GUWAHATI: For the flash flood prone Guwahati that has already faced water logging issues in the last two showers of pre-monsoon rain, the Indian Meteorological Department’s (IMD) forecast of a lesser intense monsoon this time than last year, has come as relief to the district administration.
According to the long range forecast of IMD, region wise, rainfall is likely to be lesser (93 per cent of Long Period Average of rainfall) in the northeast while the rest of the country – 100 per cent LPA over northwest India, 99 per cent LPA over central India and 95 per cent LPA over the south peninsula.
“The rainfall might be 8 per cent higher or lesser than the forecast. This is much lesser than last year. Last year, the northeast had a rainfall of more than 97 per cent LPA and had a variation rate of 19 per cent as opposed to this year’s 8 per cent. So, the monsoon is expected to be drier than before this time,” Sanjay O’Neil Shaw, director of Regional Meteorological Centre (RMC), the Borjhar-based IMD office, told G Plus.
According to the met department, the southwest monsoon has arrived in the northeast region on June 1 and chances of rainfall are imminent in the next 48 hours.
“Southwest monsoon has further advanced into some more parts of the northeast, Bay of Bengal and some parts of Mizoram and Manipur. The Northern Limit of Monsoon (NLM) passes through Shirali, Hassan, Mysuru, Kodaikanal, Tuticorin, into Aizwal of Mizoram and Chura Chandpur of Manipur. Rains have already started in those areas and conditions are favourable for further advance of Southwest Monsoon into some more parts of northeast states including Guwahati in Assam during the next 48 hours,” Shaw said.
The city had lost at least seven lives last year during the monsoon season due to various cases of electrocution and flash floods.
In the last two weeks, the city received quite a few showers of rainfalls that lasted more than 4-6 hours from which several places of the city got inundated for more than an hour.
According to the met department, these rains have been due to the combination of many weather systems persisting across the region. The first system is the cyclonic circulation which is prevailing over sub Himalayan West Bengal and adjoining regions. The other system is a trough which is extending across West Bengal up to Manipur. Moreover, southerly humid winds from Bay of Bengal are also feeding moisture over northeast India which is resulting in good pre-monsoon activities over northeast India.
But as far as the south-west monsoon that reaches this region from Arabian Sea is concerned, northeast is going to have a rather sunny than a cloudy monsoon.
Incomplete projects a stumbling block for flash flood free Guwahati
Though the GMDA has this year completed the first phase of a Rs 26 crore worth drain to divert the storm water from the flash flood prone areas to Bharalu River and channel it into the Brahmaputra, one cannot but ask about the old projects that were proposed earlier by the same department and yet remained pending.
To mitigate the storm water flowing down from the Jyotinagar Hill catchment area starting from Bamunimaidum to Sunsali Hill including the Guwahati Refinery complex, flooding the Zoo Road area and other low lying areas such as Anil Nagar, Nabin Nagar etc, the GMDA built a 1,700 metre long drain connecting Bamunimaidum to Noonmati.
“Pumps have been installed to divert water through this Noonmati drainage system. The project cost is Rs 26 crores (approx) for Phase – I. The total length of the drain already constructed is 1,700 metres. The width of the drain is 6 metres and the depth varies from 3 metres to 5.50 metres which is enough to carry the load of the storm water. The drain has been constructed with RCC framed structure as per requirement of the railway department as it is constructed on railway land. The pump capacity is 4,000 litres per second which is likely to be increased in due course. This will bring down the flash flood in those areas by 25 per cent,” Dhiren Baruah, GMDA chairperson said.
However, there are three other projects, announced last year that remain to see the light of the day.
For the storm water coming down from Meghalaya, the GMDA had taken up building a second alternative channel for flood water into the Basistha River. The department was also supposed to build a sewage treatment plant on Bahini River so that the drains don’t get clogged and had decided to set up seal tape on the Bharalu River at Sarabhatti. These projects are expected to be completed within last year.
Every year during the rainy season, the city reels under flash floods in several areas such as Anil Nagar, Tarun Nagar, Rajgarh, Birubari, Khanapara, Dhirenpara, Shantipur and several other regions of the city.
Apart from causing inconveniences, flash floods and waterlogging have also resulted in injuries and casualties. So far, the flood waters were channelled through only two rivers in the city – Bharalu and Bahini River – by using pumps that while giving momentary relief, often used to get overloaded during heavy rainfall.
“The detailed project report for the channel that will be built within the Assam border to divert Meghalaya water has been sanctioned by the chief minister and works had also started. But, due to lack of funds, it has hit a momentary limbo,” Baruah said.
Regarding the sewage treatment plant, S Venkatesan, managing director of Guwahati Metropolitan Water & Sewage Board that is looking over the completion of the project said, “We are having problem in allocating lands to set up the treatment plant.”
