Bengaluru, Jul 2 (IANS):  For the first time in many years, Karnataka is facing water shortage due to deficit pre-monsoon, delay in the onset of southwest monsoon and uneven spread of rainfall across the state, a senior official said on Tuesday.

"Around 37 per cent overall deficit in pre-monsoon showers from March to May, 10-day delay in the arrival of the southwest monsoon and Vayu cyclone disrupting rains have dried up water sources in lakes, tanks, ponds and wells across the state for drinking, irrigation and livestock," senior metrological scientist C.N. Prabhu told IANS here.

Unlike last year, when the southern state had an overall 6 per cent deficit monsoon from June to September, Prabhu said the prospects of making up for the 23 per cent rain deficit in June depended on cloud formations, moisture content and wind movement over the next three months.

"Failure of pre-monsoon showers, delay in the arrival of monsoon and extended summer over the last four weeks have affected the water bodies, reducing water levels in rivers, reservoirs and their catchment areas. Water supply in towns and cities has also been affected," lamented Prabhu.

As per the Indian Meteorological Department (IMD) data, the state received 167mm of rainfall against 216 mm normal, resulting in a 23 per cent deficit.

The coastal area, where the monsoon enters the state from Kerala and the Arabia Sea, recorded 32 per cent deficit with 645 mm rain against 946 mm normal.

In contrast, the north interior region had 3 per cent more (118mm) rain than 114 mm normal.

In south interior region, including Malnad, the deficit was 28 per cent (113 mm) from 157 mm normal.

"Pre-monsoon failure resulted in a record 75 per cent deficit (45 mm) against 179 mm normal in the coastal region, 50 per cent deficit (44 mm) from 85 mm normal in north interior area and 21 per cent deficit (115mm) from 145 mm normal in south interior and Malnad areas," said Prabhu, a weather scientist in the Karnataka State Disaster Management Authority (KSDMA).

As a monsoon dependent state, Karnataka heavily relies on southwest and northeast monsoons for rains to fill its rivers, reservoirs in the catchment areas and dams built across the Cauvery, Tungabhadra and Krishna rivers in its southern, central and northern regions for drinking, hydel power generation, irrigation and livestock across cities, towns and villages.

"A deficit rainfall spells trouble for the 11-million people in Bengaluru, which is mainly dependent on rainfed Cauvery, about 120km southwest from the city," said Prabhu.

With hundreds of lakes and tanks drying up across the city, there is no piped water supply by the state-run water board to one-third of the city, especially in the south east and north east, forcing people to depend on tankers and borewells for water supply.