Swale question for poorly drained soil in Pennsylvania
Location: Beaver County, Pennsylvania (~ zone 6)
posted 4 years ago
Say there's a 4% sloped plain to be converted to food forest. It's 150 feet by 150 feet. There's fragipan of glacial till 3' thick that's 6-8" below the topsoil. We get 42" of rain throughout the year. In the spring there is too much water for young trees and their roots rot. This summer we had a drought for 2 months. The idea is to make swales on contour that will drain water in the spring and hold water in the summer. There's a central path over a pipeline perpendicular to the contour and the swales we are thinking will come off of the central path in a dendritic pattern. The swales would then let extra water drain through the central path, but hold water up to the level of the central path. We would then plant trees in the berms, focusing on trees that don't mind wet roots (American Persimmon, Cornelian Cherry.) How far apart would you make the swales (we're thinking about 20')? How deep and wide? Where would you put the paths? On the bottom of the swale or right before the swale downhill of the berm?
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