What is Hydrogeology?

Hydrogeology (hydro- meaning water, and -geology meaning the study of the Earth) is the area of geology that deals with the distribution and movement of groundwater in the soil and rocks of the Earth’s crust (commonly in aquifers). The terms groundwater hydrology, geohydrology, and hydrogeology are often used interchangeably.

Groundwater engineering, another name for hydrogeology, is a branch of engineering which is concerned with groundwater movement and design of wells, pumps, and drains.[1] The main concerns in groundwater engineering include groundwater contamination, conservation of supplies, and water quality.[2]

Wells are constructed for use in developing nations, as well as for use in developed nations in places which are not connected to a city water system. Wells must be designed and maintained to uphold the integrity of the aquifer, and to prevent contaminants from reaching the groundwater. Controversy arises in the use of groundwater when its usage impacts surface water systems, or when human activity threatens the integrity of the local aquifer system.

What then is Hydrogeological Survey?
A hydrogeological survey is an investigation of the hydrologic and geologic parameters at the subsurface level in a particular area.

Hydrogeological maps may be formulated with the data gathered during such a study. It involves the detailed evaluation of the water-bearing levels of rocks and their capability for filtration. Moreover, the intrinsic ability of these rocks to either store or resist water is also assessed. The pressure, type and quality of the underground water is noted, delving into the intensity of the water flow through pores or fractures.

A hydrogeological survey is done to determine the underground water level. Hydrogeological surveying is conducted prior to drilling a borewell in order to ascertain water availability at a particular location. It has been well established that underground water is a better source of drinking water than surface water. This is due to the following reasons:

Lower chances of pollution, especially if it is at least twenty meters away from the sanitary work.
Water becomes naturally purified as it flows through sand and stone.

Borewells remain shut and therefore have a reduced chance of contamination.
Water temperature at the underground level is always at desirable levels in spite of seasonal changes.

Greater chances of water availability in summer as the water sources are situated at a deeper level.