NEW DELHI : Even after over a month of the arrival of the southwest monsoon, the overall water storage position in major reservoirs across the country is less than that of the corresponding period of last year.

The storage at 150 reservoirs is 39.72 billion cubic metre (BCM), which is below normal as that marks 22% of their total capacity, according to the latest bulletin of the Central Water Commission.

The normal storage level is calculated as the average of last 10 years’ data. Last year the storage available in these reservoirs for the corresponding period was 50.42 BCM against normal of 44.06 BCM.

The storage levels in reservoirs of all regions are below last year’s and normal levels. Some states, such as Andhra Pradesh and Bihar, have reported huge deficits in storage (-76%) while a few others like Uttarakhand have recorded surplus water (+48%) in their reservoirs, the CWC bulletin shows.

The lower water level would impact irrigation of crops in Cauvery basin where the Karnataka government has not released stipulated water and Tamil Nadu reservoirs have recorded -40% deficit in storage.

Experts say the water storage level would improve in the coming days as the monsoon system regains strength. So far, the country received an overall deficit rainfall in June by -11%. The northwest region received the highest deficit rainfall (-32.6%) last month. The current year’s normal monsoon is important to fill the huge gap created in reservoir levels due to last year’s deficit monsoon.

The region-wise analysis shows that reservoirs in eastern and southern regions are closer to the last year’s water level whereas those in the northern, western and central regions are facing a big gap.

The northern region data shows the total live storage available in these reservoirs is 5.39 BCM, which is 27% of their total capacity. The storage during corresponding period of last year was 45% and normal storage was 31% of capacity of these reservoirs, according to the bulletin.

In western region, the latest bulletin shows , the total live storage available in these reservoirs is 7.94 BCM which is 21% of their capacity levels. The storage during corresponding period of last year was 27% and normal storage during corresponding period was 22% of live storage capacity of these reservoirs.

Moreover, in the central region, the total live storage available in the reservoirs is 12.25 BCM, which is 25% of their total live storage capacity. The storage during corresponding period of last year was 35% and normal storage during corresponding period was 26% of live storage capacity of these reservoirs.

However, in the eastern and southern regions, the total live storage is close to corresponding period of last year. The current live storage level is 19% in the eastern region while last year it was 20%. In the southern region, the current live storage is 19.03% that is quite close to corresponding period of last year, which was 19.43%. Moreover, there is a sizable gap in comparison to normal storage level.

Pradip Kushwaha, an independent meteorologist tracking the monsoon, said, “Monsoon Intrapersonal Oscillations (MISO) are gaining strength and this will likely to trigger good rainfall over the coastal Karnataka, Kerala, Maharashtra, and Tamil Nadu during July 9-13. Besides, some heavy spells are likely over west coast of India.”