[[File:Stormwater Tree Trench high permeability native subsoil with structural soil medium.png|thumb|right|400px|'''Tree Trench with High Permeability Subsoil''' - This tree trench configuration possess high permeability soil ([[Soil groups]] A or B), and as a result possesses a clean-out stand pipe/clean-out for the underdrain, which is placed higher in the feature as water will infiltrate through the system much quicker. This allows for further infiltration into the system into the underlying native soil below. Once water has percolated through the soil to the perforated underdrain it is then transported out of the feature and back into the storm sewer system. This configuration also includes a monitoring well to monitor water level in the feature below the aggregate line at the bottom of the feature. This feature contains structural soil, similar to the configuration on the left.]] | [[File:Stormwater Tree Trench high permeability native subsoil with structural soil medium.png|thumb|right|400px|'''Tree Trench with High Permeability Subsoil''' - This tree trench configuration possess high permeability soil ([[Soil groups]] A or B), and as a result possesses a clean-out stand pipe/clean-out for the underdrain, which is placed higher in the feature as water will infiltrate through the system much quicker. This allows for further infiltration into the system into the underlying native soil below. Once water has percolated through the soil to the perforated underdrain it is then transported out of the feature and back into the storm sewer system. This configuration also includes a monitoring well to monitor water level in the feature below the aggregate line at the bottom of the feature. This feature contains structural soil, similar to the configuration on the left.]] |