Test: Considerations of Groundwater - Civil Engineering (CE) MCQ

As a storage reservoir, the aquifer behaviour is controlled by- the nature of the rock and its porosity, structural disposition, with regard to the recharge points or places, climate conditions like annual precipitation.

The importance of groundwater in water supply system can hardly be over emphasized. It is in no way subordinate to that of surface waters.

An aquifer may be made to serve as a filter plant when artificial recharge is made to pass through an intervening layer of rock, which acts as a natural filter.

The position of the water table and hydrogeological qualities of rocks forming foundations and abutments of dams and reservoirs must be known.

An associated trouble with rising water-table is the development of salinity of the soils. The rising groundwater may be rich in some undesirable salts that are left at or near the surface during its loss to atmosphere due to evaporation.

It must be remembered that an aquifer can hold water only temporarily, as the water is always in a state of flow in it. However, the rate of flow of water through an aquifer is very slow compared to surface waters.

The quantity of water that can be withdrawn annually and also the rate at which the withdrawal could be made without adversely affecting the inventory of the aquifer, therefore, determine what may be called operational yield.

A dam is built across a river primarily to store water in the form of a reservoir. The whole idea of a dam would become irrelevant if the foundations on which it is built are made of porous rocks or if a stretch of a reservoir rock is permeable.

Groundwater is a major source of trouble for the stability of slopes. Many slope failures, especially in hilly regions are due to direct or indirect involvement of groundwater.

The root system of crops in water-logged areas gets decomposed. Large areas of land in Indian subcontinent are affected by water-logging.