Area	Anderson Creek
Topic	Tour: Restoration Tebbutt's Massive Vegetated Hard Points 1997-98

 

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This photo shows the pilot use of large baskets made of high tech plastic material (uniaxal geogrid by Tensar) to act as massive hard points to turn the forces of the river at flood. The plastic this material is "poly" type so it is long lasting in this application, whereas metal would be more subject to breaking by bedload and subject to rust. The baskets can hold 500,000 pounds of mass at a fraction of the cost of rip rap. Structures have been up to 122 feet long, 22 ft wide, and 9 1/2 feet high. Supply of large rock also requires quarries, which can be environmentally destructive. See Pictures #7-8 for structures in action during 1998 flows. Photo by Chris Tebbutt.


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This high water shot in February 1998 shows a gravel filled basket holding its own against the strong current of Anderson Creek at high flow. As the structure catches soil, trees, shrubs and mosses colonize the substrate. Soil builds up behind them and they become part of the river bank. Photo by Chris Tebbutt.


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This photo shows vegetated hard point structures on the property downstream of the Tebbutt, with willow and cottonwood starts embedded in the structures not yet sprouted. The mature hardwood tree behind the structures is a good reference for restoration in this reach. Connie Best and Chris Mann, the land owners, helped with a cost share obtained through the Mendocino County Resource Conservation District. Chris Tebbutt designed and implemented the project. Photo by Chris Tebbutt. 1998.


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Soil trapped during the falling leg of the hydrograph behind rock baskets was planted with willow, alder and cottonwood. This area has since completely filled in with soil deposited by Anderson Creek. Note willow sprigs planted in the fresh deposits. Photo by Chris Tebbutt. 1998.


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This picture shows Anderson Creek looking upstream in spring 1998. Chris Tebbutt is preparing cottonwood and willow poles for deep planting behind his new "vegetated" hard point structures. While the rock baskets look unsightly in this photo, they soon became fully colonized by trees, moss, aquatic plants and other vegetation (see Picture #8). Photo by Stephanie Tebbutt.


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Although the rock filled basket on which Chris Tebbutt is standing is not yet covered with vegetation in this 1997 photo, the mass of the basket has not only protected the bank behind him and trapped soil, but also created scour to form a pool in Anderson Creek. Photo by Pat Higgins.


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Alder sprouts are already obscuring the large rock basket on the toe of which Chris Tebbutt is standing in this period of moderately high water in 1999. Photo by Stephanie Tebbutt.


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As baskets trap soil and seeds from aquatic and riparian plants during high water, vegetation starts to sprout. For final results see the next Tour for 2003 photos. Photo by Chris Tebbutt.

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