CWC's original assessment of water availability 'reliable'

New Delhi, Apr 11 (UNI) The original Central Water Commission's (CWC) assessment of availability and requirement of water in 1993 -- both surface and sub-surface levels -- at 1869 billion cubic metres (BCM) has been found 'reliable' by a standing committee of the Ministry of Water Resources.

There was some confusion about the authenticity of this figure arrived at by the CWC when the National Commission for Integrated Water Resources Development Plan (NCIWRDP) in 1999 differed slightly with the CWC assessment for two reasons.

Firstly, because in Brahmaputra sub-basin the additional contribution of flow of nine tributaries joining the downstream of Joghibhopa site was included, while in Krishna basin the estimation based on the mean flow of yield series was accepted by the Krishna Water Disputes Tribunal Award, sources said.

Stating that a proper assessment of availability of water -- both surface and underground -- should be made for enabling the country to make a proper planning, development and managing of this scarce resource. The water precipitation in the form of rain and snowfall was crucial component of hydrological cycle making available the fresh water on a renewable basis.

The geographical area in India was 329 million hectares with a mean annual rainfall of 1170 mm with an annual precipitation of of about 4000 cubic KM. A significant part of this precipitation seeps into the ground and the balance flows through streams and rivers and collects in the waterbodies adding to the surface flow.

Part of the water that seeps into ground remains as soil moisture in the upper layers of the crest added to ground water source.

However, a major part of water from the surface flows and soil moisture and groundwater resources when put into various uses returns to atmosphere through evapo-transpiration, sources explained.

Following the NCIWRDP's different assessment in 1999 a standing Sub-Committee of the Ministry of Water Resources for assessment of availability and requirement of water for diverse uses in the country after a detailed study had acepted that the CWC's original assesment was 'reliable', sources said.

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