‘Rain water need to be analysed before recharging ground water’

Speaking at a national-level seminar on ‘rain water harvesting and artificial recharge to ground water with special reference to Coastal areas,’ organised jointly by the Central Ground Water Board and Geoinformatics division of Mangalore University here on Thursday, he said “though we have been speaking of rain water harvesting, quality of rain water is not been given emphasis so far. Till recently, rain water was considered pure. However, the studies have shown that even rain water from the roof is contaminated with heavy metals, discharges from industries, horticulture chemicals, materials used for roofing, paints. Rain water must go through series of process before it is used for recharging the ground water.”

He said “urban population will be 5 billion by 2025. Though rain water harvesting is not a permanent solution for conserving water, it will certainly solve water crisis for sometimes.
Water bodies are filled for reclamation in urban areas. Concrete structures obstruct natural percolation of water. This has resulted in artificial floods in cities which were unheard of in the past. As the stagnant rain water can be recharged into the ground, suitable rain water harvesting structures should be installed as a measure of flood mitigation. Storm water drains can be connected to nearby open wells/recharge pits and in nearby parks.”

There is a need to catch the rain to recharge the ground water, he added.
Central Ground Water Board Regional Director T M Hunse said “the rapid pace of development and the increase in population led to the exploitation of water resources, resulting in the overuse of surface supplies and over exploitation of ground water.

Dependence on ground water to meet the needs of domestic and industrial sectors resulted in lowering ground water level. As a consequence, wells are getting dried. Hence, it is essential to take up measures to conserve and augment the renewable natural ground water resources,” he added.

Mangalore University in charge Vice Chancellor Prof K K Achary said water can not be reproduced in laboratory in large scale.

Government has implemented various programmes making rain water harvesting mandatory in buildings in metropolitan cities. The rain water harvesting must be made as a people’s movement so that people regulate the usage of water. The university can also think of rain water harvesting methods, he added.

Registrar Prof Chinappa Gowda released digital abstract volume comprising the technical papers presented during the seminar.