Managed Retreat
Jun. 28th, 2021 03:12 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png)
I'm pleased to see someone else admitting that not all cities can stay where they are. This article gives several examples of how cities could adapt to climate change, including the option of moving inland.
Some of these are viable solutions for problems like sunny-day floods, saltwater encroachment, or land loss.
However, none of them will defend against the increasingly violent storms that batter the coastlines. Those range for many miles inland. Some whole states are at risk, and many more have significant areas at risk. That's before accounting for the inland impact of hurricanes. Since human habitations require water and often hug the coastlines, a complete inland retreat is probably unfeasible. We'll have to figure out ways of coping with both floods and winds, which is difficult. But the farther from the coast, the better, for both of those hazards.
In order to choose appropriate response strategies, each city must look at its current and projected problems, along with its general needs and available resources. The bottom line is that a lot of people will have to move due to environmental foreclosure, and many more will have to change the way they do things. This can be done in safer, more logical ways through managed retreat or in risky evacuations as people flee just ahead of disasters.
Some of these are viable solutions for problems like sunny-day floods, saltwater encroachment, or land loss.
However, none of them will defend against the increasingly violent storms that batter the coastlines. Those range for many miles inland. Some whole states are at risk, and many more have significant areas at risk. That's before accounting for the inland impact of hurricanes. Since human habitations require water and often hug the coastlines, a complete inland retreat is probably unfeasible. We'll have to figure out ways of coping with both floods and winds, which is difficult. But the farther from the coast, the better, for both of those hazards.
In order to choose appropriate response strategies, each city must look at its current and projected problems, along with its general needs and available resources. The bottom line is that a lot of people will have to move due to environmental foreclosure, and many more will have to change the way they do things. This can be done in safer, more logical ways through managed retreat or in risky evacuations as people flee just ahead of disasters.
(no subject)
Date: 2021-06-28 09:22 pm (UTC)Well ...
Date: 2021-06-28 10:28 pm (UTC)However, there are many urban design techniques to cope with challenges, and these are often easier to build new than to retrofit. Examples include:
* porous pavement that lets water soak through
* rainwater harvesting so it can be used
* rain gardens to soak up water
* hugelkultur to direct, trap, and/or absorb water; one-plant pits can be invisible at the surface
* bioswales to slow runoff and minimize flooding or erosion
* swamp filters to clean runoff before it reaches natural waterways
* integrated stormwater management to fit all the pieces together for maximum benefit
Inland retreat will work best on areas of moderate slope, where moving a modest distance gains you a good yardage above the waterline. Where the coastline is very flat, it's not enough. Where the coastline is very steep, it's rarely needed unless the cliffs are crumbling.
Re: Well ...
Date: 2021-06-29 12:35 am (UTC)Unfortunately the newer construction has a much larger amount of pavement and much less porous surface or exposed dirt/vegetation. There has been a general level of disregard across the city even for what could be done easily. When new construction takes runoff and flood prevention into account it is in the form of culverts and holding ponds and cisterns which have specific limits to their capacity and as far as I am aware (and I did some study on this as a social issue while I was in grad school) there is not much being done beyond that.
I find it super frustrating that so much of what should have been done all along to prevent and mitigate these issues would have been relatively simple "common sense" kinds of things that mostly just require a dose of good planning.
Re: Well ...
Date: 2021-06-29 01:07 am (UTC)