The 12 per cent deficiency in the southwest monsoon rainfalls during 2014 (June-September) have started impacting India’s water level in major reservoirs.
Data compiled by the Central Water Commission (CWC) show 15 per cent decline in water storage by January 1, 2015 across all 85 important reservoirs of the country.
The CWC estimates total water storage at 89.947 billion cubic meters (BCM) as of the beginning of 2015 which works out to 58 per cent of total storage capacity of these reservoirs.
The storage, however, indicates only 85 per cent of the storage of the corresponding period last year but is equal to the storage of average of last ten years. The Indian Meteorological Department (IMD) reported at 88 per cent of monsoon rainfalls during 2014.
The lower level of storage may impact availability of water for potable, irrigation and power generation purposes in the ensuing peak demand season this summer.
The CWC said 85 reservoirs include 37 having hydropower benefit with installed capacity of more than 60 MW. The total storage capacity of these reservoirs is 155.046 BCM which is about 61 per cent of the storage capacity of 253.388 BCM which is estimated to have been created in the country.
In the western region including Gujarat and Maharashtra, the existing 22 reservoirs having total live storage capacity of 24.54 BCM is filled with just 59 per cent. In volume term, total water storage in the western region reservoirs stood at s 14.48 BCM. By January 1, 2014, however, these reservoirs were filled with 75 per cent of their accumulative capacity.
The current storage is even lower than the last 10 years’ average of 66 per cent. Thus, storage during current year is less than the storage of last year and also less than the average storage of last ten years.
The existing 30 reservoirs in the Southern region with states like Andhra Pradesh, Karnataka, Kerala and Tamil Nadu have an accumulative storage capacity of 51.37 BCM. Of which accumulative water storage currently stands at 24.35 BCM representing only 47 per cent.
The storage during corresponding period of last year was 56 per cent and average storage of last ten years during corresponding period was 61 per cent of storage capacity of these reservoirs. Thus, storage during current year is less than the corresponding period of last year and also less than the average storage of last ten years during the corresponding period.
There are six reservoirs with an accumulated storage capacity of 18.01 BCM in the northern region covering the states like Himachal Pradesh, Punjab and Rajasthan.
The total storage available in these reservoirs is 8.88 BCM which is 49 per cent. The storage during corresponding period of last year was 63 per cent and average storage of last ten years during corresponding period was 54 per cent of storage capacity of these reservoirs, the CWC said.
Both eastern and central regions also witnessed a sharp decline in their accumulated water storage. While the eastern region with an accumulated storage capacity of 18.83 BCM, total water stocks was available at 13.61 BCM or 72 per cent of overall capacity by January 1. Around the same time, however, these reservoirs were filled with 86 per cent of the capacity.
Similarly, the central region covering the states like Uttar Pradesh, Uttarakhand, Madhya Pradesh and Chhattisgarh possesses 12 reservoirs having a total storage capacity of 42.30 BCM. The total storage available in these reservoirs is 28.64 BCM representing 68 per cent of storage capacity as against 74 per cent of reservoirs was filled by January 1, 2014.
