Storm Surges & Tsunamis: Why Coastal Wetlands Matter
March 11, 2011 § Leave a Comment
Let’s say you stay inside and watch tv all day, hate nature, and don’t have an issue with concrete rivers. You are unmoved by pleas to think of ecosystems and all the other life forms out there.
Well, you probably wouldn’t be reading this blog.
But for the many millions of Americans who think like that, now is the teachable moment. Consider the terrifying images seen by so many of us of the tsunami sweeping buildings across Japanese coastal lowlands. Anyone remembering the storm surges of Katrina?
I am reminded of the Tsunami Hazard Zone signs posted around Venice and Playa del Rey, that little blue circle that says, here’s the line between being swept by the sea and safety.
That tsunami zone correlates with historical wetlands, now filled and populated, much like those coastal towns on television right now.
After similar devastation in 2004 in Indonesia, observations surfaced that the tsunami had the worst effect in areas that had experienced wetland losses via development. Where mangrove forests, a kind of coastal wetland, were intact, the public was buffered and the impact of the waves were lessened. [Related digression, from Wikipedia: "Of the six native tribes only the Nicobarese, who had converted to Christianity and taken up agriculture in place of their previous hunter-gatherer lifestyle, and mainland settlers suffered significant losses. Many of the aboriginal tribes evacuated and suffered fewer casualties.” The other tribes read the signs of the land and knew to head uphill, demonstrating that valuable interplay between the many indigenous worldviews -including spirtualities - and ecosystem knowledge that often gets lost through “modernization” of a people.]
Similar discussions pertaining to Louisiana’s significant loss of both wetlands and barrier islands validate that coastal wetlands are natural hazard protections. It is widely understood that leveeing the Mississippi River is the major cause of degradation of coastal wetlands in the gulf coast. Instead of sediment spreading and rebuilding these wetlands, it shoots out into the Gulf. It’s that sediment transport thing, again.
So I can’t help noticing in one particular bit of footage, the massive waves barreling over fields towards a straightened and lined river channel, carrying urban debris with it, and I understood that I was seeing the parallel condition of our tsunami zone/historical coastal wetlands; a former wetland and flood zone turned to other uses. Who made the decision to build in floodplains, to fill wetlands?
On our side of the Pacific, this is our moment to pause and think hard about our infrastructure decisions. We claim to care about life – so much so that in at least one state we will entertain legislation that applies a presumption of guilt to women with miscarrying pregnancies. Such a woman will have to prove that human agency was not involved. Good luck with that. And yet human agency is front and center when it comes to filling wetlands and straightening streams, and highly provable. So is is it time to presume guilt when cities and counties rubber stamp developer plans that fill wetlands and floodplains, straighten and line streams? For deaths due to bad development decisions are even more preventable than many miscarriages.
What Japan’s, and Indonesia’s, and Louisana’s suffering shows us is that preservation of life is taking a back seat to profits. Protect life by working with natural processes – and something of a mantra here at creekfreak, knowing when to stay out of the way. You can make your money, oodles of it, outside of floodzones and wetlands. But if you bulldoze a coastal wetland, build in a flood zone and sell home sweet home, you just may be selling a very preventable death.
Japan is still reeling – and will be for many days to come. Their coastal infrastructure has taken a serious hit, their nuclear power plants unstable, and aftershocks keep coming. I wish them healing, and an ecosystem approach to rebuilding their coastline.