Hurricanes, and the curve of forgetting.

[conehead433]

The Ebbinghaus Forgetting Curve and how it apparently applies to hurricanes. When a memory is reinforced with some regularity a person reacts in the manner in which the memory has been reinforced. Occupants of a number of Florida cities have been hit so often by hurricanes that their reaction to an oncoming storm is to get out. I'm mentioning this because the residents of Texas who were in the path of Harvey for the most part didn't feel the need to get the hell out. But I'm not going to claim that that these people were stupid, in spite of the overwhelming evidence that when a cat 3 or greater storm is approaching, that you should evacuate. It had been so long since this area was hit by a strong storm that none of these people had any memory reference of having gone through such a storm. You would think that the aforementioned group of people would have, for the most part, at least seen footage of the damage and devastation caused by Andrew, Ivan, Rita, and Katrina, et. al., and that they would have known they should have gotten out of the area. So why do humans need to live through storms like this to even begin to understand the need to get away when they happen again? Makes no sense to me at all. My thoughts and prayers to the victims who were unable to get away, and to the first responders and medical personnel who stayed to provide assistance.

 

[UglyCasanova]

Lack of resources both in terms of transportation out of the city or anywhere to go to. Fear of looters. And fear of the chaos that an evacuation would entail.

 

[Zorba]

They did evac for Rita. Huge cluster and many people died on the roads, then there was little damage to Houston. So that is what people remember. The areas near the eye did evac, though.

 

[TastesLikeChicken]

Meh. I've lived in Florida on and off for over 45 years, mostly on. I've been through plenty of hurricanes, including Charely in 2004, whose eye went right over my house. In the vast majority of cases the hurricanes were over-hyped; way, way over-hyped. The vast majority were nothing but minor storms.

Harvey was/is an anomaly. Katrina was another anomaly caused by local conditions and a compilation of unforeseen events. People take chances on these storms and it's always a gamble, though most of the time it's a gamble that isn't lost. Harvey and Katrina were lost gambles for a few.

But people will focus on those who made bad choices, not those who made good choices.

How many escaped Harvey?

 

[JSt0rm]

God hates texas

 

[Puffnstuff]

Normalcy bias is present in every facet of modern civilization. There is some personal responsibility involved with a situation like this one and if you live in a flood plain then you have do decide what is more important and let that guide your decisions. TX DOT should do more on the highways and install flood water warnings to alert drivers to the presence of water on the roadway that will flood them out and people should be smart enough not to drive into deep standing water.

My first big storm was Camille and I was on the eastern edge of it in NW FL and things got plenty rough for us. I lived in Pensacola when Ivan rocked our socks off in 04 and suffered structural damage to my home and property. The following year when the next one showed up, Dennis, I was sitting in Jax drinking coffee and watching Anderson Cooper on CNN describing his experience there. When I got back home everything was okay but it did lean one of my oaks over just a bit more than Ivan did. People have to make choices for themselves and take responsibility for them. I really feel for elderly and disabled people in those nursing homes who are at the mercy of their caregivers.

 

[Jaskalas]

You would think that the aforementioned group of people would have, for the most part, at least seen footage of the damage and devastation caused by Andrew, Ivan, Rita, and Katrina, et. al., and that they would have known they should have gotten out of the area. So why do humans need to live through storms like this to even begin to understand the need to get away when they happen again? Makes no sense to me at all.

The day it made landfall, Harvey started off as a Category 2 storm in the morning. Grew to Category 4 through the day when it was too late to evacuate. The rain and wind begin hours ahead of the storm. Second, most storms blow through quickly. Leaving little more than a minor nuisance to the many people not on the coast or directly hit by Hurricane force winds. This one stalled in place... bringing once in a life time flooding.

When making their decisions, people probably saw a tropical storm the day before, a weak Hurricane the day of... Their inability to process the risk has its reasons. Hell, how many truly paid attention? Go back and watch the local news the night before. That'll tell you the sort of details low information folks had to work with.

 

[HomerJS]

Remember when right wing evangelicals blamed hurricanes and other disasters on gay people? Don't think you'll be hearing that kind of rhetoric from the left claiming Charlottesville precipitated Harvey

 

[Puffnstuff]

Remember when right wing evangelicals blamed hurricanes and other disasters on gay people? Don't think you'll be hearing that kind of rhetoric from the left claiming Charlottesville precipitated Harvey

Yep and it was primarily televangelists doing it the likes of which you can find on TBN talking out of both sides of their mouths.

 

[GoPackGo]

Remember when right wing evangelicals blamed hurricanes and other disasters on gay people? Don't think you'll be hearing that kind of rhetoric from the left claiming Charlottesville precipitated Harvey

But, oh, wouldn't it be fun?

 

[GagHalfrunt]

The Ebbinghaus Forgetting Curve and how it apparently applies to hurricanes. When a memory is reinforced with some regularity a person reacts in the manner in which the memory has been reinforced. Occupants of a number of Florida cities have been hit so often by hurricanes that their reaction to an oncoming storm is to get out. I'm mentioning this because the residents of Texas who were in the path of Harvey for the most part didn't feel the need to get the hell out.

There's a hell of a lot more to it than just memories of past events. For the majority of people the instinct is to stay and protect your property. Given the huge number of people caught in the paths of these storms the death and serious injury toll is very low. And most believe that the odds are with them and that being in their own home is important. If a window gets broken or flooding reaches a door there's some benefit to being there to deal with it. Boarding up a broken window or sandbagging a breached door at the height of the storm can prevent serious damage. Granted that's not the case when the water is up to the eaves of the house, but the desire to stay and fight to fend off worse damage is based in reality. It can and in many cases does help.

 

[Zorba]

There's a hell of a lot more to it than just memories of past events. For the majority of people the instinct is to stay and protect your property. Given the huge number of people caught in the paths of these storms the death and serious injury toll is very low. And most believe that the odds are with them and that being in their own home is important. If a window gets broken or flooding reaches a door there's some benefit to being there to deal with it. Boarding up a broken window or sandbagging a breached door at the height of the storm can prevent serious damage. Granted that's not the case when the water is up to the eaves of the house, but the desire to stay and fight to fend off worse damage is based in reality. It can and in many cases does help.

People also generally feel the most safe at "home" and people will take great risks to get back to their home or stay at their home in major storms. I live in OKC, and every year people leave my office building, that has 8" concrete walls, blast doors, steel frame. To drive home during a tornado warning, so they can be at their house.

In aircraft safety, it is well known one of the best indicators of whether or not a pilot will turn around when an incident happens is where his car is parked.

 

[Paratus]

Having lived in Houston through Tropical Storm Allison, the Hurricane Rita evacuation, Hurricane Ike, and now Hurricane Harvey I feel I can shed some light on the decision to stay or go.

We stayed for Allison and Harvey. We evacuated for Rita and Ike.

The evacuation for Rita was awful. A major portion of Houston tried to evacuate and several people died. Our 3 hour trip to San Antonio took 14 hours. The 5 hour trip to Dallas took 40 hours.

Evacuation for Harvey wasn't possible. The area that is currently under flood warning is the entire Houston metro and surrounding areas. You'd have had millions stuck on the same roads that are now flooding.

There is no easy way to decide to evacuate or not. It's always a risk trade.

 

[K1052]

It is a practical impossibility to evacuate the Houston metro on short notice. The only way to address the threat long term is probably massive spending on water management and dramatic changes to planning/building codes.

 

[Puffnstuff]

It is a practical impossibility to evacuate the Houston metro on short notice. The only way to address the threat long term is probably massive spending on water management and dramatic changes to planning/building codes.

So very true not to mention the fact that Houston is 50ft ASL which adds to their woes. Not enough contrast in elevation for the water to drain away effectively means they will have persistent water for a longer period of time. Even if they had massive pumping stations where would they pump the water to? They would need many miles of pipeline to push that water away from the region so it didn't rush back on them in short order.

I wonder what it would cost to build new reservoirs west of that area in the desert plains and then pump excess water to them?

 

[Zorba]

So very true not to mention the fact that Houston is 50ft ASL which adds to their woes. Not enough contrast in elevation for the water to drain away effectively leaves they will have persistent water for a longer period of time. Even if they had massive pumping stations where would they pump the water to? They would need many miles of pipeline to push that water away from the region so it didn't rush back on them in short order.

I wonder what it would cost to build new reservoirs west of that area in the desert plains and then pump excess water to them?

The problem is pumping anywhere near fast enough to make any difference. Many of the rivers in town are flowing at over 20,000 cubic feet per second. A 20 foot diameter pipe would have to flow at 45 mph to match that capacity. I think several rivers are higher than that too.

People vastly underestimate the amount of water flowing in flooded rivers.

 

[K1052]

The problem is pumping anywhere near fast enough to make any difference. Many of the rivers in town are flowing at over 20,000 cubic feet per second. A 20 foot diameter pipe would have to flow at 45 mph to match that capacity. I think several rivers are higher than that too.

People vastly underestimate the amount of water flowing in flooded rivers.

Yea for this application pumping is pointless. A large diameter gravity fed diversion scheme is one of the few options that I can see as even possibly workable. They make 60ft diameter TBMs now so building such a thing isn't impossible, just expensive. You'd still need major changes to future construction and planning in the metro to avoid making the existing problem worse.

 

[Puffnstuff]

There's always an engineering solution to problems. It would take several pumping stations with high capacity pumps to move enough water to make a difference but evacuating some water is better than just allowing it to continue spreading. This situation should be a use case justification for constructing a better methodology for flood mitigation. It may come down to codes changes to prohibit on slab construction with a minimum height to get structures higher off the ground in the lowest lying areas.

 

[K1052]

There's always an engineering solution to problems. It would take several pumping stations with high capacity pumps to move enough water to make a difference but evacuating some water is better than just allowing it to continue spreading. This situation should be a use case justification for constructing a better methodology for flood mitigation. It may come down to codes changes to prohibit on slab construction with a minimum height to get structures higher off the ground in the lowest lying areas.

The largest pumping facility I'm aware of is at the West Closure Complex near New Orleans and can only move 19,000 cubic feet per second at full capacity, costing $1B to construct. A number of rivers around Houston seem to be generating flows that are several times that. Money is probably better spent with passive diversion works that can handle much higher flow.

 

[Puffnstuff]

Money is probably better spent with passive diversion works that can handle much higher flow.

That works each spring with the snow melts but our source is stalled out over the victim in an area with relatively little elevation change so some form of active mitigation must be used. Personally I believe that those reservoirs should've been drawn down prior to landfall to help make some room for the forecasted precipitation.

 

[SMOGZINN]

That works each spring with the snow melts but our source is stalled out over the victim in an area with relatively little elevation change so some form of active mitigation must be used. Personally I believe that those reservoirs should've been drawn down prior to landfall to help make some room for the forecasted precipitation.

The problem is that there is nowhere to pump the water too. The water normally flows out to the Gulf, but with a hurricane in the Gulf it is pushing all that water back towards the city, causing all flood prevention methods to fail. Pumping the water North or West just causes it to flow back towards Houston. There was literally nowhere that Addicks Reservoir or Conroe Reservoir could be drawn down to that would not have made the situation worse.

Furthermore Addics was actually really low already. Here is a graph showing it's levels over the last week.

 

[K1052]

The problem is that there is nowhere to pump the water too. The water normally flows out to the Gulf, but with a hurricane in the Gulf it is pushing all that water back towards the city, causing all flood prevention methods to fail. Pumping the water North or West just causes it to flow back towards Houston. There was literally nowhere that Addicks Reservoir or Conroe Reservoir could be drawn down to that would not have made the situation worse.

Furthermore Addics was actually really low already. Here is a graph showing it's levels over the last week.

These are kind of two separate but sometimes related issues. Storm surge, while a concern, isn't causing much in the way of drainage issues right now. FWIW there have been proposals to build what's called the "Ike Dike" which would have a closure structure(s) that would protect Galveston Bay from surge.

 

[GagHalfrunt]

So very true not to mention the fact that Houston is 50ft ASL which adds to their woes. Not enough contrast in elevation for the water to drain away effectively means they will have persistent water for a longer period of time. Even if they had massive pumping stations where would they pump the water to? They would need many miles of pipeline to push that water away from the region so it didn't rush back on them in short order.

I wonder what it would cost to build new reservoirs west of that area in the desert plains and then pump excess water to them?

The fundamental truth is that you can't plan for a storm like this, create the infrastructure necessary to deal with it and pay for all that when this is a once in a millennium event. Houston has some flooding problems, sure. But no amount of foresight or government spending could have prevented major problems with a storm of this magnitude. It's just an incredible fluke and if it happened almost anywhere else we'd be having the same amount of clueless Monday morning quarterbacking. Why wasn't Cleveland prepared? Why didn't Tallahassee evacuate? Why didn't Portland spent more on their drainage? Houston just got fucked by Mother Nature. A storm like this would have caused the same type of problems no matter where it hit.

 

[K1052]

The fundamental truth is that you can't plan for a storm like this, create the infrastructure necessary to deal with it and pay for all that when this is a once in a millennium event. Houston has some flooding problems, sure. But no amount of foresight or government spending could have prevented major problems with a storm of this magnitude. It's just an incredible fluke and if it happened almost anywhere else we'd be having the same amount of clueless Monday morning quarterbacking. Why wasn't Cleveland prepared? Why didn't Tallahassee evacuate? Why didn't Portland spent more on their drainage? Houston just got fucked by Mother Nature. A storm like this would have caused the same type of problems no matter where it hit.

This is fundamentally a dodge for the short sightedness of humans, particularly Americans in this case. Storms are nature but floods are man made since we alter the environment with sometimes very very poorly considered development.

 

[GagHalfrunt]

This is fundamentally a dodge for the short sightedness of humans, particularly Americans in this case. Storms are nature but floods are man made since we alter the environment with sometimes very very poorly considered development.

Right Right. And it's poorly planned development to build in earthquake zones. And it's poorly planned development to build in areas prone to wildfires. And it's poorly planned development to build in areas with blizzards, tornadoes, coastal storms, volcanoes, high winds or potential comets slamming into them. Are you seriously making the case that this is because Houston altered the environment and would have been just dandy if we had not "altered the environment"? There is not a city in the world that could have handled this in an unaltered state and none that has planned it or built their infrastructure to accommodate it. 100% of the cities on Earth would have been seriously screwed.