Village tank desilting, a national emergency | Sunday Observer

Village tank desilting, a national emergency

10 March, 2019
A village tank in need of de-silting
A village tank in need of de-silting

Today, the village tank is facing the most damning threat to its existence, silting, since the concept of taming waters for organised farming practices using irrigated water began in Sri Lanka millennia ago.

Fifty years ago, a tank was so deep that a few fathoms from the bund, water reached your chin level but now this is not so as the bathing ford has more silt than earlier.

With the current, weird vagaries of climate, villagers see their tank spillway overflowing after the first or second rain of the season. In our youth, this occurred every 2 or 3-years or even longer, and that too towards the latter half of the rainy season. As I wrote in the Daily News in 2004, ‘Water Ceremony at the Spillway,’ villagers thought it was a remarkable sight to behold in the same breath and awe as the famed irasevaya seen from atop Adam’s Peak.

Climate vicissitudes alone won’t explain the change of behaviour of the spillway. My guess is that the tank’s ‘Body Mass Index’(BMI) has changed over the years. I use this medical analogy, partly in jest and partly to highlight how gravely the high level of silt accumulation is now changing the geo-physiology of the tank.

Tanks and cascades

The village and its tank have an interchanging trustee-beneficiary relationship to take care of each other. Although located mostly above or adjoining the village proper (gammedda), tank is the centre of the community’s existence and the cosmic axis of the villagers’ livelihood.

In 1950, irrigation engineer S. Arumugam said that ‘a village is a tank and a tank is a village’. An early 20th century irrigation engineer J.S. Kennedy, wrote that a village irrigation system has an individuality and urged to identify the sense and substance of this individuality. No two village tanks are similar in geometry, topography, culture, and physical features. Such an indispensable asset is now at a cross road.

In 1985, Professor C.M.Madduma Bandara shed light on the manner of tanks joined in clusters forming unique patterns. He called such groups ‘Tank Cascades.’ These tank cascades represent stream basins that formed parts of a larger river system. In addition, to maximising the entrapment of each drop of water without wasting it, these cascades also controlled silt. Rank forest cover, in some instances with a kuluwewa, acted as micro-watersheds between each tank in the cascade separating them in to individual units,holding in check the silting process.

However, these are facing threats to their intended purpose – maximising resources of the stream(s) they share. A highly silted tank compromises the safety of the tanks in the cascade downstream as its ability to control floods is reduced due to sooner-than-used-to release of water from spill-ways of the tanks on the upper areas of the cascade. The culprit, again, is the ‘BMI’ totality of the cascade created by the silt.

Except for sharing the stream and the silt it carried, tanks in the cascades were comfortable with each retaining its individuality as it fulfilled their immediate necessities without compromising the larger geometry of the system.

Silt formation on the village tank bed is a multifaceted , varied process. It takes place with the action of natural causes and human and animal activities. Assiduous population growth in the last half of the 20th century has seen increased human activity like home building, home gardens and paddy fields into former ‘reservation’ lands, the wew thawalla portion between the watersheds and the tank proper. Modern ploughing with ultra-efficient machinery in newly created paddies adjacent to garden plots have aided in drastically stirring more silt.Before this, the use of water buffaloes for madweema, kept silt-generation to a minimum. Once the rank forest was gone, the tank below it was subject to all these destructive silt machinations.

As water settles in the tank, organic material - animal products and water plants - begins to do their job. When the tank bed begins to dry, dead salvinia settles down and petrify ankle-deep on the floor adding to its silt makeup. Salvinia is not limited to small village tanks. The Irrigation Department must take note that the latest victim of salvinia is the Mahakanadarawa Reservoir.

The lotus in the tank is another kin of salvinia with the same pernicious attributes. The Minneri Lavan, (lavan = grass) -floating islands of mat-like grass colonies in the water has established kinship ties with other plant matter to tamp the tank of its capacity to hold water.

Stepchild treatment

Although quintessentially the most basic, original, and important infrastructure conception in Sri Lanka, the village tank has become a stepchild due to larger irrigation reservoirs and city lakes because the Irrigation Department, which looked after all tanks regardless of their size and purpose, now boasts of taking care of larger irrigation reservoirs, and city centre water bodies like the Kandy Lake,and the Beira Wewa. .Villagers feel that such water bodies should be the responsibility of the municipality as was the case during Sri Lanka’s days of smart and fair governance.

It is incredible to the villagers that disproportionate sums of money are spent on, and more talking done on urban water bodies which are only act repositories of city run-off and liquified city waste and are of recreational and aesthetic comfort to city dwellers.

The village tank, needs its own BMI assessment immediately as decades of neglect has dumped an inordinate volume of silt on its bed, impeding its watering of the fields done since perpetuity.

Prior to the era of PCs funds for tank upkeep came primarily through the Irrigation Department. But now funding takes a circuitous route through every layer of the PC, and finally trickles down to the village with bureaucracy and corruption rampant. In the past, a Government Agent, a divisional revenue officer (DRO) and an engineer did the same work with speed and efficiency to nurture a village tank much better than the PCs.

Kattikapeema and Rajakariya

While the forested watershed kept the silt formation to a minimum, during the rajakariya days, villagers handled the little volume of silt on the tank bed. To avoid and compensate the possibility of the tank running out of water in the latter days of the crop maturing, villagers made an early start of seed establishment with the practice called kekulanwapireema before the Ak-Wehi– the first drizzles of the season.

Annually, during the dry months, villagers desilted under rajakariya with the practice, kattikapeema. The Velvidane, summoned share-holders of the field (pangukarayo) and assigned plot(s) (kattiya) to each according to the extent they owned to desilt and spread the silt on the tank bund.

The Rajakariya tradition mandated participation, while colonial laws at the time provided a minimal wage to the participants. The four-fold katti-kapeema removed stratified sediments from the tank floor, increased tank capacity, reinforced the bund, and strengthened the kinship bonds of the community.

Even during the waning years of feudalism and colonialism fuelled by the traditional knowledge of how and why these things are needed,the custom continued. In 1958, the Govi Karaka Sabha was introduced with democratic principles but totally dependant on the Government for tank maintenance. With this ,the Kattikapeema tradition became defunct.

This is not a suggestion to return to vile feudalistic ways but a hint that we must device a palimpsest of it with a modern and fair system of communal participation.

Here are what villagers have in mind to control silt. Trust the villagers. Work with the Govi Sanvidhana, a la Council of Elders in the village. Entrust adequate funds every two years to this Council. Ask the Council to devise a plan and a time to dig out soil from the tank bed and deposit it on the bund.

An indigenous solution?

The practice of contractors bringing tractor-loads of soil from someplace else and dumping on the bund would not remove a grain of silt from the tank bed. A contractor’s goal is only to make a profit but the Council will not misuse the funds, as villagers are usually dead set on protecting their most important communal asset. Proof of this is the neophyte Water Board of Residents which manage the running-water project of the village and its home-made Chartered Accountant who counts its monetary affairs with his own abacus – the ten fingers.

A village of 75 families does not need bureaucrats telling them how to keep their village tank in working order. It is in their blood; all they need is sufficient funds. The Council will do the work and apprise the villagers of the progress at monthly meetings.A Village Council of Elders is a much better alternative than the multi-layered complex process of funding by the Provincial Authorities.

Today, instead of worrying about micro-level infrastructure development such as village tanks, the peoples’ elected representatives are paying more attention to things like seating. When the chaotic seating is done, they spar with each other. A classic example of sinecure – getting paid without being required to work.

The village tank is the mother lode of the national food self-sufficiency effort and this requires the Government to have an equal and reasonable fiduciary relationship with the villagers who caannot desilt their treasure alone. They are willing to do a sterling job if the authorities assist with practical cost effective ways.

A clear and convincing palimpset like replacing the archaic Kattikepeema with novel ways of funding and participation of the likes of Citizen Councils to make a recrudescence of the old practice of silt removal to save the village tank.

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