Riser Pipes

riser pipe post fire

 

What – Riser pipes function to sieve debris and allow passage of water.  Riser pipe allows accumulation of bedload sediments released from a drainage due to the loss of soil cover and reduced infiltration from water repellant soils.  The sediment and ash captured in the basin can be removed with a backhoe.

Purpose – Risers are used to protect road infrastructure, especially those with large fill, from failure.  Riser pipes help prevent culverts from plugging with sediment and floating debris.  Pipes capture sediment and reduce downstream impacts to water quality.  Riser pipes also reduce peak flows by storing water and sediment.

Effectiveness – No formal effectiveness monitoring data exists for risers.  However, reports indicate risers performed well when maintained.  Problems occurred when structures were not routinely checked and debris was not removed from the basin.  Risers are temporary treatments that are easily disassembled when no longer needed.  Risers are installed quickly and at a low cost.

Where

  • Access at road crossings with a culvert inlet is limited by conventional equipment (backhoe).
  • Drainages with high-burn severity and erosion predictions indicate a high risk of sediment delivery.
  • Channels that have high bedload transport capabilities.

Cost – $750–1400 for labor and material.  Additional factors include:

  • Location and access
  • Culvert size and inlet condition

How to Link – See USDA BAER Catalog page 140 (PDF 148).