NBRO has introduced a cleaning device for cleaning horizontal drains and increase their efficiency and slope stability

Lateral gravity drains are used as a structural mitigation measure to reduce slope instabilities by  lowering ground water level and thereby increasing factor of safety and the stability.

Efficiency and capacity of a lateral gravity drains could be complete or partially blocked by (i) mechanical clogging with fine sediments, (ii) chemical and biochemical clogging with iron oxides or (iii)  by algae, moss and plant roots overgrowth, which ultimately lead to significant decrease in the rate of groundwater outflow.

If these blocks are not cleaned properly, the groundwater level in the slope could increase and lead to an unforeseen instability of a protected slope or a landslides. Therefore proper cleaning practice should be followed to maintain a slope stability.

NBRO has introduced a cleaning device to clean horizontal drains and increase their efficiency to prevent a slope instability or a landslide. This method has successfully applied to the mitigated landslide in Garandi Ella and have shown positive results in cleaning the lateral gravity drains.

Click here to view technical document