Every aspect of coastal infrastructure will be impacted by sea level rise; and the sheer size of the problem is difficult to comprehend. We can’t just turn Venice, California into Venice, Italy; but there are things we can do to protect our coastal communities and infrastructure.
There are several places in the world where canals, not roads, represent the main thoroughfares — where front doors and shop entrances lead to boat slips and bridges, rather than driveways and parking lots. Venice, Italy, of course, comes to mind; along with Vietnam’s Hội An and Russia’s St. Petersburg, among other picturesque spots.
Denizens of these localities have adapted their transport, commerce, emergency services, policing and firefighting to these conditions; and go happily about their watercourses with little regard for their odd circumstances.
The rest of us have neither the inclination nor the aquatic wherewithal to navigate our towns, cities and hour-long commutes from the suburbs by water. Ye,t that is just what many of us will need to do when the predictions of today’s climatologists come to pass — a rise of between two and six feet is projected this century.
The current projected rise will have massive, devastating and planet-wide consequences. Two to three hundred million people are expected to be refugees of flooding and inundation — as the 90 percent of humanity living along the coastlines around the globe are assailed by rising tides, persistent flooding and unmanageable storm surge. Even non-coastal areas and low-lying riverine communities are expected to flood regularly.
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We normally think of this in terms of the number of dwellings that will be washed away and those made homeless thereby. Goodness knows that’s tragic enough, but our entire coastal infrastructure — not just individual holdings — are going to take a beating. A Stanford University study recently sounded the alarm about Northern California’s highway system: “the domino effect of flooding … is going to require a redesign of transportation systems as sea levels, storm surges and flooding worsen over the next thirty years. Otherwise, more extreme weather conditions could paralyze road transportation.” Yikes.
Many coastal cities have airports located as near as possible to the waterfront, with runways often just above the waves; and Resource Watch found that just one meter (3.28 ft) of rise (MSL), a conservative estimate, would drown approximately 80 airports worldwide. Indeed, Boston and San Francisco have erected seawalls in the last few years.
So far, this is all civilian stuff; but imagine a naval base immobilized by too much water. That’s what is now happening in Virginia at Naval Station Norfolk.
“The entry road swamps. Connecting roads become impassable. Crossing from one side of the base to the other becomes impossible. Dockside, floodwaters overtop the concrete piers, shorting power hookups to the mighty ships that are docked in the world’s largest naval base … all it takes to cause such disarray these days is a full moon, which triggers exceptionally high tides,” notes National Geographic. As sea levels continue to rise, the base is expected to “flood 280 times a year.” A 2016 report showed 18 other military installations around the United States that were at risk due to climate change impacts.
Homes and schools can be moved, though with much disruption — but a naval base is much harder. And then there are the critical situations we don’t even see.
Water resources may need to be rethought — as rising volumes of saltwater infiltrating traditionally fresh groundwater supplies could make many aquifers and drinking-water sources unusable without desalination. As the National Environmental Education Foundation reported this year: “The amount of saltwater infiltrating the (Biscayne) groundwater aquifer will increase, which can make the water too salty for human consumption.”
Less obvious but no less critical are the underground conduits: water, electric. Two years ago, researchers performed a risk assessment for fiber optic cable in the US and found that more than 4,000 miles (6,437 kilometers) of the stuff was at risk, especially around some of the larger cities such as New York City and Miami: “While the standard buried fiber conduits are designed to be water- and weather-resistant, most of the deployed conduits are not designed to be under water permanently,” as they would likely be under NOAA sea level rise (SLR) projections. Given the importance of connectivity — especially in emergencies — this is yet another significant risk.
Then there’s the problem of salt: “Sea level rise is not just a problem of water … imagine if saltwater flooded a farmer's field, or a coastal forest. Not only does the area have to survive flooding, but also a drenching in salt water that can kill plants and irreversibly alter soil chemistry. Saltwater flooding can mean death for these ecosystems. Already scientists have seen stands of ‘ghost forests’ where once-healthy trees were killed by saltwater flooding, and farmers' fields are being converted to tidal marsh and salt flats.”
Every aspect of coastal infrastructure will be impacted by sea level rise; and the sheer size of the problem is difficult to comprehend. Infrastructure is built locally, designed to last over time based on the conditions that obtain at the time.
Yet, how many communities have the resources to relocate their homes, businesses, roads, schools and emergency services; protect their farmlands, and raise their bridges and seawalls — in short, change their infrastructure from top to bottom?
We can’t turn Venice, California — which is at serious risk of inundation — into Venice, Italy; but there are things we can do to protect the people, and the infrastructure, therein.
It turns out there are three main strategies, which we’ll cover in a future article.