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Climate change: Looming threats to irrigated agriculture in SL

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by Eng. Thushara Dissanayake

Sri Lanka boasts a legacy of massive ancient irrigation systems built by kings in the dry zone in ancient times. Parakramabhu the Great is believed to have said, “Let not even a drop of rain water go to the sea without benefiting man.” His words may have inspired the professionals in the water sector to develop the irrigated agriculture of the country further, harnessing high rainfall. Total annual renewable surface water resources in Sri Lanka is about 52 billion cubic meters (BCM), while total average annual rainfall is about 112 BCM.

Since the construction of the Senanayake Samudra in the 1950s as the largest reservoir in Sri Lanka, organizations in the water sector have completed many new reservoir projects of large capacities. Lunugamwehera, Weheragala, Deduru Oya, Kalugal Oya and Yan Oya are some of the recent achievements aimed at promoting irrigated agriculture.

The total storage capacity of major and medium irrigation reservoirs in Sri Lanka is about 3.4 BCM. In addition, major reservoirs constructed under the Accelerated Mahaweli Development Project are considered to be multipurpose as the main objective is the generation of hydro-electricity. Nevertheless, the contribution of the Mahaweli reservoirs to irrigated agriculture of the country is indispensable. With the newly constructed Moragahakanda-Kaluganga reservoirs, the total Mahaweli reservoir capacity stands at around 3.2 BCM. In addition, the total number of minor tanks in the country are estimated to be over 10,000, though the total water storage capacity is not accurately known.

 

Reliability of these reservoirs dependent on rainfall

Irrigated agriculture is the largest user of raw water in Sri Lanka. The country receives almost a constant volume of rainfall annually. But, this does not mean that we have no water issues. Generally, reservoir designs are based on past rainfall characteristics of the areas where they are located. Hence, they depend not only on annually expected rainfall volume but also the temporal pattern of rainfall. They will have the desired storage levels to cater to the demand only if they receive expected rainfall at the right time in the right quantity. In addition, it is important to ensure that the water withdrawal rates remain within the envisaged limits during the reservoir design. When rainfall becomes more variable within season and over time, reliability of reservoirs will decrease.

 

Climate change impacts reservoir operations

As explained above if a reservoir does not receive expected rainfall in right quantity in right time it will more or less fail to serve the water demand sites up to the expectation. On the contrary, if it gets rainfall more than expected during a operation cycle the additional amount of water may spill out of the reservoir and find its way to the the sea unless there are any other storage reservoirs downstream to receive it.

The climate change has caused rainfall to behave erratically. Technically speaking what we experience today is a temporal variation accompanied with fluctuation in intensities. Climate change experts predict that Sri Lanka will experience longer dry spells frequently in the future. During such dry spells, often unforeseen, our reservoirs would be incapable of supplying the irrigation water demands continuously throughout the cultivation season.

The global warming or the increase in atmospheric temperature is the root cause of climate change. Hence, the other major impact of climate change is an increase in evapotranspiration. As a consequence, water requirement of the agricultural crops goes up demanding more water from reservoirs. In the meantime, water losses from the reservoirs themselves by way of evaporation will also go up. These scenarios will create more water stresses on irrigated agriculture in future.

When the conditions are not favourable for agriculture there will be a sharp decrease in people engaged in agriculture abandoning their lands. Hence, this crisis should not be understood merely as a water crisis as it has the potential to have ramifications in other social and economic spheres. Therefore, the decrease in agricultural production will lead to higher selling prices, which neither the government nor the consumer is happy about.

 

Possible interventions to

resolve the issue

We are not in a position to control a natural phenomenon like rainfall nor to predict the pattern of climate change and its impacts in future accurately. Hence, only option available with us is improving our water management strategies and practices. The construction of storage reservoirs wherever possible will only be a part of the solution. However, we have utilized or identified almost all possible locations for reservoir construction by, now and most of the remaining places have high social and environmental implications.

 

Under these circumstances some alternatives that may be use to the stakeholders concerned are discussed below. It should be acknowledged that some of these concepts are already in practice but in an ad hoc manner. What is needed is to implement them with clear goals and monitor and assess the outcomes after implementation.

 

Irrigation system modernization

We are not in a position to control a natural phenomenon like rainfall. Besides, we are not able to predict the pattern of climate change and its impacts in the future accurately. Hence, only option available to us is improving our water management strategies and practices.

At present the actual water requirement for producing 1kg of paddy is around 2,500 – 3,500 litres while the crop requirement is about 1,400 litres. This higher requirement is mainly due to the water losses during conveyance and application. Our overall irrigation water use efficiencies are assumed to be just 40 per cent, though no adequate research has been done on this at the field level to calculate it accurately systemwise.

Currently, many countries are working on irrigation modernization (IM) to ensure sustainable irrigated agriculture. The Food and Agriculture Organization (FAO) defines IM as “a process of technical and managerial upgrading (as opposed to mere rehabilitation) of irrigation schemes combined with institutional reforms, with the objective to improve resource utilization (labour, water, economic, environmental) and water delivery service to farms”. Simply speaking, IM consists of a set of interventions to improve water management and level of on-farm services to farmers, which eventually leads to improved crop production and resilience to climate change under the present context. It includes both engineering and management interventions.

These interventions for better water management are mainly as follows:

 

1. Upgrading of water conveyance systems so that evaporation and infiltration losses can be minimised. Deficient canals are replaced with concrete lined canals and underground pipes

2. Process improvement in water allocation to farmers with modern techniques like supervisory control and data acquisition (SCADA), that intervenes in the process without changing the rules of the water management

3. Pragmatic desilting of reservoirs to regain their original capacities where applicable

4. Improvement of agricultural roads and access roads in farming areas to facilitate easy operations and management

5. Capacity building of farmers

 

Watershed conservation

All the irrigation systems are not reservoir-based. There are large number of anicut-based minor irrigation systems. They depend water diverted from rivers or streams. The success of these systems depends on the water availability of rivers and streams.

During rain, a considerable portion of water infiltrates into the ground, and rivers and streams are fed gradually by this groundwater making them perennial. For this mechanism, forests in the river basins play a major role by delaying rain water runoff, which in turn helps ground water recharge. Yet, the issue is diminishing forest cover in our watersheds. This rate of forest cover reduction will adversely affect ground water infiltration and eventually result in dried up rivers and streams. Further, agriculture depending on ground water will face water stresses. Hence, importance of watershed conservation goes without saying.

 

Farmers’ responsibilities and the role of the extension services

Sri Lankan farmers are supplied with irrigation water free. This does not mean that water does not involve any costs. Even though the relevant authorities could intervene to minimise conveyance water losses of the systems, the control of water application is mainly in farmers’ hands. Therefore, they also have a big role to play in minimising water application losses.

Traditional water application methods should be replaced with best water saving methods. The method known as alternative wetting and drying (AWD), introduced a long time ago, is a water management technique practised in paddy cultivation that need much less water than the usual practice of keeping standing water in the paddy field and proven to give higher yields. In areas where water stress is frequent crops that require less water should be grown with appropriate cultivation methods. If there is an evident shift in rainy season, crop cultivation periods can be adjusted to allow earlier or later planting so that both coincide, in order to reduce irrigation water use.

Where most of the farmers are concerned, dominant factor in the crop selection process seems to be market price and not giving enough attention to crop water requirements. In some cases, it is the farmers’ status quo that matters. Hence, relevant authorities should carefully focus on these issues when they render their extension services to the farmer community. In this respect, better inter-agency cooperation and communication and active participation are essential. No need to mention how the modern technology can be used by the authorities for creating an effective work environment.

 

Final remarks

 

The focus of this article has been on looming threats to our irrigated agriculture and discuss few proactive measures briefly and the increasing demand for food due to increasing population has not been factored in. Implementing aforesaid proactive measures need the dedicated action of many players including politicians, public sector organisations and the farmer community. Failure to take prompt action will result in additional stress in food production in the future and that in turn will affect the economy of the country as more and more food items will have to be imported.

(The writer is a chartered Civil Engineer. This article is based on his personal views and does not reflect those of the organisations where he holds positions.) 



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Features

Strong on vocals

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The group Mirage is very much alive, and kicking, as one would say!

Their lineup did undergo a few changes and now they have decided to present themselves as an all male group – operating without a female vocalist.

At the helm is Donald Pieries (drums and vocals), Trevin Joseph (percussion and vocals), Dilipa Deshan (bass and vocals), Toosha Rajarathna (keyboards and vocals), and Sudam Nanayakkara (lead guitar and vocals).

The plus factor, where the new lineup is concerned, is that all five members sing.

However, leader Donald did mention that if it’s a function, where a female vocalist is required, they would then feature a guest performer.

Mirage is a very experience outfit and they now do the Friday night scene at the Irish Pub, in Colombo, as well as private gigs.

 

 

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Dichotomy of an urban-suburban New Year

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Ushered in by the ‘coo-ee’ of the Koel and the swaying of Erabadu bunches, the Sinhala and Tamil New Year will dawn in the wee hours of April 14. With houses to clean, preparation of sweetmeats and last-minute shopping, times are hectic…. and the streets congested.

It is believed that New Year traditions predated the advent of Buddhism in the 3rd century BC. But Buddhism resulted in a re-interpretation of the existing New Year activities in a Buddhist light. Hinduism has co-existed with Buddhism over millennia and no serious contradiction in New Year rituals are observed among Buddhists and Hindus.

The local New Year is a complex mix of Indigenous, Astrological, Hindu, and Buddhist traditions. Hindu literature provides the New Year with its mythological backdrop. The Prince of Peace called Indradeva is said to descend upon the earth to ensure peace and happiness, in a white carriage wearing on his head a white floral crown seven cubits high. He first plunges, into a sea of milk, breaking earth’s gravity.

The timing of the Sinhala New Year coincides with the New Year celebrations of many traditional calendars of South and Southeast Asia. Astrologically, the New Year begins when the sun moves from the House of Pisces (Meena Rashiya) to the House of Aries (Mesha Rashiya) in the celestial sphere.

The New Year marks the end of the harvest season and spring. Consequently, for farming communities, the traditional New Year doubles as a harvest as well. It also coincides with one of two instances when the sun is directly above Sri Lanka. The month of Bak, which coincides with April, according to the Gregorian calendar, represents prosperity. Astrologers decide the modern day rituals based on auspicious times, which coincides with the transit of the Sun between ‘House of Pisces’ and ‘House of Aries’.

Consequently, the ending of the old year, and the beginning of the new year occur several hours apart, during the time of transit. This period is considered Nonegathe, which roughly translates to ‘neutral period’ or a period in which there are no auspicious times. During the Nonegathe, traditionally, people are encouraged to engage themselves in meritorious and religious activities, refraining from material pursuits. This year the Nonegathe begin at 8.09 pm on Tuesday, April 13, and continues till 8.57 am on 14. New Year dawns at the halfway point of the transit, ushered in bythe sound of fire crackers, to the woe of many a dog and cat of the neighbourhood. Cracker related accidents are a common occurrence during new year celebrations. Environmental and safety concerns aside, lighting crackers remain an integral part of the celebrations throughout Sri Lanka.

This year the Sinhala and Tamil New Year dawns on Wednesday, April 14, at 2.33 am. But ‘spring cleaning’ starts days before the dawn of the new year. Before the new year the floor of houses are washed clean, polished, walls are lime-washed or painted, drapes are washed, dried and rehang. The well of the house is drained either manually or using an electric water pump and would not be used until such time the water is drawn for first transaction. Sweetmeats are prepared, often at homes, although commercialization of the new year has encouraged most urbanites to buy such food items. Shopping is a big part of the new year. Crowds throng to clothing retailers by the thousands. Relatives, specially the kids, are bought clothes as presents.

Bathing for the old year takes place before the dawn of the new year. This year this particular auspicious time falls on April 12, to bathe in the essence of wood apple leaves. Abiding by the relevant auspicious times the hearth and an oil lamp are lit and pot of milk is set to boil upon the hearth. Milk rice, the first meal of the year, is prepared separate. Entering into the first business transaction and partaking of the first meal are also observed according to the given auspicious times. This year, the auspicious time for preparing of meals, milk rice and sweets using mung beans, falls on Wednesday, April 14 at 6.17 am, and is to be carried out dressed in light green, while facing east. Commencement of work, transactions and consumption of the first meal falls on Wednesday, April 14 at 7.41 am, to be observed while wearing light green and facing east.

The first transaction was traditionally done with the well. The woman of the house would draw water from the well and in exchange drop a few pieces of charcoal, flowers, coins, salt and dried chillies into the well, in certain regions a handful of paddy or rice is also thrown in for good measure. But this ritual is also dying out as few urban homes have wells within their premises. This is not a mere ritual and was traditionally carried out with the purification properties of charcoal in mind. The first water is preferably collected into an airtight container, and kept till the dawn of the next new year. It is believed that if the water in the container does not go down it would be a prosperous year. The rituals vary slightly based on the region. However, the essence of the celebrations remains the same.

Anointing of oil is another major ritual of the New Year celebrations. It falls on Saturday, April 17 at 7.16 am, and is done wearing blue, facing south, with nuga leaves placed on the head and Karada leaves at the feet. Oil is to be applied mixed with extracts of Nuga leaves. The auspicious time for setting out for professional occupations falls on Monday, April 19 at 6.39 am, while dressed in white, by consuming a meal of milk rice mixed with ghee, while facing South.

Traditionally, women played Raban during this time, but such practices are slowly being weaned out by urbanization and commercialisation of the New Year. Neighbours are visited with platters of sweetmeats, bananas, Kevum (oil cake) and Kokis (a crispy sweetmeat) usually delivered by children. The dichotomy of the urban and village life is obvious here too, where in the suburbs and the village outdoor celebrations are preferred and the city opts for more private parties.

 

 

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New Year games: Integral part of New Year Celebrations

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Food, games and rituals make a better part of New Year celebrations. One major perk of Avurudu is the festivals that are organised in each neighbourhood in its celebration. Observing all the rituals, like boiling milk, partaking of the first meal, anointing of oil, setting off to work, are, no doubt exciting, but much looked-forward-to is the local Avurudu Uthsawaya.

Avurudu Krida or New Year games are categorised as indoor and outdoor games. All indoor games are played on the floor and outdoor games played during the Avurudu Uthsava or New Year festival, with the whole neighbourhood taking part. Some of the indoor games are Pancha Dameema, Olinda Keliya and Cadju Dameema. Outdoor games include Kotta pora, Onchili pedeema, Raban geseema, Kana mutti bindeema, Placing the eye on the elephant, Coconut grating competition, Bun-eating competition, Lime-on-spoon race, Kamba adeema (Tug-o-War) and Lissana gaha nageema (climbing the greased pole). And what’s an Avurudhu Uthsava sans an Avurudu Kumari pageant, minus the usual drama that high profile beauty pageants of the day entail, of course.

A salient point of New Year games is that there are no age categories. Although there are games reserved for children such as blowing of balloons, races and soft drinks drinking contests, most other games are not age based.

Kotta pora aka pillow fights are not the kind the average teenagers fight out with their siblings, on plush beds. This is a serious game, wherein players have to balance themselves on a horizontal log in a seated position. With one hand tied behind their back and wielding the pillow with the other, players have to knock the opponent off balance. Whoever knocks the opponent off the log first, wins. The game is usually played over a muddy pit, so the loser goes home with a mud bath.

Climbing the greased pole is fun to watch, but cannot be fun to take part in. A flag is tied to the end of a timber pole-fixed to the ground and greased along the whole length. The objective of the players is to climb the pole, referred to as the ‘tree’, and bring down the flag. Retrieving the flag is never achieved on the first climb. It takes multiple climbers removing some of the grease at a time, so someone could finally retrieve the flag.

Who knew that scraping coconut could be made into an interesting game? During the Avurudu coconut scraping competition, women sit on coconut scraper stools and try to scrape a coconut as fast as possible. The one who finishes first wins. These maybe Avurudu games, but they are taken quite seriously. The grated coconut is inspected for clumps and those with ungrated clumps are disqualified.

Coconut palm weaving is another interesting contest that is exclusive to women. However men are by no means discouraged from entering such contests and, in fact, few men do. Participants are given equally measured coconut fronds and the one who finishes first wins.

Kana Mutti Bindima involves breaking one of many water filled clay pots hung overhead, using a long wooden beam. Placing the eye on the elephant is another game played while blindfolded. An elephant is drawn on a black or white board and the blindfolded person has to spot the eye of the elephant. Another competition involves feeding the partner yoghurt or curd while blindfolded.

The Banis-eating contest involves eating tea buns tied to a string. Contestants run to the buns with their hands tied behind their backs and have to eat buns hanging from a string, on their knees. The one who finishes his or her bun first, wins. Kamba adeema or Tug-o-War pits two teams against each other in a test of strength. Teams pull on opposite ends of a rope, with the goal being to bring the rope a certain distance in one direction against the force of the opposing team’s pull.

Participants of the lime-on-spoon race have to run a certain distance while balancing a lime on a spoon, with the handle in their mouths. The first person to cross the finish line without dropping the lime wins. The sack race and the three-legged race are equally fun to watch and to take part in. In the sack race, participants get into jute sacks and hop for the finish line. The first one over, wins. In the three-legged race one leg of each pair of participants are tied together and the duo must reach the finish line by synchronising their running, else they would trip over their own feet.

Pancha Dameema is an indoor game played in two groups, using five small shells, a coconut shell and a game board. Olinda is another indoor board game, normally played by two players. The board has nine holes, four beads each. The player who collects the most number of seeds win.

This is the verse sung while playing the game:

“Olinda thibenne koi koi dese,

Olinda thibenne bangali dese…

Genath hadanne koi koi dese,

Genath hadanne Sinhala dese…”

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