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Competency Area 3: Drainage and irrigation AEM

PO 21. Understand the concept of hydric soils, hydric soil indicators, and the regulatory, aspects associated with wetlands and the installation of drainage systems.

Hydric soils are defined as soils formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part.  The hydric soil indicators may vary by region and for organic or sandy soils as opposed to loam and clay soils, but they generally must include observations of pronounced organic matter accumulation since plant decomposition is slower under saturated conditions.  Mottled soils near the surface and color hue are key indicators also. The very poorly drained and poorly drained soil drainage classifications usually fit the hydric soil delineation.  The wetland protection rule requires permits be secured prior to draining and altering a delineated wetland.