Presently there are evidences in India indicating the real occurrence of impact from climate change scenario. Drought in Bihar , extreme daily rainfall in UP, Mumbai, and the Nilgris, and again floods in UP, Haryana and Delhi , danger level crossing of flood water in Yamuna river were some worth mentioning examples for such impact that were noticed during South west monsoon of 2010 in India.
All along in the past, it is observed that there was either delay in onset or early withdrawal of monsoon rainfall in India. But during 2010, there was overlapping between withdrawal of south west monsoon rainfall and onset of north east monsoon rainfall in India against the normal onset of north east monsoon rainfall by 20th October with ± one STD from the mean. Further the withdrawal of north east monsoon prolonged beyond January, 2011 during cold weather period and it gives speculation that something is happened in the atmosphere. Because of accumulation of green house gases in the atmosphere, the atmosphere is presently under confusion and this is universal, since there is no political boundary for atmosphere.
This type of confusion persists permanently aggressively; it would affect the annual water availability of India, which is presently 400 Mham. This will trigger the existing surface water conflict between different States of India still further.
The understanding drawn from the above statements reveal that every water molecule received from a single rain drop must be conserved for future use and also the available existing water molecules must be rationally used in order to keep the sustainability of food security, though there is no head and tail for hydrological cycle. I feel that the average per capita water availability in India will decline < 2000 CUm³ in the coming years.
Water is used in India for three purposes in a major way. viz., 85 per cent for agriculture and the remaining 15 per cent for domestic and industries requirements.
Population gets increased to 121 crores as per latest census(2011) and this would add pressure on drinking water requirement further and this additional quantity must be diverted from agriculture. Further existing and new industries may also require more water for their industrial increased production and also to treat their effluents to keep environment clean. This activity also would demand more water and this share also must come from agriculture. Both domestic and industrial water demand put together would be around 25 per cent (5 and20 percent respectively for domestic and industry). This will reduce water availability to agriculture to 60 per cent.
Under this context the water problem to agriculture must be well addressed in order to provide food security to every Indian citizen through the following strategies;
- Water budgeting and crop planning must be carried out at village level by the community themselves with external support from extension side
- Popularization of Systems of Rice Intensification(SRI) for irrigated rice
- Encouraging aerobic rice, where SRI is not possible to execute
- Establishing water bank at village level(enhancing water availability and efficient use of water)
- All dry land areas must be brought under watershed development
- Renovation water body structures at village level
- On-farm testing of irrigation at critical stages of crop growth of food crops and recommendation based on the results obtained to the users
- Popularization of best practices identified from community for the economic use of water for irrigation and extrapolation to akin areas.
- River linking in different phases—Intra state, inter states, between south India, between North India, between west India, between east India and within in India