The next day at the workshop, we went into the field at Las Cienegas Conservation Area to restore streams that were downcutting through the fields. This area used to be used for catttle grazing. Our first project was to create a zuni bowl at the headcut of a stream. We dug out the area of the bowl, then lined it with fabric. The fabric collects fine sediments that are needed for vegetation to grow. We placed a couple layers of rocks down, with the largest rocks at the bottom. We also built up the sides of the bowl with rock so they did not collapse. With so many people, we were able to build the structures fairly quickly. The structures and materials are simple and the techniques can be easily transferred to other places.
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| Zuni bowl with a one rock dam below it |
After the zuni bowl was completed, we built a one rock dam blow it. The dam is only one rock high, and should be about 1/3 the height of bank flow. While the zuni bowl helps to slow down the water from the head cut, it also raises the level of the stream bed creating a steeper slope downstream. This may cause the velcoity of the water to increase leading to more erosiosn. The one rock dam raises the level of the bed downstream to slow the flow down. When water flows, sediment will pack around the rocks.
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| Finishing the Zuni bowl. |
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Building a zuni bowl
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