How do you mitigate debris flow?

You can’t stop or change the path of a debris flow. However, you may be able to protect your property from floodwaters or mud by use of sandbags, retaining walls or k-rails (Jersey barriers). In mud and debris flow areas, consider building channels or deflection walls to try to direct the flow around buildings.

What is a debris flow track?

Debris flows are fast-moving landslides that are particularly dangerous to life and property because they move quickly, destroy objects in their paths, and often strike without warning. Debris flows generally occur during periods of intense rainfall or rapid snowmelt and usually start on hillsides or mountains.

What happens during a debris flow?

Debris flows are geological phenomena in which water-laden masses of soil and fragmented rock rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form thick, muddy deposits on valley floors.

What is the best long term solution to avoiding a debris flow?

Gabions and Reno Mattresses are used on slopes to prevent the formation of debris flows and control them if they occur. Similar to watercourse dams, gabion constructions serve as long-term solutions to control mud flows.

What triggers debris flows?

Debris flows can be triggered in a number of ways. Typically, they result from sudden rainfall, where water begins to wash material from a slope, or when water removed material from a freshly burned stretch of land. Another major cause of debris flows is the erosion of steams and riverbanks.

What is the difference between a debris slide and a debris flow?

Debris flows differ from slides because they are made up of “loose” particles that move independently within the flow. A slide is a coherent block of material that “slides” over a failure surface. Debris flows have larger particles – at least 50% of a debris flow is made up of sand-size or larger particles.

What are the three types of debris flows?

There are generally three types of creep: (1) seasonal, where movement is within the depth of soil affected by seasonal changes in soil moisture and soil temperature; (2) continuous, where shear stress continuously exceeds the strength of the material; and (3) progressive, where slopes are reaching the point of failure …

How do you recognize an ancient debris flow?

To be considered a debris flow, the moving material must be loose and capable of “flow,” and at least 50% of the material must be sand-size particles or larger. Some debris flows are very fast – these are the ones that attract attention.

What can be done to prevent debris flow?

Hard engineering measures such as solid dams, check dams and barriers along the debris-flow path (Liu et al., 2016; Huebl and Fiebiger, 2005) and debris basins at the exits of depositional areas (Huebl and Fiebiger, 2005;Gems et al., 2014) are usually built, to prevent dangerous debris flows from reaching high-consequence areas.

How are deflection walls used to control debris flow?

Deflection walls are commonly constructed as the last element of a systematic debris flow mitigation measures (Huebl and Fiebiger, 2005), regulating and directing the debris flow towards areas of low consequences, such as the main river channel.

What are the causes of debris flow hazards?

The debris-flow hazards are caused by the dynamic process of initiation, transport or deposition.

How are drainage techniques used in landslide mitigation?

There are various drainage techniques that help in the slope stabilization process. A smooth topography of the slide surface can prevent surface water from ponding or connecting with the groundwater. Depressions of the slope might cater to the standing water, which in turn can lead to debris flow.