Raja’s crops were scorched due to the prevailing extreme dry weather conditions. A farmer in Dharmapuram, Kilinochchi, Raja complained that they had no rain for many weeks. “All our produce is going to waste because of the lack of water,” he said.
Farmers in the Wanni complain of a double blow as water supply from the Iranamadu tank had been halted due to repair. “Things will get very bad if this situation continues,” warned Raja.
Sri Lanka receives 60 per cent of rain from the Southwestern monsoon from May to September and the second inter-monsoonal rains during October and November. “In fact, we get 30 per cent, one third of Sri Lanka’s total rainfall from the second inter-monsoonal rains. This is a considerable amount of rain, considering the fact that it is within just two months,” said Meteorology Department, Deputy Director, Anusha Warnasuriya.
“That’s the major difference between this year and last year. In 2016 we didn’t receive the October-November inter-monsoonal rains.”
Unlike the first inter-monsoon season during March and April, depressions and cyclones in the Bay of Bengal results in strong winds leading to thunderstorm-type of rains, particularly during the evenings. The whole island receives rains in excess of 400 mm.
The Indian Ocean Dipole (IOD), otherwise known as the Indian Niño, is fluctuation of sea-surface temperatures in which the western Indian Ocean becomes alternately warmer and then colder than the eastern western Indian Ocean. During the negative phase of the IOD waters warm and greater precipitation in the eastern Indian Ocean and cooler and drier conditions in the west is observed. To make a long story short there has been a noted lack of thundershowers that result in rain for Sri Lanka. To make matters worse, Warnasuriya explained that the winds that fed the cyclones in the Bay of Bengal during October and November a dry wind resulted in less rain.
“Generally Sri Lanka doesn’t receive rain during January and February,” said Warnasuriya.
But rest assured rains can be expected in the days to come especially after January 24, according to Warnasuriya.
But Sri Lanka will not experience adequate rainfall until the next monsoon, which is in March. Deputy Director of the Disaster Management Centre for Jaffna, Sangarappillai Ravi said that the district could lose out on its entire crop cultivation if they do not receive rains by end of January.
Speaking to Weekend Nation on the impact of the drought situation in the North, Ravi said that the farmers needed 1400 mm of rain a year for cultivation. However, he pointed out that Jaffna lacked the necessary system to harvest rainfall. “Last year we had a rainfall of 392 mm in one day. But most of it flowed into the sea. This is because we do not have a rain harvesting system,” he said.
He also said that 14 out of the 15 DS divisions in Jaffna had been reported as drought-affected this time. “It was never like this. There are four divisions which are annually affected by drought. They are, Karainagar, Velanai, Oorkavalthurai and Nedunthivu. However this time the situation is so severe that we were able to provide water only to Karainagar,” Ravi said.
Accordingly, a proposal has been put forward at last week’s District Development meeting to address the situation by introducing effective water harvesting systems at every home. “We have urged the authorities to incorporate a proper rain water harvest mechanism when they approve a house to be built,” he added.
Meanwhile, the Urban Development Authority and the Ministry of Environment recently introduced a new green ratings system on January 9 for the purpose of promoting the construction of green buildings with minimal harm to the environment and for the continuous maintenance of them as green buildings.
Based on the guidelines issued in the ratings system, it has been mandatory that all future State, Government and semi-Government buildings obtain the required green certification. All future constructions are to be given marks out of 10 for the water efficiency factor of the buildings.
Final certification will be given based on a mark out of 100, of which the category of water efficiency is just one component. In considering the aspect of water efficiency in buildings, constructions will receive marks for the provision of rainwater harvesting, waste water recycling, the efficient use of waste water, water metering, system for identifying water leaks and the necessary tools and equipment.
Of the expected economic benefits, the reduction of the operation cost, the improvement of employee productivity and worker satisfaction, and the increase in the value of the buildings are envisioned alongside environmental benefits such as the decrease in the use of fresh water.
Senior Lecturer at the Department of Civil Engineering of the University of Moratuwa, Dr. Rangika U. Halwathura called for the use of potable water for gardening, flushing toilets and cleaning vehicles to be reduced.
The National Water Supply and Drainage Board explained that planning on the part of top level policymakers with regard to ensuring the provision of drinking water during droughts was extremely poor.
A Chief Engineer at the Board, Dr. SK Weragoda, who specializes in water treatment including used water treatment, said that policy planners had not taken the issue of this critical factor seriously despite expecting the drought which is the result of a multitude of factors including natural alarms like global climate change. It must be noted that options to be applied and practised for ensuring the provision of drinking water in the wet zone do not work for the dry zone.
With regard to addressing the issue in the wet zone, the construction of salinity barriers to prevent saltwater intrusion should be prioritized along with the establishment of dedicated man-made drinking water storages, in upstream, upper catchment areas such as Maha Oya or Kelani and the reservoir in Kalutara. Again in the wet zone, the proper safeguard of forests in hilly areas too must be done as nature retains water. The reservoirs in Castlereagh and Maussakele cannot be used for this end as they are used by the Ceylon Electricity Board for hydropower generation.
The dry zone has a system of small scale and medium scale scattered lakes and reservoirs. Of the options available in this regard in the dry zone, a proper groundwater management system with groundwater banks and barriers to secure them by preventing pollution being set up are required, prior to which the total volume of groundwater available must be explored, quantified and proper places identified. Surface groundwater including shallow groundwater can be used for day to day affairs other than for purposes of drinking and cooking.
Furthermore, in the dry zone, rainwater harvesting must be done at an individual household level. Also, in the dry zone, the option of using sea water via the construction of a couple of desalination plants in locations such as those in Trincomalee, Mannar, Hambantota and the Jaffna peninsula, for extracting water through the process of reverse osmosis must be considered.
“Although conducting a proper hydrology research study based on weather modeling, an aspect regarding which China is keen to help the country put in place a satellite based weather prediction model, is of utmost importance, high level Governmental policymakers had not shown much interest”, Dr Weragoda explained.
He bemoaned the lack of a national water policy. As contingency for a worst case scenario, in a few pocket areas like Aranayake and Mawanella – one should not have a water treatment plant (for drinking water) in the area as it is landslide prone – bottled water storages should be put in place – as Japan does in earthquake prone areas – to supply the minimum usage of a particular affected area. All of these applications and practices are utilized in natural disaster hit countries such as Australia and New Zealand.
“To ensure the availability of drinking water in the wet zone, we depend on key rivers including those in the coastal zones, which we must identify. These include the Maha Oya, Kelani, Kalu, Walawe and Nilwala.
Downstream to upstream, how many salinity barriers are there where the gates can be closed during the dry season? Weragoda maintained that a proper plan is required and should have been done at least 10 years back. He pointed out that catchment areas have not been improved.
“There must be a sustainable solution. We need capacity building in terms of infrastructure construction to tackle weather type natural disasters. We don’t have the resources to manage,” Weragoda elaborated.
Policy initiatives not based on data
Referring to the Irrigation Department’s plans to build 1,235 agro-wells and the 400 new wells to be constructed by the Water Resources Board, Senior Lecturer at the Department of Geography of the University of Colombo, Dr. Ranjana UK Piyadasa said that the move was not only unwise but also unethical.
“The government’s decision to dig the wells is not based on data. The authorities have no idea about the groundwater availability,” said Piyadasa.
He pointed out that digging more wells will exacerbate the situation by increasing the pressure on a resource already under stress due to lack of rain. Piyadasa said that there are approximately 25,000 dug wells in the dry zone. “This is an estimate. Nobody knows the exact number, no one has done an inventory of the wells in these areas,” said Piyadasa, reiterating that it is unwise to make such a policy decision without even knowing the number of wells in the dry zone.
“The agro wells are large diameter shallow wells that will tap shallow ground water. They will pump out water every single day.”
Piyadasa explained that once a groundwater aquifer is depleted it will take time to replenish. “Both vegetation and biodiversity will be affected and these will take time to cooperate”, he said.
As for the tube wells, Piyadasa said that they could also affect water availability of other privately owned wells. “Tube wells tap deep seated aquifers and may affect groundwater resources and may even deplete it. But there is no way of telling without a study.”
“Besides, we have no idea about the water quality,” said Piyadasa.
He pointed out that these being agriculture areas, agrochemical use is very high. “The water maybe contaminated with high levels of heavy metals. In fact, high levels of fluoride has been detected from some of these area”, Piyadasa revealed. He also pointed out that there is a high incidence of kidney disease in these areas, hypothesized to have been caused by heavy metals.
Irrigation Department, Director General, Engineer SSL Weerasinghe, refuted the claim that the proposed 1,235 agro wells will adversely affect the groundwater table. “These are shallow wells and are scattered in a large area. The estimated impact is a one to two foot drop in the groundwater table”, he said. This premise is based on the fact that 1000 wells were dug last year which resulted in a six-inch to one foot drop in the ground water level, according to Weerasinghe.
The proposed wells are to be built in Anuradhapura (725), Hambantota (150), Kurunegala (225), and Puttalam (135). “Which makes up 1,235 wells in total. Add to this the 1000 existing wells in Urulewa, North Central province, the total number of agro wells are 2235,” revealed Weerasinghe. In addition 1000 minor tanks will also be restored.
He said that these wells, with a diameter of 12 metres and a maximum depth of 20 feet are built on request by farmers and if after the dry spell the wells are no longer required they can be closed up. The project is estimated to cost around Rs 40 million.
When asked whether the department was aware of the number of agro wells in the area and their potential impact on groundwater resources, Weerasinghe said that there are many privately owned agro wells the numbers of which the department does not keep tab.
“But this is inconsequential as the proposed wells are to supply water to paddy fields and the privately owned ones are used in vegetable cultivation areas.”
The Water Resources Board (WRB) has commenced rehabilitating tube wells (1242 wells identified as high yielding which can pump 1000 litres to 3000 litres a minute in terms of volume as a counter-measure to address the drought situation, and a further 400 new wells are to be constructed by the NWSDB in areas identified as likely to be affected by the drought. Chairman of the WRB, ACM Zulficar pointed out that they had been carrying out studies about the groundwater levels and other related areas since 1966 and with the data gathered would be advising the NWSDB from where to extract the water and how. “Our only request to the public is to use water sparingly at all times,” he pleaded.