Climate Resilience Summit Part 1
Despite us being bombarded with the climate change message, the Climate Resilience Summit in Boston taught us something new and shocking: The first cities, such as Boston, are already experiencing climate-related water issues. By 2030 (!) it is likely that significant portions of these cities will be underwater UNLESS they fight this problem on all fronts.
We need many approaches to mitigating climate change effects, and detention-based green roofs are one efficient solution to prevent floods; intercepting stormwater as close to the source as possible: on the roof.
The Dutch at the Boston Climate Resilience Summit
The Dutch have a long history with water. Large parts of the Netherlands are below sea level, and the inhabitants are fighting a continuous battle against water. But they have also learned how to utilize it and make water an asset. The Dutch have thus become a world leader in stormwater management issues.
Hence, the Dutch government sponsors the Climate Resilience Summit in Boston. In this meeting, they bring local decision-makers, policymakers, and those in the trenches that deal with climate change, together with solution-based Dutch industry, researchers, and policymakers to find opportunities for collaboration.
This was an eye-opener.
The thirst for answers is huge. The willingness to learn on both sides is beyond evident, and the eagerness to try out new solutions is clear. Boston is in trouble, and they know it. This is how:
Boston, Massachusetts, has a massive tidal shift. The water level in the harbor goes up and down by 3-4m (10-14feet) twice a day.
When they took us to the 1st meeting on Wednesday, they showed us the water level in the Boston Harbor, and at high tide, the water is only 1m (3ft) below the edge/curb of the city. That means at high tide, a small wave made by a midsize boat can cause the wave to go over the wall and cause a mini flood. This turned out to be the same in Portland, Maine, the second city that was also present at the event.
Bigger and more intense storms combined with low tide.
Every city manager we met stated loud and clear that they are seeing storms the last 5-7 years that rarely, if ever, took place prior. Emergency road closures, previously implemented once a decade, are now as frequent as 1-2 times per year.
Every time a big storm coincides with low tide, the water can more easily be dumped into the rivers and harbor as the water level from the flood pipes, streets and rivers are much lower than the sea level.
Flooding that only occurs in the bottlenecks of rivers, plumbing system, and some lower-lying areas of the city, are still severe but manageable from a cost and damage perspective. These events are relatively short and have physical property damage but do not do severe economic damage.
But that is not the case when the tide is high.
Sea level rise combined with bigger and more intense storms.
The ’perfect storm’ is a series of events where all events happen at once, and they exponentially increase the problem.
Exceptionally high tides are sometimes referred to as King Tide and can cause “sunny day flooding.” A King Tide is a naturally occurring and predictable events but combined with North Eastern storms large volumes of water can be pushed upward and inland, into the harbor and onto land.
The King tide happens several times per year, but any high tide that lines up with a North-Eastern storm every few years or so will cause trouble. During these events, rivers can no longer dump their access water as the ocean pushes back. The result is that the drains flood in the wrong direction, into the city, especially as the street level is equal to or below sea level.
In this scenario, even a moderate storm causes flooding, and a large storm causes the city to completely shut down. For days, or weeks!
Besides the astronomical damages to physical property, the economic damages to the cities caused by people not being able to go to work, restaurants that cannot open, or hotels that cannot operate, billions of dollars are lost.
Quite a few AI (artificial intelligence), and software companies are mapping these economic impacts as these are much more severe than any physical damage, so policymakers receive better datasets to understand what happens how and when. These same tools allow them to explain better to their constituents what climate change will mean to their citizens, how to react, and how to change the city going forward.
Boston and Portland sea level rise and flooding risks
Boston and Portland, ME Maps show what a 0.3m (1 foot) sea-level rise by 2030 combined with a 1% probability-storm, previously known as a 100-year storm, will do to your neighborhood.
When you see that just your neighbor’s houses close by the water are flooded and your house or office building is safe by being a mere 60m (200ft) away from the flood line, you pay attention. But upgrade the storm to a 0.2% (500-year) storm, or you move the dial to 2050… Now you and your neighbors living 600m (2000 feet) behind you are all underwater with 1.5m (5 feet) of water on your main floor.
Next, you look at the expected water levels in 2070. Models show anywhere from 0.9-3.7m (3-12 feet) of sea rise at high tide in Boston and Portland, Maine. Now you see levels of disaster that can no longer be deemed remotely acceptable.
It means permanent flooding in some areas and monthly floods in other areas. It requires preparation and changes even at the most conservative model outcomes. It's humbling to see that a city can be brought down to its knees by climatic change.
For those of you who do not understand how water levels can rise so quickly, its more than simply melting ice, its mostly a matter that warmer water (even ever so slightly) expands its volume. A liter of physical water no longer fits into a liter cup if it warms up, and it spills over the edge….it rises the sea level.
Protecting Boston and Portland from flooding
In an effort to interject some good news into this story, we went onto a boat tour to the Boston Sewage treatment plant on Deer Island located a few miles away from Boston.
There we got a tour that showed that Boston in the ’80s had the worst harbor water quality in North America, combined with the worst drinking water quality. They had a dysfunctional sewage treatment plants, leaky septic systems, and sewage overflows. On top of this, they dumped all sewage straight into the Harbor for decades which had slowly killed but all the marine and plant life. It was a dreadful pit.
Public outrage and forward-thinking policymakers took on the battle in the late ’90s to clean up the water. They built a state-of-the-art sewage treatment plant and created public awareness. Now 20 years later, by all metrics, they have cleaned up the harbor! Boston is now the leader in North America as having the best drinking water, and the cleanest surface/harbor water in the nation.
They went from worst to best in less than 20 years. It required a disaster, public awareness, and commitment - but they did it. It also shows what can be done if there is public and regulatory support.
Problems can be solved!
Don’t miss part II of this article series on the Climate Resilience Summit in Boston, 2019:
Digital Twin Cities – the Magic Mirror of Stormwater Management
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