Slope Drains (Tightlines)
Slope drains in this website are solid wall pipes which carry collected water down a steep slope gradient without exposing the slope face to soil saturation and channel erosion. These drains are usually combined with some energy dissipating structure at the discharge point such as a rip rap pad (apron) or manhole.
Hard to support pipe along vertical bluff faces. May require special anchoring and flow energy dissipation along length. Erosion gullies can start along pipe trenches if not properly compacted and stabilized.
Conveyance system does not place water on the slope. Good steep slope technique.
Piping is commonly undersized. If failures occur the effects on slope stability and erosion control can be rapid and serious. Without proper energy dissipation such as manholes and rip rap aprons at the slope toe, the discharges cause erosion at the slope toe and beach.
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