@coachbryanhoward Hi can you explain how lowering channels leads to erosion? I thought filling in a channel would allow an area for water. I’d like to understand how best ways to manage the site in a scenario for site questions. I put the question below.
The owner provides a topographic survey of the greenfield site of a new shopping mall. The architect noted the site has several steep vegetated hills.
What site strategies should be put in place to mitigate erosion? Check the three that apply.
Revegetate and mulch exposed areas
Correct. Added vegetation and mulch help to hold disturbed soil in place and limit erosion from runoff.
Design development to fit the site and the terrain
Correct. Situating the building on an area of the site with flat terrain will limit disturbance of existing soils, which leads to a greater chance of erosion.
Protect and retain existing vegetation
Correct. Existing vegetation is already established on the hillside and helps prevent erosion from rainwater.
Grade the site by filling in channels
Incorrect. Filling in channels will lower natural flow capacity, causing them to receive larger amounts of water in shorter periods of time, will lead to erosion.
Clear trees and shrubs from hilltops
Incorrect. A lack of windbreaks (trees, shrubs, etc.) allows the wind to put soil particles into motion for greater distances, thus increasing soil erosion.
Strip topsoil from steep hills
Incorrect. The loss of topsoil creates major site damage. The onsite loss of this upper layer of soil nearly eliminates the soil’s natural ability to provide nutrients, regulate water flow, and combat pests and disease.
Reference: Site Planning and Design Handbook