I wonder how effective the EZ Drain is if the backfill is made with native, somewhat
impervious soil.
Eight sites were selected for
impervious soil samples, including four road sites, and two each from residential paved squares and alleys.
of packed impervious soil to help prevent water from seeping behind the wall.
There's no impervious soil, so the water heads south, slowly waterlogging and increasing the weight of the soil packed behind the wall.
Changes in soil properties (e.g., burn areas from wildfires), hydrophobic or
impervious soils, removal of surface vegetation, and excess runoff from warm rainfall on significant snowpack can also be important contributors.
if runoff occurs quickly because of saturated soils,
impervious soils, or intense rainfall, then herbicide runoff from conservation tillage fields could be greater.