The Hindu 22.10.2010
Water levels in Vizag district depleting
Ramesh Susarla
Composite hydrograph of Visakhapatnam district that shows a decline in groundwater level during the past five years.
VISAKHAPATNAM: Groundwater levels in Visakhapatnam district have been falling in the past one decade under extreme stress due to indiscriminate exploitation of this resource in the absence of surface water availability.
A study done by the Department of Ground Water in the past five years on average groundwater levels recorded through aquifer peizometers at 42 observation wells — dug one in each mandal, shows the levels turning from shallow to deep.
In-charge Groundwater Deputy Director R. Krishnamurthy Raju told The Hindu that during current monsoon season, the rise in water levels from May had been encouraging and the district average rose by 3.15 metres compared to September 2009 and by 3.86 metres compared to May this year. All this was possible due to 29.01 per cent excess rainfall during the current year till September-end in Visakhapatnam district. Against a normal cumulative rainfall of 712.89 mm for the season, it received 919.71 mm and in September alone against a normal rainfall of 190.01 mm the rainfall was 226.40 mm recording 19.15 per cent excess.
Eleven mandals of Agency area recorded an excess cumulative rainfall of 37.8 per cent, and 57.2 per cent during September alone.
The other two revenue divisions (Visakhapatnam and Narsipatnam) of the district also received about 25 per cent of excess rainfall during the season. Study results show that during October 2005 water was available at a depth of 3.13 metres from surface, but that had dropped to 4.45 metres now. When compared to 2009 water year, the lowest water level in May had come up 9.5 metres against 10.1 metres, and the highest level reached in 2009 was 6.58 metres in October against this year’s 4.45 metres in September.
Dispelling all doubts of sea water ingression into city drinking water aquifers, he said thanks to the hard rock formation along the major part of coast and excellent gradient towards sea, no major problem was foreseen.
