Mitigating Droughts in the Dry Zone of Sri Lanka. A Point of view
Posted on August 24th, 2014

Dr Sudath Gunasekara (SLAS) Retired Secretary to Prime Minister Mrs Sirimavo Bandaranaike and President Senior Citizens Movement MAhanuwara. 22. 8. 2014.

It is with much interest I read the article by my friend Ranjit Mulleriyawa in the Island of 8th August
under the caption, ‘Preparing to meet future drought situations’. Though the heading as well as the content of his article looks covering a broader aspect of drought, I think he is specifically talking about the drought in the dry Zone. Nevertheless it is a piece everyone concerned with this subject should read.

My focus in this discussion is on droughts in the Dry Zone and how to mitigate them. However judging by the prolonged drought experienced from Feb to June this year all over the Island, I think droughts in this country have to be looked at from a broader perspective without confining to the DZ. Droughts are of two types, They are natural and manmade. Natural droughts are cyclic and usually occur at long term intervals due to global climatic phenomena (like El-Nino, secular solar fluctuations or other atmospheric disturbances) over which man has very little or no control at all. But manmade ones could be controlled by proper planning and better management of available resources. Collecting maximum rain water in the tanks, economic use of available water, water conservation, improving vegetation cover and exploring possibilities of using millions of gallons of water of those rivers that flows down to the sea unused, could be listed as few examples of such strategies..

Ranjit has identified the following areas as crucial issues in addressing the current problem. Conserving the environment, repairing the irrigation works, conserving and effective utilization of groundwater, sustainable use of groundwater, harvesting and storing rainwater, rainwater harvesting for domestic use and going for conservation farming

Obviously the steps need to be taken immediately as Ranjit suggests are very relevant to address the issue at hand. Since these steps present a mixture of both short term and long term remedies I would prefer a more meaningful ad effective approach to this problem by taking up short term and long term solutions separately in order to find a permanent solution to this national problem. I also envisage a broader approach to this problem.

In Sri Lanka there are two distinct climatic zones namely the Wet Zone ( > 75” annual rain fall) and the Dry Zone (< 75”). Factors such as its location on the globe, its relation to global wind belts, major land masses and oceans, size and shape and the peculiarities of its physiographic characteristics with a peculiar highland at the centre with a coastal lowland around, narrower in the SW and broader in the other parts have mainly influenced this climatic variations. We have a Wet Zone in the SW fed by the SW Monsoons (May to October) with perennial rivers and abundant water but plagued with recurrent floods causing immense misery and hardship to people. Major part of it, just flows down, in to the Indian Ocean, without being used for the benefit of man, though we have inherited a rich legacy of ‘not allowing a drop of rain to flow in to the sea without being used for the benefit of man’, from the days of Parakrmabahu the Great. We have miserably failed to make use of waters of Kaluganga and Kelaniganga that have the first and third highest annual discharges in the country (8183mcm and 5579 mcm respectively), by allowing such precious wealth given by nature to flow down to the ocean, of course except the little electricity we generate.

On the opposite side we have a Dry Zone covering more than two third the total area of the country mainly fed by the NE Monsoon from Dec to March which has no rain almost for eight months of the year. Recurrent droughts today have become routine of the day here. Almost all the rivers flowing down this part of the Island, with the exception of Mahaweli go dry during the dry spell. But this constitutes the rice bowl of the nation that supplies the staple diet of the Islands people.

The lowlands in the SW are frequented with floods and its upper reaches are plagued with earth slips due to heavy rain and deforestation from mid 18th century at higher elevations. These two regions also have evolved two different systems of irrigation systems, a weva and Ela system in the DZ and an Amuna and ela system in the WZ. Ancient people in the DZ built water bodies called Wev in the DZ to collect rain waters and what flows down the rivers during the rainy season. Mahaweli flowing through the NE lowlands and Kaloya in the NW were the only perennial rivers they could tap to augment and sustain some of the tanks in the DZ. The only instance where a Wet Zone stream, was tapped, with the exception of Mahaweli at Minipe, was Pattipola Bhoo Ela Project that tapped the waters of Dambagastalawa oya (a head stream of Kotmala oya), whose waters were diverted to the Uma Oya by a trans-basin canal through a tunnel dug under the Pattipola ridge that was fed by a nine mile canal starting almost at 7000 feet level on the northern slope of Totupola- Kirigalpotta ridge. Other than these two exceptions there is no evidence where our forefathers had made any attempt to divert the waters of any river that has its source in the Wet Zone to the DZ.

The ancient people adopted two strategies to make the maximum use of water so collected in the DZ wev. First, they used direct rain water as much as possible for cultivation during the Maha thereby saving the water in the tanks and made use of the water collected in the tanks mainly for the Yala season, when there was no rain. Perhaps that may be how some of the fields in the DZ were bale o be cultivated three times a year.

Secondly in order to ensure these Tanks store the maximum volume of water, they were regularly de-silted and the irrigation canals and structures were maintained regularly on a communal basis.

As such return to Sri Lanka’s ancient wisdom in water and ecological conservation and management should be the first step and the best approach one could resort to in this regard. May be we need a new Parakramabahu to re-invent that wisdom. Unfortunately the present day political fire fighters do not have such vision or wisdom.

Talking about the droughts in the DZ that covers more than two third the total area of the country and about 16 million people who are said to be affected by the prevailing drought, finding a solution to this national problem I think should be given the highest priority. I have a feeling that it is even more important than defeating the LTTE. Authorities must realize that even their drinking water problem cannot be solved by distributing bottled water or by taking water by bowsers from outside, whenever there is a drought in that part of the country. Imagine what we are going to do suppose it persist for a longer period like what is said to have happened during the Beminitiya saya. How long are we going to provides water by bottles and bowsers and how long are we going to give them drought relief. These are some of the crucial issues one has to seriously address. What we do now could be compared to the proverbial monkey’s story of thinking to putting up an abode for the rain whenever it gets soaked in rain only, during the rainy season.

It is not only drinking water these people need. They also need water for other purposes like agriculture (their mainstay in life), and myriads of other needs like bathing, washing, and upkeep their animals etc. Additionally water is also needed for the survival of the entire life system, both fauna and flora. As there will be no life if there is no water it is also a crisis of saving a civilization. In short today water is a matter of life and death for more than 2/3 of the total population of this part of the country. As such the magnitude of the problem is much more serious than we think. Therefore this subject needs more serious thinking and long term planning. That is why I say this issue needs to be addressed at the highest level with the topmost priority much more seriously than the present practice of resorting to fire fighting practices adopted whenever a drought occurs. Furthermore I feel that this should be treated as one of the most serious and critical national problems we face as a nation. In fact this is the kind of pro-action that should be undertaken by the Ministry of disaster management without indulging in fire fighting.

Even in historical times we have had droughts in the DZ. But they were not frequent and regular like today, though few of them like the Beminitiya Saya (103-89BC) and Ekanilika Saya (187-189 A.D.) had been   long and severe. Sri Lanka then had a better forest cover and the whole world definitely would have been much cleaner as there was no atmospheric pollution like industrial toxic emission.

Today while we have frequent droughts in the DZ there are regular floods in the WZ. In the DZ, unlike in the ancient days now a days the spill gates of the major tanks in the DZ are usually opened with few rains to save the bunds. The same thing happens even in the WZ. This is because either the tanks have no capacity due to heavy silting of their beds or the bunds are not strong enough to withstand the pressure of more water. This results in allowing the precious rain water to go down to the sea unused, which could have been otherwise used for the benefit of man if the tank beds had been de-silted in time and the bunds had been strong enough to withstands the additional pressure. Isn’t this a simple management problem? Who is responsible for this negligence? Where is the Government, where are the multitude of Governors Ministers, Provincial Councils, Pradesiya sabhas and public servants who are suppose to be responsible for the upkeep and maintenance of these structures and delivery of services to the people?

In this backdrop I would suggest the following steps to be taken as mitigatory measures.

Steps that should be taken immediately

1 De-silting all the tanks in the DZ before the onset of the NE monsoons.

2 Repair all irrigation canals, tank bunds and other structures etc at the same time,

(These activities should be carried out annually).

3 Take immediate action where necessary to raise tank bunds and to strengthen them to increase their capacities so that we can store the maximum water from the next NE Monsoons without allowing it to flow down to the sea.

4 Concurrently take action immediately to start an aggressive rain water harvesting programme so that rain water could also be collected in other places other than existing tanks. Eg new tanks and other devises both for domestic and agricultural use.

Long term actions

This programme should be followed by a long term national water and forestry conservation programme for the whole Island with the twin objectives of a) increasing perennial river flow and underground water deposits and b) increasing rain fall and control soil erosion, land degradation and floods

5 In this regard the first and foremost thing to be done is the conservation of watersheds in the central highlands, which I call the ‘Geographical Heartland’ of this Island nation. Restoration of the local forest cover will even improve cloud formation and enhance rainfall. Once this is done all rivers starting in the Central Hills will become perennial and their dry weather flow will also increase substantially. Besides underground water resources will also increase and sustain. That should mitigate occurrence of droughts. This needs the declaration of all lands above 5000 feet msl as strictly conserved forests as it was done during the days of Sinhalese Kings (Thanchikele). The declaration of all lands over 60% slope, crest lines, riparian belts in the hill country and even below 5000 feet, etc also has to follow. This might invariably raise the issue of tea plantations, its adverse effects on the economy, employment of estate labourers etc. But one must at least now realize the magnitude of environmental, climatic and ecological damage that was done by the opening up of plantations on these high lands in addition to the drying up effect it had on all the streams by removing the virgin forest of nearly 600,000 acres in the heartland. This devastation not only destroyed the prime forest cover and water sheds but also the ecological balance on the hill country, and degrading the heartland that sustained the entire life system in the whole country. The only way to restore these age old water resources and the ecological balance is to restore the original forest cover of the central hills at least above 5000 feet.

In this regard we must not forget that almost all our rivers have their sources on the central hill country and it constitute the biggest natural reservoir of the country as it provide the source for all underground sources for our rivers as well. The rivers that start here flow down the hills and the coastal lowlands guarantee and sustain all forms of life and our survival on this Island. As such isn’t it the physical stability of this Hill Country that finally decides the survival of the entire life system in this country in the same way as the beat of the heart decides the fate of a living being?

Eminent men on forestry like FDA Vincent (1882) of the Indian Forestry Commission who was hired by the then Government to prepare a forestry policy for Sri Lanka (the father of modern forestry policy) and Douglus Hooker (1873) also have strongly recommended the conservation of forest lands over 5000 feet in Even the forestry policy approved by the government in 1995 states that all the forest areas are to be managed in a sustainable manner in order to ensure the continued existence of important ecosystems and flow of forest products and services. It also recognizes and respects the traditional rights, cultural values and religious beliefs of people living in and adjacent to forest areas in the Central Hill country, though no one has taken such advice seriously up to date.

According to the Report of the Land Utilization Committee 1968 the area > 5000 ft in the Island is 288 sq miles. Of this 187 square miles are found within the Nuwara Eliya district, Kandy district 47, Badulla dist 38 and Ratnapura and Kegalle 16. There are 120 sq miles > 6000 feet. Of this 94 sq miles are found in Nuwara Eliya. 8000 acres of tea are found on land > 6000 ft msl.

 

Even Sri Henry Beresford Director General of Forestry United Kingdom giving evidence before the Land Utilization Committee has pointed out the need for preserving the forests of land above 5000 feet elevation where virtually all rivers have their origin as a matter of absolute necessity. This will enhance the dry weather flow of all rivers in the Island and also improve the ground water resources he said.

6 These items should be taken up as high priority in the conservation of the Heartland- the central hill country as a national treasure. As such the Central Hill Country of Sri Lanka does not belong to the owners of Tea plantations or the labourers working on them, who came there from South India as daily paid labourers during the late 19th century. No does it belong to few tourist hotel or holiday bungalow owners. It belongs to the entire Sri Lankan nation including those to be born tomorrow as well. Therefore, the need to protect it for the posterity as a national heritage cannot be overemphasized.

7 The Pinus plantations in the hill country are another curse. They also should be replaced with local varieties that are appropriate to local climatic conditions that recover and improve ground water deposits as soon as possible.

8 Meanwhile excessive usage of water for paddy cultivation also has to be controlled. Economize water usages and improve water management in the DZ. Breading rice varieties that require less water and alternative methods of controlling weeds in place of water and introducing crops that need less water than paddy also should be encouraged.

9 Explore the possibilities of diverting excess Kelani waters to NWP and to NCP through Kalaweva .

There was a proposal to divert Kelani Ganga and Maha Oya waters by a trans-basin diversion to the NW Province, the objective of the diversion being partly minimizing flooding of the lower Kelani valley, and partly irrigation in NWP (DSWRP Water Sector Report). Apparently, a detailed study has been done in 1961 on the diversion of Kelani Ganga by a firm of foreign consultants, and this project should be revived immediately in view of the anticipated worsening of the drought situation in the country. After diverting Kelani waters to the NWP, if a part of it could be again diverted to Moragahakanda the downstream supply of Ambanganga could be augmented to provide more water to the NE and the East as welly.

10 Another fete is exploring the possibility of taking Kaluganga waters along the highest contour below the southern Great Wall up to at least to Menikganga upper catchment. A reputed irrigation engineer once told me about a conspiracy done to avoid this and constructing Udawalawe at a lower level than otherwise possible to keep the Sinhala population in the SP under control. Tunnels, open ductsand damscould be devised to get the highest possible contour to construct the canal.

Years ago there was a plan to build a large reservoir by constructing a high dam across, Kukule Ganga with the view to taking water to the South-East along a canal referred to as the South-East Dry Zone (SEDZ) canal, comprising part tunnel and part open duct, and running along the 120 m contour. But this was dropped due to public protest (Engineer G.T. Dharmasena who is a strong supporter of this proposal is reported to be having all the details about this project.)

(We are a nation who never solves a problem in time until it becomes almost intractable. Look at the LTTE terrorism. The Middle East domestic servant’s problem. Problems in the Universities. The 13th Amendment. Proportional Representation system that has made hundreds of electorates MPless and their voters deprived of having a representative in Parliament. The Indian Estate labour problem. Corruption and waste in politics and public service. Now the latest, the drug menace.

I hope and wish the content of this article will also not end up with the same fate.

8 Finally expedite the current proposal to divert water from Gin Ganga and Nilwala Ganga in the South to the South-East early. In the present proposal, reservoirs will be built across Gin Ganga and Nilwala Ganga and after inter-linking them by trans-basin tunnels and canals; water will be taken to the South-East Dry Zone. The reservoir at Gin Ganga is expected to operate a power plant with capacity 49 MW. The diversion is expected to cost Rs. 73 billion (Sunday Weekly on 22.06.2014). It is better to give priority to the proposals than concentrating on Uma oya Project which is very unlikely to viable for two reasons, Firstly due to inadequacy of water in Uma oya to be diverted to the South and secondly as it will badly affect supply to the Mahaweli project.

If these three proposals could be implemented we can achieve three objectives simultaneously namely,

a) Millions of gallons of water presently going down the Kelani, Kalu, Nilwala and GInganga to the sea could be saved for the benefit of man in the water deficit DZ

b) It could at least partly solve DZ drought hazards and water deficit. (a thing even the legendary Parakramabahu the Great could not do)

C) Control floods and silting of river basins in the SW.

I am presenting this as a combined overall proposal to solve the water shortage in the DZ and control floods and river silting in the SW. We must put an end to petty prejudices and put the welfare of the people living all over the Island. It is also high time for politicians and policy makers to realize that DZ water problem can no longer be solved by providing water by bowsers or by giving bottled water as a crash programme. Digging wells in the DZ could worsen the problem for two reasons. Firstly there is very little ground water to be tapped as the DZ for reasons pointed out by Sirimanne (1952). He pointed out that the un-weathered crystalline rocks (found in the undulating topography of the dry zone), by their very nature were relatively impervious and non porous and water circulation took place mainly around joints and fissures (cracks). P.G. Cooray, (an eminent Geologist) in a later study (1988) concluded: “there is, therefore, no continuous body of groundwater with a single water table in the crystalline rocks, but rather separate pockets of groundwater each with a distinct water table”. The utilization of such water pockets depends on their exact location in the underlying rock topography, and, therefore, haphazard well sinking in areas of crystalline rock often leads to failure. As such in addition to ground water being scarce and difficult to locate in these regions the drought conditions could be made even worse if the available little water is also tapped through wells.

9 Responses to “Mitigating Droughts in the Dry Zone of Sri Lanka. A Point of view”

  1. AnuD Says:

    Just after the construction of the polgolla dam and once Mahaweli water was turned to the Dry zone side, govt flattened many small tanks. Whose idea was that ?

    Now, they talk about droughts.

    Sri lanka does not have any long term plans, any environmental studies or any evaluation for long term.They just built and break. then break and built and start thinking and looking for answers later.

  2. Lorenzo Says:

    MASSIVE amounts of water is WASTED in Colombo City. Water prices for Colombo City should be DOUBLED. FREE water taps should be CLOSED DOWN.

    There should be MASSIVE PIPES taking water from WET ZONE to DRY ZONE.

    MOST affected people are SINHALESE. Jaffna, Batticaloa and MOST PARTS of Vanni have enough water.

  3. Nanda Says:

    “There should be MASSIVE PIPES taking water from WET ZONE to DRY ZONE. ”

    Already there are 2 massive pipes We call them Mahaweli and Walave Ganga.

    “Millions of gallons of water presently going down the Kelani, Kalu, Nilwala and GInganga to the sea could be saved for the benefit of man in the water deficit DZ”

    – Yes. It also solve he flooding problems in Rathnapura and Colombo. I believe Ratnapura catchment should be diverted to a massive reservoir at a higher level and canals towards dry zone in south east.

  4. Lorenzo Says:

    SCRAP the damn 13 amendment. PCs will go. It will save BILLIONS of rupees.

    Give these to drought affected people.

    FOOLISH govt. is wasting money on VIGNESWARAN and MAJEED because of this cursed 13 amendment.

  5. Lorenzo Says:

    Nanda,

    Natural rivers are not sufficient. As they do in China, etc. there should be artificial PIPELINES carrying water to where it is needed. This way water is SAVED from evaporation, misuse and absorption to soil along the way.

    Rainwater from WET ZONE should also be transported this way and stored in tanks in the DRY ZONE.

    If we do this there won’t be FLOODS in the wet zone and droughts in the dry zone.

    NO money to do it?

    SCRAP the damn 13 amendment and there you have MORE THAN ENOUGH MONEY.

    What matters most? Sinhala people’s RIGHT TO LIFE or Tamil people’s federal aspirations? Obviously the former.

    NFF, JVP and even UNP should make MAXIMUM political gains from the drought as they did in 2001. Then the foolish govt. will realize.

  6. Nanda Says:

    We sacrificed 26600 soldiers plus thousands of innocent citizens to KILL 1 bastard murderer.
    We cannot sacrifice the whole nation to save ONE bugger even though he is our father or brother.

    This bugger is appointing more and more deputy ministers, ministers , thieves to spend the hard earned money sent by mothers doing slavery to Muslims in the ME to save his ass.

    SCRAP the damn 13 amendment and there you have MORE THAN ENOUGH MONEY.

  7. Lorenzo Says:

    “We sacrificed 26600 soldiers plus thousands of innocent citizens to KILL 1 bastard murderer.
    We cannot sacrifice the whole nation to save ONE bugger even though he is our father or brother.”

    VERY TRUE.

    I was watching a small documentary done by some expats to show the impact of the DROUGHT on people and how MR appointed idiots and their appointed idiots are demanding the LITTLE MONEY they collected to be given to affected people.

    Heartless bastards. OBVIOUSLY MR is NOT aware of this. But by allowing this nonsense to continue, he is digging his own grave.

    IF the BILLIONS wasted on PCs can be saved (AND PC elections – the damn elections are in EVERY DAMN year), there is enough money to help all drought affected people.

    This drought is a BIG problem. Don’t wait till the election to realize how bad it is. Endia tied SL economy down by the 13 amendment curse.

  8. aloy Says:

    This is a very interesting and important article. Dr. Sudaths knowledge in this respect should be made use of by current and future governments, particularly his proposal to make area above 5000 ft a forest cover should be taken seriously. Since we have a labour shortage in the country the workers presently engaged in this area should be directed for other uses elsewhere. We should be able to even export water from this area.
    Dr. Sudaths ideas in item 4,5,6 and 9 needs particular attention.

  9. Asanga Says:

    I am sure many have seen this talk by Indian Environmentalist Anupam Mishra, but its such an inspirational talk and well worth listening to again; Its on the rain harvesting techniques of the remote desert areas of India.
    Imagine what can be done, even with the seasonal drought, using the knowledge of the ancients!-Just like the article of Dr. Gunsekera and all the comments above.

    https://www.ted.com/talks/anupam_mishra_the_ancient_ingenuity_of_water_harvesting

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