Saturday, April 9, 2011

Water Problems, Flooding and Erosion visible everywhere on Whidbey Island

On Whidbey Island, s narrow strip of sand about 50 miles long in the Puget Sound, giant forests used to shade the ground allowing for the slow decomposition of giant logs by smaller plants and mosses, all of which used and absorbed water, ultimately protecting our soils from erosion. There was no runoff in a forest-covered land, with the plant roots acting as anchors and the mosses the sponge.

Architect Joe Green in Alpine Lakes Wilderness

Some of the trees would wash down to the sea and become driftwood. Huge logs interlocked in a semi-fluid crystalline structure that could move and give with the forces of storms, but that ultimately protected our island's edges from erosion from high seas.

dbBrad Hankins infront of one of the few remaining old growth trees in WA.  This one is in the Alpine Lakes Wilderness.
It is a shame that all our first growth trees on Whidbey Island were harvested in the early 1900's to supply fuel for steam ships. I can't image standing on a spring board 6' off the ground and spending all day cutting down just one of those big trees.  Or how long it may have taken to cut rounds and split them up into tiny pieces suitibaly for burning.  Or how beautiful the lumber cut from such a tree might have been. But it happened and there are few big trees left.  As much as I love beautiful lumber, I feel the few old growth trees we have must remain standing for all future generations to enjoy as a tree, in a forest.  It will be one thousand years before we have any more such trees.

Land worked over by tractors.  No forest, no stumps, no native plants, just grass that won't quite grow, and lots of water running down the hill.

But we have replanted, and little trees grew up to become medium trees.  Before they could become big trees, most were logged again in the 70's and '80's. But this time theree was heavy equipment to pull all the stumps, eliminate the understory and reshape the land to make it flat and buildable.  The compaction and removal of forests literally destroyed the lands ability to absorb water and resist erosion.

Wetlands are a very important ecological component of water retention. They store, clean and slowly release the water.
So what we have now are baby forests with small trees and no understory full of invasive species and not really healthy forests, wetlands with fill and development, lots of impermeable surfaces like driveways, planter strips, roads, houses and lawns and beaches and bluffs with no substantial driftwood protecting them.



Trees, stumps, understory, forest duff, mosses, and virtually all habitat removed to build a house in the woods!
Elsewhere along the perimeter of South Whidbey Island is a windy road called Wilkinson.  Wilkinson Road has been closed for years now because of erosion problems. One end of Wilkinson has been renamed Zimmerman and the other end has been closed to traffic and is a bike path.  There is lots of water collecting in the forest above this steep sandy bank and where there is healthy forest there is no errosion.  But where there are houses above, there is errosion.  Here is an equatin I just wrote to mathematically sumarize our water issues.
A large slide on Whidbey Island, a result of poor wter management above.  Courtesy of Department of Ecology.


Forest = Storm Water Control
Houses + Driveways = Errosion.

A million dollar blunder on Chuckanut Bay in Bellingham.  See how they deal with the water--a big black pipe to the sea.

Below pictures are an example of what water un-absorbed and running without obstacles can do. And, in case you think ivy is good for erosion control, I'm pretty sure you see ivy vines in the following pictures. Slides happen right under the ivy because as the depth of the ivy builds up the roots are no longer touching the ground, providing little to no erosion protection.

Wilkinson Road Closed to traffic on one end.  Errosion slides like this are evident all around whidbey island
I've been down to this beach several times.  The road is a stream when it's raining and a marsh that seeps water most of the year.  It crosses 3 different draingae paths (streams). Interesting that most of the errosion is happening where houses or storm water is being collected and discharged above.

The slide totally filled over the road and nearly knocked the bulkhead over.
Tight lines on our bluffs are a mistake.  They're ugly for one, but the real problem is longevity.  I've been building for 30 years and I've seen some crazy details for pipes in comercial buildings for area separations, fire and earthquake movement, but there is no way to affordably construct a pipe down a steep fragile bluff 150, make it look good, do no damage during installation, and provide for 100 years of service.  How long do we think these houses and roads will be around, anyhow?

The Large woody debris on the beach is the only thing keeping portions of the bluff from just washing away.  If the county would stop encourageing people collect and dump their water over the edge but rather insist property owners  provide for retention, storage, habitat and re-absorbtion, our bluffs would at least have a chance.
Dealing with the water from above and giving it a place to go where we can have habitat and retention and even some purification but most importatnly where we can encourage it's slow absorption back into the aquafers and keep it from running fast and eroding our fragile bluffs.  This is the answer.

There used to be a road behind this wall, now it's a water feature.
 This is just my opinion though, certainly not the current approach of island county development.  During my last walk I met a man who was aware of the errosion problems but he had a different take on how to solve the problem.  "The trees" he said, "are the problem.  If we cut down all the trees and covered the banks with plastic" he suggested, we could solve the problem on our bluffs.  Oh goody.  If we want to go this route, I suggest we rethiung the Langley Marina because no one is going to want to approach Whidbey Island from  the water, that's for sure!

The trees are the solution.  The big evergreens have mostly been cut, the madronas are dying, the weedy alders have a high root stress to heigt ration meaning they create more stress on the bluffs than stability, and the understory quite often is mostly invasives like ivy and blackberrys which grow over the natives but provide little absorbtion and bank stabalization.  The trees, the big trees is what we need back on our bluffs. 
 

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