Why filters are provided in dam?

The impervious fill material can act asa barrier to the seepage flow through the body of embankment dam. The inclined or vertical filters abutting downstream face of the impervious core are provided to collect seepage water to keep the downstream shell relatively dry.

What is a dam filter?

Filters are designed and constructed to achieve specific goals such as preventing internal soil movement and controlling drainage, and are typically installed during new dam construction. Filters have also been added to existing dams to meet specific requirements.

Where do filters are placed in a dam?

The filter/drainage zone should be located within the embankment or the foundation such that the seepage flow in high permeability zones or in cracks or other openings will encounter the filter/drainage zone (see Fig. 6).

What is inverted filter in dam?

Inverted filter. The inverted filter consists of one or more layers of graded coarse-grained, free-draining material over less pervious soil. It is used to prevent dams from failing by water piping through the foundation.

How can we reduce seepage in dams?

Control at points of seepage exit can be accomplished after construction by installation of toe drains, relief wells, or inverted filters. Weep holes and relief drains can be installed to relieve water pressure or drain seepage from behind or beneath concrete structures.

How can we prevent earthen dam failure?

The waves developed near the top water surface due to the Winds, try to notch-out the soil from the upstream face and may even, sometimes, cause the slip of the upstream slope. Upstream stone pitching or riprap should, therefore, be provided to avoid such failures.

Do dams have filters?

Do Dams Need Filters? All modern embankment dams (including tailings dams) should have engineered filters and drains to prevent seepage-related failures. Many embankment dams in the United States do not have properly designed filters.

What is phreatic line in earth dam?

The top flow line of a saturated soil mass below which seepage takes place, is called the Phreatic line. Hydrostatic pressure acts below the phreatic line whereas atmospheric pressure exists above the phreatic line. For an earthen dam, the phreatic line approximately assumes the shape of a parabola.

What is the purpose of a toe drain?

The purpose of the toe drain is to collect water seepage in the earthen dam and safely convey it to the pond outfall (8” toe drain outlet pipes can be seen on either side of the large rectangular spillway pipes in the photo below). Toe drains perform an important function in maintaining a safe and secure dam.

What is rock toe in earth dam?

Rock-toe. It is a zone of free draining material consisting of cobble size material provided at the downstream toe of an earth dam. The principal function of a rock-toe is to facilitate drainage of water and protect the lower part of the downstream slope Page 6 from tail water erosion.

Why is seepage important under a dam?

All dams have some seepage as the impounded water seeks paths of least resistance through the dam and its foundation. Seepage becomes a concern when it carries sediments (silt particles) with it, and so, should be controlled to prevent erosion of the embankment or foundation or damage to concrete structures.

How long will an earthen dam last?

50 years
The average lifespan of a dam is often estimated to be 50 years.

What are the disadvantages of barrier-based filtration?

In applications with low levels of contamination, barrier filters can represent good value. The main disadvantages of barrier-based filtration are: Replacement and disposal costs. When this type of filter becomes blocked by waste particles, it needs to be replaced.

What are the advantages and disadvantages of FIR filters?

Advantages of FIR filters : 1 Large storage requirements 2 Can not simulate prototype analog filter 3 For the implementation of FIR filter complex computational techniques are required 4 It is hard to implementation than IIR 5 Expensive due to large order 6 Require more memory 7 Time-consuming process More

Do the advantages of carbon water filters outweigh the disadvantages?

It is clearly evident that the advantages of using a carbon water filter far outweigh the disadvantages. As such, installing such a filtering system is highly recommended if you want to protect your family from any unpleasant contaminants in your water, while keeping expenses to a minimum.

What is the importance of dam in flood control?

During flood season, the flow of water in the downstream can be controlled by a dam. The reduction of the flood will save the crops and property from being washed away. It also reduces congestion of runoff in plains and coastal lands. Avoiding flood hazards can ensure the sustained economy of the whole country.