with respect to the historical record, and has little bearing on the future probability of these events as human-caused global warming kicks in with gusto as a consequence of fossil fuel emissions. Such events will become '1 in 100 year' or 1 in 50 year' or '1 in 10 year' events. And even if it's closer to '1 in 100 year' than to '1 in ten year' probability for particular phenomena and particular locations, the cumulative cost of the even only slightly greater frequency/ slightly greater destruction/ slightly greater affected ranges is such that the cost may well be unbearable. As with thresholds physiological and ecological, the difference between economically-sustainable and economically unsustainable costs can be slight - heck, this is something that even 20th century capitalist economists grok, despite their penchant for externalising things that don't matter to them.
Many years ago I took umbrage with some engineers and local government politicians who were (admirably) planning for local sea level rise. They were speaking in terms of preparing for 1 in 100 year events, and had mapped the local impacts based on this classification. At the end of their presentation I asked them why they had used the old temporal classification rather than mapping impact against height above current sea level, and for a moment they stared at me and at each other because didn't understand the problem. So I pointed at a low-lying river-side suburb on their map and said "you're doing [x, y, and z] to prepare for a 1 in 100 year flood, but at what altered frequency do you expect this level of flooding to occur in the future? And how does that future frequency of flooding affect your preparation?" The dawning understanding on their faces was amusing to see, but their immediately-following discomfiture at realising their oversight was saddening.
I think that this jurisdiction responded to this context going forward, but I know that many others still don't get the difference.
" if this is as many have suggested a 1000 year flood (.1% chance per year) is it worth it to prepare for it?"
It's not a 1000 year flood any more. It's a 20 year flood at best.
And it illustrates the deniers penny wise, pund foolish economics: AGW mitigation will cost massively therefore we should not do anything except mitigate. But mitigating means to begin with spending to protect against a 1000 year flood happening every 8 years.
But to the same deniers, that costs money and doesn't need to happen.
Proving their "adapt and mitigate" is really "deny deny deny".
PS the USA is bigger than Houston, and the problem with cheap-ass builders building on flood plains for the profits (they're not going to get flooded out there) is worldwide.
"I have seen places where houses were built on landslides that were still moving (slowly) while they were being built — and people bought them!"
You presume the buyers knew.
And since housebuying is a good way to money launder and remains a "paper asset" even if it isn't actually sellable at the list price, the wealthy use house buying as collateral for cash to loan money they can actually spend at a lower rate than others, the buyers may never live there at all. Though they would presumable also care about the landslip if they knew about it too. No good if the asset disappears in 10 years. 20, not so bad: get a loan secured on that asset and let if fall into the void as the bank's problem.
Houston has been through at least one similar event in the last 20 years: Tropical Storm Allison in 2001. That storm dumped as much as a meter of rain in parts of southeast Texas, including Houston, which got more than 900 mm. The name Allison was retired after the 2001 hurricane season.
Some lessons were learned from Allison: hospitals in the Houston area no longer put their emergency generators at or below ground level. But other lessons were not: suburban areas have expanded to the north and west, meaning that even more of the upstream watershed is impervious than it was in 2001.
To those who think it aint the home owners problem....
When my daughter went to get her own home she had her husband check all past recorded floods, hurricanes, other stuff in the various areas they liked and then CHOSE not to buy in the local flood plain, not to buy where tornadoes and hurricanes were reported. But we were not able to build a geodesic NOT because of cost (they are slightly cheaper) but because the DAMNED ZONING RULES of the bigoted aholes nitwits would not permit it!! But she chose a place slightly down hill and all tornadoes & other high wind problems go right past us as does all rain water. And yes earth homes have their specific problems just as ALL homes have their specific problems, but the BIGGEST problem is damned zoning rules!!!
Ah, right. It's not the builders because zoning rules.
You'll need to explain what on earth the zoning rules are that have made you assert it is the home owners problem.
Or rephrase it so you stop blaming homeowners (which include now your daughter) for zoning regulations.
There are places in this country, many if not most places, where long term planning to address flooding has been carried out. Houston is singular in giving almost no attention to this problem.
A good part of the flooding in Houston is libertarian plain and simple.
Which state has passed a law saying that there cannot be any planning based on climate changing and legislated away sea level rise?
Or is that more than one state now?
Wow, something like that has occurred, off the top of my head, in one of the Carolinas, Florida, Texas.
Re # 19, even in most subdivisions in Houston you would be barred by the deed restrictions requiring the HOA approval of plans for housing. If the neighbors don't like the looks, you can't build it. Approval is even needed for the color of the roof. Have to get out of incorporated areas and onto raw land to have some chance of building, but these areas are decreasing with the increasing set of building codes.
So more than one.
A lot of the choices are made on behalf of powerful nongovernmental interests.
So those zoning laws? Check who wanted them. Builders? Estate Agents? Businesses? Car manufacturers (if your shops have to be three miles from the homes of people shopping there, car use will skyrocket)?
Even the ideology takes a backseat to power interests. Evangelists ignored their ideology to get behind Trump. Meanwhile the Mormons looked at the orange tango and despite being deluded by faith too, HELD TO THEIR IDEOLOGY and said hell no.
When it comes to ideology, as with good programming design, you should be stringent in what you do and accepting of what others do.
So here the mormon faith did better than the evangelicals.
Zoning codes do contribute to a lot of problems in many places in the US, but not in Houston, which rather infamously doesn't have zoning codes. HOAs can be a problem, and those do exist in Texas, but there are neighborhoods that don't have HOAs.
The main problem is that too many of the people involved are in it for a quick buck. The builder buys the land and builds houses (or a shopping center) on it, and at least in the case of residential development sells the houses to would-be homebuyers, after which it is no longer his problem. The taxing authority gets a boost in revenue in the short term, and doesn't always think 20 years ahead to the expenses of maintaining the infrastructure, which the tax revenues from US suburban style development are usually not enough to cover. The banks bundle the mortgages and sell them off to investors, at which point it isn't the bank's problem either. When things go drastically wrong with that process, it's usually the homeowner who is left holding the bag.
There are federal guidelines that are intended to discourage development on flood plains and other particularly disaster-prone areas, but there are two problems there: (1) these are guidelines, and while there are carrots and sticks involved (e.g., it's considerably harder to get a mortgage for a house in a flood plain) a sufficiently motivated developer will ignore them; and (2) there is only so much that can be done in a place with as little topographic relief as the Texas Gulf coast. In Houston there is no downhill for the water to flow.
Coastal North Carolina (the state that banned municipalities and counties from considering any sea level rise beyond linear extrapolation of what was observed in the 20th century) has similar issues: very little topographic relief in that part of the state, and very hurricane prone. They haven't had anything on this scale, in part because they don't have big cities on the coastal plain (Charlotte and Raleigh-Durham are far enough inland to have some drainage), but North Carolina has seen extensive post-hurricane flooding.
As for economic matters, at least New Orleans has a good reason for being where it is. A lot of US-made goods, including a significant fraction of the world's food supply, moves by barge along the Mississippi River and its major tributaries. To be exported, that cargo has to be transferred from barges to ocean-going vessels, and New Orleans is the port where that happens. (Montreal plays a similar role in the Great Lakes/St. Lawrence watershed.) You can argue that we should move those facilities upriver to Baton Rouge or thereabouts, but the port has to be somewhere.
The Port of Houston was developed primarily to serve the oil industry. That's why so many refineries are clustered around the port. It made sense when Texas was one of the world's leading petroleum producers, but today it is possible to build pipelines to put that port in a less disaster-prone part of the coast, and with much of North America's oil production coming from places well inland such as North Dakota and northern Alberta, it's worth looking at other places to put that infrastructure.
Close it down.
Cheaper and it gets the right thing (reduction of CO2) done. It also prevents leaks. No pipeline, no leaks.
In a state where used to work, county commissioners of a county issued building permits. A friend of a commissioner wanted to build a house on a levy so he would have a good view of the river. The house had a basement with a daylight wall on each side of the levy. The river flooded and you can imagine what happened. The house was still standing but part of the town was flooded.
#17 "You presume the buyers knew"
I guess I wasn't clear. I presumed no such thing. What I did presume was that the buyers did not have enough education to even know to look for indications of mass movement -- or know what to look for.
In the U. S., geological concepts and information are taught in elementary school, in some high schools, and is an elective in college for everyone but geo majors. So many adults have an essentially pre-19th century outlook when it comes to evaluating hazards such as weathering, erosion, flooding, earthquakes, volcanism. Some, of course, develop some practical knowledge from bitter experience. In our states' rightsy country not all states have any useful requirements related to siting of buildings etc. to avoid the most likely geohazards. Maybe it's different in the UK.
#27: "... but the port [of New Orleans] has to be somewhere."
Yes it does. It is surrounded by levees about as high as they can be built. Inside, much of it is lower than mean sea level and normal Mississippi River level. When it is destroyed either by flooding from torrential rains (Katrina), the sea via Lake Pontchartrain (Katrina), or from the river (the levees there were nearly overtopped in the 1970s), it will have to be rebuilt.
In hindsight, levees were a bad choice for the long term, When floods were prevented from spreading out into the city, some of the sediment was deposited in the channel bottom itself, thus raising normal river level. The levees were raised and the same thing happened and so the present situation evolved. In addition to that, New Orleans is sinking along with much of the Gulf Coast and, of course, sea level is rising by thermal expansion and addition of meltwater.
New Orleans is worth seeing -- a lot of people love it -- but I'd suggest not putting off a visit too very long. .
Re #31 the issue again is when the town was first settled, it was only along the mississippi and did not go to far into the swamps. Interestingly there is a 45 foot deep channel to Baton Rouge so you could move the port up river. Actually the scenic part of New Orleans (the french quarter) is not the part of the city most subject to flooding, it is rather the parts on the north side of town that are already below sea level.
"Actually the scenic part of New Orleans (the french quarter) is not the part of the city most subject to flooding, it is rather the parts on the north side of town that are already below sea level."
Right, the French were a bit more realistic when they settled the city ...
"As for economic matters, at least New Orleans has a good reason for being where it is. A lot of US-made goods..."
US-made goods have nothing to do with why New Orleans is where it is. French trade, on the other hand ...
Most species adapt to changing climate by going extinct.
#32:"Actually the scenic part of New Orleans (the french quarter) is not the part of the city most subject to flooding, it is rather the parts on the north side of town that are already below sea level."
There are certainly lower and higher parts of N.O. but I remember standing on a terrace of a building by the river where I could seen over the levee. It was clear that the river level was above the level of the streets. A levee breach there would be catastrophic.
Of course the city began on the natural levees but there was not enough room there for the population that collected around the major port it became. The major building of levees along the lower Mississippi was triggered, if my recollection of history is correct, after the disastrous flood of 1927. When faced with an invasion, people tend to build a high wall. It is not always the best choice.
You are probably correct, Baton Rouge may well become the next major port on the Gulf. As sea level rises and the SE LA parishes become completely submerged there will be no alternative. N.O. will probably be just a legend by the 22nd century.