Author Topic: More Sentimental Slop !  (Read 91 times)

Michael Caswell

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Spotted this on the S Carolina site

https://scdhec.gov/sites/default/files/Library/CR-012078.pdf

Did you know trees are detrimental to the structural integrity of a dam? During significant or even moderate wind events, trees can topple over and leave holes and voids in the dam that can lead to an uncontrolled release of impounded water.
 
Roots can extend significant distances into the dam, allowing water to travel along their path; this situation is called piping, and it can occur without inclement weather events whether the roots are healthy or not. Diseased or dead roots become a larger problem as they decompose. Toppling of trees can create a catastrophic failure. Piping generally starts slow and increases with time, but the voids left by fallen trees increase the rate at which water is able to escape. These situations can potentially cause the dam to fail and impact homes, roads, and other property downstream.

Trees can also create shade on a dam, which hinders the ability to have sustained grass cover. Bare areas are vulnerable to erosion during rain events and are especially dangerous if the dam over tops. It is recommended that trees and brush be removed from the entire dam, including both slopes, the crest, 15 feet or half the height of the dam (whichever is greater) past the toe, and the emergency/auxiliary spillway. Spillways should be kept clear at all times to prevent restrictions on the flow of water.

DHEC recommends removing tree saplings as soon as they appear; a permit is not required to remove trees less than 4 inches in diameter. Generally, trees larger than 4 inches in diameter also require removal of the stump and roots. Because stump removal can affect the structural integrity of the dam, a permit to remove the trees and stumps through a tree management plan created by a South Carolina licensed professional engineer is needed.

If you have any questions regarding the need for a permit, please call John McCain at 803-898-8178 or email us at response@dhec.sc.gov.
« Last Edit: March 17, 2022, 11:09:10 am by Doug K »