Potential dam safety problems, such as misalignment, cracks, animal burrows, surface erosion, seepage, slipping, sloughing, etc., can be spotted early enough to take corrective action. Mowing should precede each dam inspection. Although woody vegetation such as trees and brush may protect against surface erosion, such growth can cause other, serious problems. These problems may develop over years and may go undetected until too late. In addition, trees or brush can hide an embankment surface making inspection difficult.
Trees eventually die, and their roots decay and rot.
The root cavity leaves a void within the dam through which water can leak and lead to a piping failure. In addition, a tree can be blown over during a severe storm and create a large hole in the dam caused by the uprooted root ball. Because tree root problems occur over a long time, even decades, they often go undetected. Control of trees on dams - Trees should never be allowed to grow on a dam. Any tree on a dam should be removed, its roots grubbed out and instead appropriate low growing vegetation established.