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Organization
editI 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.
Proposed restructuring of page and new material
editBelow 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. [1]. 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. [2].
Function
editA 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.[3] 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.[4]
Uses
editPrimary Applications
editCheck dams are used primarily to control water velocity, conserve soil, and improve land.[5] They are used when other flow-control practices, such as lining the channel or creating bioswales is impractical.[6] 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.[7] 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. [8].
Arid Regions
editIn 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.[9]
Mountainous Area
editAs 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.[10]
Design Considerations
editSite
editBefore installing a check dam, careful inspection of the site must be undergone. The drainage area should be ten acres or less. [11]. The waterway should be on a slope of no more than 50% and should have a minimum depth to bedrock of 2 ft. [12]. 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.[13].
Materials
editCheck 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.Cite error: A <ref> tag is missing the closing </ref> (see the help page).Cite error: A <ref> tag is missing the closing </ref> (see the help page).. They may kill grass linings in channels if water stays high or sediment load is great. This criteria induces a weir effectCite error: A <ref> tag is missing the closing </ref> (see the help page)..
Type
editMaintenance
editReferences
edit- ^ Mayhew, S.(2009). check dam. In A Dictionary of Geography. : Oxford University Press. Retrieved 4 Oct. 2014, from http://www.oxfordreference.com.libproxy.usc.edu/view/10.1093/acref/9780199231805.001.0001/acref-9780199231805-e-3395.
- ^ http://water.epa.gov/polwaste/npdes/swbmp/Menu-of-BMP-Background.cfm
- ^ http://www.iowasudas.org/manuals/design/Chapter07/7E-7.pdf
- ^ http://books.google.com/books?id=oFMO9nOiBKwC&pg=PA140&lpg=PA140&dq=check dams flow velocity&source=bl&ots=Prgw82M1Tv&sig=fYC8JVRvz3UkPxTVFRYe8yQXcGQ&hl=en&sa=X&ei=qHcxVJaUKM2zogSNiYKIBg&ved=0CDkQ6AEwBTgU#v=onepage&q=check dams flow velocity&f=false
- ^ A conceptual model of check dam hydraulics for gully control:efficiency, optimal spacing and relation with step-pools C. Castillo, R. Pérez, and J. A. Gómez from Hydrology and Earth System Sciences 18, 1705–1721, 2014
- ^ http://water.epa.gov/polwaste/npdes/swbmp/Check-Dams.cfm
- ^ http://portal.ncdenr.org/c/document_library/get_file?uuid=efbff6bd-e595-4828-be6a-394be4c404c2&groupId=38334
- ^ http://www.udfcd.org/downloads/pdf/critmanual/Volume 3 PDFs/chapter 7 fact sheets/EC-12 Check Dam.pdf
- ^ S. Parimala Renganayaki, L. Elango (April 2013). "A REVIEW ON MANAGED AQUIFER RECHARGE BY CHECK DAMS: A CASE STUDY NEAR CHENNAI, INDIA". : International Journal of Research in Engineering and Technology 2 (4): 416–423
- ^ Mazzorana, Bruno (6 June 2014). "The susceptibility of consolidation check dams as a key factor for maintenance planning". Österreichische Wasser- und Abfallwirtschaft. 66 (5): 214. Retrieved 5 October 2014.
{{cite journal}}: More than one of|pages=and|page=specified (help) - ^ http://opcgis.deq.state.ms.us/Erosion_Stormwater_Manual_2ndEd/Volume1/Chap_4_Sections/4_4/V1_Chap4_4_Runoff_Conveyance_CD.pdf
- ^ http://www.deq.idaho.gov/media/617590-32.pdf
- ^ http://www.deq.idaho.gov/media/617590-32.pdf
Martinodesign (talk) 15:58, 20 October 2014 (UTC)
- Martinodesign, I will read this over more extensively later. My first thoughts are them being "...constructed across a waterway". Swales and bioswales, which check dam cross, aren't necessarily waterways as they can be dry much of the time. Also, "...such as lining the channel or creating bioswales is impractical." Should this be "...creating additional bioswales..."? It already looks better than what is there now. Thanks for putting this together.--NortyNort (Holla) 21:23, 20 October 2014 (UTC)
- You are right, I updated and edited what I posted a bit more. If you want to check out the edited version, look here. Feedback would be appreciated! Look forward to working on this further. Martinodesign (talk) 02:22, 5 November 2014 (UTC)
Beaver Dam Analogues
editAre Beaver Dam Analogues a type of check dams? Palnatoke (talk) 19:40, 25 December 2020 (UTC)