Talk:Check dam

Organization
I think this page is a great introduction to check dams. However, I believe that the page is hard to follow and subsequently needs to be reorganized.

Possible suggestions include sections on: Introduction, Functional properties of check dams, Applicable uses of check dams, design of check dams, and examples of existing check dams with appropriate links.

I hope to work on breaking the current information on the page into such categories and further expanding on them.

Martinodesign (talk) 22:35, 7 September 2014 (UTC)

Proposed restructuring of page and new material
Below is what I have been working on over the course of the last month or so. I pulled some of the information that was already on the page and tried to restructure it. I then did some additional research to flush out some parts. It is still in the works but I was hoping to get some feedback from all those that are interested.

A check dam is a small, often temporary, dam constructed across a waterway to counteract erosion by reducing water flow velocity. . They are considered one of the EPA's Best Management Practices to address the physical aspects related to urban runoff, such as erosion and scour. .

Function
A check dam placed in the ditch or channel interrupts the flow of water and flattens the gradient of the channel, thereby reducing the velocity. Although some sedimentation may result behind the dam, check dams do not function as sediment trapping devices. Second, they can be used not only to slow flow velocity, but to distribute flows across a swale to avoid preferential paths and geared toward vegetation.

Primary Applications
Check dams are used primarily to control water velocity, conserve soil, and improve land. They are used when other flow-control practices, such as lining the channel or creating bioswales is impractical. Accordingly, they are commonly used in degrading temporary channels, in which permanent stabilization is impractical and infeasible in terms of resource allocation and funding due to the short life period. Or, they are used when construction delays and weather conditions prevent timely installation of other erosion control practices. This is typically seen during the construction process of large scale, permanent dams or erosion control. As such, check dams will serve as temporary grade control facilities along waterways until final stabilization is established or along permanent swales that need protection prior to installation of a non-erodible lining. .

Arid Regions
In arid areas, check dams are often built to increase groundwater recharge in rural areas in a process called managed aquifer recharge. Winter runoff thus can be stored in aquifers, from which the water can be withdrawn during the dry season for irrigation, livestock watering and drinking water supply.

Mountainous Area
As a strategy to stabilize mountain streams, the construction of check dams has a long tradition in many mountain regions dating back to the 19th century in Europe. Traditionally, mountain communities built permanent structures in the upper part of the catchments to to protect against natural hazards, targeted at decreasing both the magnitude and frequency of events, and supplemented by afforestation of the valley slopes to reduce erosion and to prevent triggering events. Land-use, such as residential developments, in the run-out areas of hazardous processes increased since the 1950s, and a considerable amount of values was concentrated in endangered areas. Such consolidation check dams, built in staircase-like sequences and targeted at preventing bed incision and stabilizing adjacent hill slopes, are widespread in Alpine streams and still are used nowadays to mitigate flood and debris flow hazards. To give an example, approximately 30,000 check dams have been constructed in the Province of Bolzano-South Tyrol, Italy, since 1900, and 16 % of them were judged not to fulfill the required reliability and, consequently, technical efficiency requirements.

Site
Before installing a check dam, careful inspection of the site must be undergone. The drainage area should be ten acres or less. . The waterway should be on a slope of no more than 50% and should have a minimum depth to bedrock of 2 ft. .  Check dams are often used in natural or constructed channels or swales. They should never be placed in live streams unless approved by appropriate local, state and/or federal authorities. .

Materials
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, logs or sandbags..

Size
A check dam should not be more than 2-3 feet high,  and the center of the dam should be at least six-inches lower than its edges. . They may kill grass linings in channels if water stays high or sediment load is great. This criteria induces a weir effect, resulting in increased water surface level upstream for some, if not all flow conditions. .

Beaver Dam Analogues
Are Beaver Dam Analogues a type of check dams? Palnatoke (talk) 19:40, 25 December 2020 (UTC)