What are check dams and its applicability

Check dams

Check dams are small, temporary structures built across a drainage channel or watercourse to slow down the flow of water, reduce erosion, and promote sediment deposition. They are commonly used in various environmental and engineering applications to manage runoff, control soil erosion, restore degraded landscapes, and improve water quality.

 

A water body would be established behind the check dam at the start of construction, and the water body would gradually be filled by sediment deposit. Because grain production is essential in that region, the area formed by the deposit is utilized as farmland.

Applicability of Check Dams

 Where temporary or permanent channels are not yet vegetated, channel lining is not possible, and velocity checks are required, check dams can be employed. This approach can be used to reduce erosion in small open channels as a temporary or emergency treatment. This method should be utilized on drainage areas of less than 2 acres. Check dams can be utilized in the following situations:

 

●       Reduce the flow in small temporary channels that are now degrading.

●       Because of the transient nature of the problem, permanent stabilization is not possible.

●       Construction delays or weather circumstances prohibit the timely placement of non-erosive liners in minor eroding channels.

Advantages of Check Dams

●       It's inexpensive and simple to set up.

●       Reduce the water's velocity and maybe promote aeration.

●       Check dams to minimize gully erosion before vegetation has a chance to grow, as well as for settling out a large percentage of the sediment load in the runoff.

●       These check dams can sometimes be left as permanent installations with just minor regrading, etc. if they are appropriately positioned and planned.

●       They can be used as spillways, with deposited material graded and seeded, or as check dams, capturing sediment flowing away from the site.

Disadvantages of Check Dams

●       Many of these measures are unsightly due to their temporary nature, and they should be removed or converted to permanent check dams before homes are rented or sold.

●       Depending on the type of check dam installed, removal may be costly.

●       Check dams can only be used in a small drainage basin.

●       If the water level remains high after rainstorms or if there is extensive sedimentation, grass linings in channels may be killed.

●       Reduce the channel's hydraulic capacity.

●       Turbulence may occur, causing the channel banks to disintegrate.

●       In the fall, leaf clogging might be an issue.

Planning considerations for check dams

●       Stone check dams are the most common type. The center must be lower than the edges.

●       The dams should be spaced so that the toe of the upstream dam and the top of the downstream dam are at the same elevation.

●       Ensure that overflow sections along the channel are resistant to erosion induced by check dams' out-of-bank flow.

●       Check dams can also be made out of logs or sandbags filled with pea gravel. Log check dams may be more cost-effective in terms of material prices, as logs are frequently reclaimed during clearing operations. Installing log check dams, on the other hand, takes more time and manual labor. In most cases, check dam stones must be purchased.