Mad River Bluffs Stabilization
In 2008 a road, several homes, and utilities were threatened by the encroaching Mad River within the Mad River Estuary. This project that was designed and constructed by BioEngineering Associates, Inc. successfully stabilized 1,300 feet of 23 to 40 foot high vertical eroding bank within the estuary. This project included the use of Live Willow Brush Layers, Coir Wrapped Soil and River Run Gravel Lifts, Boulder Wing Deflectors and Redwood Log Habitat Structures. During this project the river estuary was protected from sediment intrusion by the use of a unique floating curtain that adjusted to the eight foot rise and fall of the tide.
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| The Mad River just before it reaches the ocean. 1300 ft. of 23-40 ft. high eroding vertical bank threatening homes and the road in. | To begin we built a road from the meadow down to the toe of the vertical bank. It was 25 to 30 feet wide in order to stabilize the bank and recapture land that had been lost to the river. Although we used large boulders at the base of our structure, the bulk of the fill was river run gravel that had been previously mined from gravel bars just upriver. |
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| We had to get our base rock and gravel layer above high tide before we could place the willow layers, as the willow would not tolerate the salt water. | A dense mass of live willow branches are laid on a coir-wrapped soil layer. |
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| The branches are covered with local river run gravel. | The next layer of soil is brought in and will be wrapped in coir, a coconut fiber net and blanket that is strong, long lasting and bio-degradable. |
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| Looking downstream during construction. In the fore ground, one of the Boulder Wing Deflectors separating the 60 to 80 foot long Coir and Willow Lifts. | Returning to the site in March 2009, Spring’s new growth had begun. |
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| Well established willow has stabilized the bluffs. | |
Video
This 5 minute, time lapse video, set to music, presents a quick glimpse of BioEngineering Associates, Inc.'s project to stabilize 1,300 feet of erodoing bluffs in the Mad River Estuary where a road, homes, and utilities were threatened by the encroaching river.