The other challenges from rising seas
To the editor:
Launch into a discussion about sea level rise, and the first thing that comes into focus is flooding. It’s the most obvious outcome of higher water levels, it carries a high risk for damage and impact, and it certainly would seem to be the biggest problem coastal communities would face.
Ah, but sea level rise will have a far more insidious impact that merely pushing more waters onto our coasts, rivers, wetlands and communities. There are some less obvious outcomes from any increase in sea level, some of which may have very far-reaching effects:
* Potable water could be harder (or more expensive) to find. Since almost every coastal community relies on groundwater to supply its potable needs, rising levels of salt water threaten to encroach on existing supplies, either turning them more saline (and thus undrinkable) or necessitating more treatment to make them safe for consumption an expensive proposition, especially if communities need to turn to desalination.
* Your coastal economy will take a hit, however it operates. If you rely on tourism, dwindling beaches due to higher waters will take its toll. Commercial fishing a big industry? Changing water conditions (salinity as well as temperature) could shift or shutter entire fisheries. Is agriculture a big player inland from your coast? The competition for usable water if groundwater supplies are sullied could stunt its growth. Even ports (and the shipments they handle) will need to adapt to changing conditions.
* Coastal habitats will change far more rapidly than their inhabitants might like. The slightest change in water conditions levels, temperature, salinity, even turbidity can remake a habitat almost overnight. Productive estuaries can go fallow, protective freshwater and transitional wetlands can turn tidal, nest and resting sites can dwindle and disappear and all the critters that rely on that habitat will come under increasing pressure as well.
* A community’s basic infrastructure will need to withstand much more to do its job. Beyond the obvious drainage systems that can’t drain because high tide is higher than it used to be the potential strain on coastal infrastructure from higher water levels, more exposure to saline water, more inundation overall, etc., is considerable. Add to this aging infrastructure and changing conditions possible with higher water levels bridges past their engineered life, roads more exposed to tidal influences, power grids and water systems having to operate under increasing adverse conditions and the problem becomes clearerand the cost to fix those problems continues to mount.
* Predictability will give way to uncertainty on too many levels. For coastal professionals, residents and advocates, this is the biggest concern uncertainty will have a major impact on our communities in an unpredictable way. From regular occurrences that suddenly turn from routine to ruinous, to weather events that veer from mild to wild almost instantly, to the long-term unknowns tied to sea level rise and the concurrent environmental changes that could remake coastal conditions for years (or more) to come. Something as simple (and crucial) as how the oceans circulate a process that moves more water than all the rivers in the world, according to studies is highly dependent on water temperature and salinity to function two conditions that have become impossible to predict (or even rely on) as ocean conditions change.
Why is this important to you? Because a majority of Americans live within 50 miles of a coast, and the coastal economy generates more than half of the country’s Gross Domestic Product. A coastal issue is a national issue.
Whatever happens with sea level rise, our coastline is the area most vulnerable to any changes that occur and in ways many don’t consider. In fact, for many communities dealing with sea level rise along the beachfront may be the simplest task ahead. If you work for wider beaches, higher dunes and structures built higher and stronger, and most of your beachfront sea level rise challenges will be handled.
As for the rest of these challenges, let’s encourage more scientific research to define and perhaps resolve the problems listed above and any others bound to crop up. These issues strike at the core of coastal resiliency, the effort to make communities better able to anticipate and adapt, respond and recover to whatever coastal catastrophe comes next. These also are issues that can occur even if sea level rise isn’t a driving force: potable water and habitat preservation are scarce commodities in the best of times, and keeping our economies and our infrastructure healthy and prepared for the future are always priorities.
The prospect of sea level rise, at whatever magnitude, just provides us with even more impetus to act.
Ken and Kate Gooderham
Managing directors, American Shore and Beach Preservation Association