page_title: Check dam
section_title: Materials
hierarchical_section_title: Check dam / Design considerations / Materials
caption_attribution_description: English: log dam building in Adawro
context_page_description: A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, they are an ancient technique dating from the second century A.D. Check dams are typically, though not always, implemented in a system of several dams situated at regular intervals across the area of interest.
context_section_description: Check dams are made of a variety of materials. Because they are typically used as temporary structures, they are often made of cheap and accessible materials such as rocks, gravel, logs, hay bales, and sandbags. Of these, logs and rock check dams are usually permanent or semi-permanent; and the sandbag check dam is implemented primarily for temporary purposes. Also, there are check dams that are constructed with rockfill or wooden boards. These dams are usually implemented only in small, open channels that drain 10 acres (0.04 km²) or less; and usually do not exceed 2 ft (0.61 m) high. Woven-wire can be used to construct check dams in order to hold fine material in a gully. They are typically utilized in environments where the gully has a moderate slope (less than 10%), small drainage area, and in regions where flood flows do not typically carry large rocks or boulders. In nearly all instances, erosion control blankets, which are biodegradable open-weave blankets, are used in conjunction with check dams. These blankets help enforce vegetation growth on the slopes, shorelines and ditch bottoms.
caption: Log dam building in Adawro
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