Mumbai University > Civil Engineering > Sem 7 > Irrigation Engineering

Marks: 5M

Year: Dec 2015

Canal lining is the process of reducing seepage loss of irrigation water by adding an impermeable layer to the edges of the canal. Canal lining is necessary to minimize the seepage losses in canal and to increase the discharge in canal section by increasing the velocity. It also prevents erosion of bed and side due to high velocities.

Advantages of canal lining are: -

1. The lining of canals prevents seepage loss and thus more area can be irrigated by the water so saved.
2. The lining of canal is an important anti-water logging measure as it reduces seepage to the adjoining land.
3. The lining provides a smooth surface. The rugosity coefficient, therefore, decrease. The resistance to flow also decreases and hence the velocity of flow in the lined canal increases.
4. The increased velocity minimizes the losses due to evaporation.
5. The increased velocity helps in provide a narrow cross-section for lined channels.
6. Higher velocity helps in providing a flatter hydraulic gradient or bed slope.