subsurface drainage/underground outlet

Subsurface Drainage/Underground

Outlet

Contractor Certification

Training

March 2008

Mike Cox, SCE

Purpose: Improve the soil environment for vegetative growth by intercepting and preventing water movement into a wet area.

Subsurface Drainage (606)

Primarily used for drainage of grassed

waterways in Indiana.

Purpose: Dispose of excess surface water without causing damage by flooding or erosion.

Underground Outlet (620)

Primarily used to drain WASCOBs in

Indiana.

Minimum Depth

• 2.0 feet in mineral soils• 2.5 feet in organic soils

Requirements

• No reverse grades• Tolerance-Grade to 0.1 % above• Flatter grades could require the drain size to

increase.• Meet ASTM F-405

– 3 to 6 inch• Meet ASTM F-667

– 8 to 24 inch

Requirements

• Install Animal Guards

Underground Outlet

Installation Report http://www.in.nrcs.usda.gov/technical/engineering/engineering.html

Look Under Contractor Certification Section

Subsurface Drain

Installation Report http://www.in.nrcs.usda.gov/technical/engineering/engineering.html

Look Under Contractor Certification Section

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