Just desilting the tanks is not enough!

Over the past several days we have had numerous opportunities to speak with villagers here in the Dry Zone of Sri Lanka. These hard-working cultivators are carrying on a tradition of rice growing that is thousands of years old. Yet they are firmly planted in the contemporary world of global communications and commerce. The traditional irrigation systems that were established by their ancestors, while still limping along, are severely impacted by a number of influences. 

For example, the agricultural chemicals, fertilizers, pesticides, and herbicides marketed by my country and other Western nations have resulted in severe health problems such as rampant kidney disease, which has introduced high rates of morbidity and mortality to the rural population. These same chemicals have perturbed the aquatic environment, leading to eutrophication, which has killed off native plants and fish species, favoring invasive introduced pest species.

 

A major problem that everyone has spoken about is the silting over of the agricultural waterways. In traditional times, silt was removed from the irrigation tanks periodically every six or seven years. When control of the tanks was taken over by the central government, villagers stopped taking responsibility for their maintenance. So in many cases here in the Dry Zone, silt has been collecting for 20, 30, 40 or even 50 years. It lies several feet deep in places and it has severely impacted the water retention capabilities and overall functioning of the tanks. 

Everyone wants to desilt their tank. No one we spoke to wants to do it by the traditional methods. So desilting means bringing in a backhoe and removing a foot or so of silt from the muddy area close to the dam. This practice provides more capacity for the tank but only temporarily. It also changes the contours of the tank bottom, which in the past provided the tank with complex functions of distributing and filtering water differentially. 

Tanks that are desilted today will start silting over tomorrow. What can be done about this? The tank systems have been severely perturbed, partly by road building, partly by the placement of culverts, partly by overgrazing, and partly by the destruction of native vegetation that complemented tank function in the past. 

It's easy to suggest that villagers plant more perahana and gasgommana plants (tall reeds, shrubs, and trees that filter and purify the water). Another great idea is to preserve the severely degraded  Kattakaduwa (shown above) in which villagers have started growing pet fish for international export. But all this takes social, political, and financial will. In our own society we lack the will to deal with seemingly intractable problems like poverty and racism. Our rampant consumption of resources has destroyed global ecology in an unprecedented manner. Can we in good conscience pretend to know what villagers should do to improve their degraded environment? Clearly, more questions have arisen since we began this research than we ever expected possible. We are very far from answers.

This reminds me of a colleague of mine, a sociologist. She spent two weeks interviewing rice growing villagers in southeast Asia through a translator and after that considered herself enough of an expert to publish a book. I don't need to rain on her parade but I do have to ask, with the complexity of problems we encounter, with the obvious language barriers, and with the seemingly insoluble issues we learn about when we spend the time, how can we claim expertise in a period of several days?

I leave it to you to decide. But from a standpoint of physical geography, topography, and soil science, simply desilting the tanks will not suffice. I look forward in these upcoming months of my Fulbright to lots of conversations that may shed more light on this issue. 

Deeper than I ever expected

Janet and I have been greeted by Sri Lankan colleagues and students with a kind of generous trust and welcoming openness that goes further than I had ever hoped for. Concomitantly we have gotten more deeply involved in the work of international cultural exchange than I ever expected. 

This morning we took a second foray into the field. Up here in the Dry Zone near Anuradhapura the wet season has begun, with rain aplenty every afternoon. Mornings are generally clear and hot and after a little back and forth my colleague, Dr. Nimal Abeysingha and I decided to take the risk. Thanks to his super organized hard work on the backside of a four-day weekend, Dr. Abeysingha arranged a van, five undergraduates , and a lecturer in soil science to join us. 

Janet led three of the students, from the social sciences faculty at the main campus in Mihintale, in interviewing local villagers on their use of the tank, their concerns, and their outlook for the future. I tagged along with Nimal, two students, and the lecturer traversing the tank, where we took over 50 soil samples for analysis. 

Our goal was to map the water retention ability of soils throughout the tank, as well as to measure their nitrogen and phosphorus content. Ultimately the question is whether the degraded perahana at Ulankulam is protecting the tank below it from eutrophication. 

Eutrophication would seem to be only one part of the problem in this beautiful but severely degraded tank environment. Villagers told Janet and her crew that silting is a major problem, reducing the water-holding capacity of the tank and directly affecting the amount of rice that can be grown. 

The villagers reported that many fewer acres are being cultivated by ever fewer people. It would appear to be dire straits but another look suggests "it ain't over til it's over." For example in the severely degraded kattakaduwa (the traditionally moist, wild region just outside the tank below the bund) the villagers are growing pet fish for international export. The kattakaduwa may be degraded, the tank may have low holding capacity, fewer people may be engaged in rice cultivation   yet life goes on and life is good.

My work for this Fulbright is a study of Sri Lankan landscapes in transition. Nothing says transition more than the tank-based villages around Ulankulama. The tank itself is shallow, only about nine feet deep during the wet season, but for a deep and deepening experience in international cultural exchange this Fulbright is turning out to be much more than I expected. 

Cultural exchange opportunity: A day with the villagers of Alisthana

Here we are exactly ten days into our Fulbright in Sri Lanka. It has been kind of super saturated experience with more cultural exchange then you might fit into a whole year normally. I think we got a running start thanks to several months of correspondence with colleagues here, so once we hit the ground there was already a lot to do. 

A week ago we arrived in Anuradhapura. Well, not exactly. The train we had boarded in Colombo made us sudden stop in Talawa, about 20 minutes south of here. My colleague Nimal Abeysingha, a lecturer at Rajarata University who planned to fetch us in Anuradhapura, was just a phone call away. Luckily, his wife Sandia is head of the local secretariat in Talawa and she was able to tell him what the situation was. Ever solicitous, Abey's concern for us could easily have turned to major worry on his part. Long story short, we spent a day in the field with Abey and colleagues and I had the pleasure of delivering a lecture to his students a few days ago. I hope they enjoyed it as much as I did! Today, Sunday, we are planning for second day in the field tomorrow with Abey and his students. 

Backtrack to yesterday when we had the most amazing experience, visit with the agricultural villagers of Alisthana. The visit was arranged by my colleague Dr. MUA Tennakoon, the Executive Director of SAP SRI, an NGO that has collaborated with the villagers on several development projects. 

My wonderful driver from Mihintale, Mr. Amara, brought us to the village. We made good use of his abundant energy and good cheer to act, as well as he could, as a translator for the goings-on. Turns out Amara brings tourists to the Alisthana tank on a regular basis on his way to Polonowurra just for the scenery, so at the end of the day this provided him with new contacts. Maybe it will develop into something the villagers can capitalize on in terms of tourism. 

We called Dr. Tennakoon's deputy, Mr. Ranatunghe, from the embankment of the incredibly scenic Alisthana tank and he arrived on his motorcycle in a few minutes. A quick walk along the bund gave us a chance to take in the scenery and especially to see the rare measuring rock just across from the main sluice gate. Ranatunghe kept looking at his watch, an uncomfortable Western sort of action, and I started to wonder if he was trying to get rid of us. Quite to the contrary, he told Amara that the villagers had assembled in anticipation of our arrival and were waiting to meet with us. This was a rare honor that I was barely prepared for, much less expecting.

A five minute ride and we were in the house where we were to meet. Several men sat on plastic chairs outside and we were ushered into the shade of the main room of the house once we had taken off our sandals. Janet and I were invited to sit on the large comfortable couch and across from us in a lineup of chairs sat the ladies of the women's agricultural community of Alisthana. After a short introduction by Mr. Ranatunghe we were put more or less on our own to develop a conversation with the ladies. They had anticipated the meeting by bringing several record books with them. They opened the books for us and showed us the columns of numbers that represented loans from SAP SRI, how the monies were invested, and dates when they were paid back. Amara explained that we were also being shown the minutes of several months of regularly held meetings, attendance lists, and agenda items.

One thing that struck me was relatively small amount of money that was being recorded. At least in terms of Western currency this seemed to be less than pocket change, certainly a great return on investment considering what the villagers have been busy doing. 

A sort of crescendo to our meeting, which was filled with laughter, clowning, and good cheer, was when the ladies voiced a request to Janet. They told her that since some of them are older and their eyesight isn't what it used to be, they could use an visiting eye clinic in the village. Janet wisely asked whether this was for sewing and reading or for distance. She surmised that people were struggling with close-up vision and that some inexpensive reading glasses could probably solve most of the vision problems that the ladies were talking about. As an aside, or so I thought, she also asked them about delivering babies, which most people do right in Thirappane. Complications are moved to the hospital in Anuradhapura. Later as we were taking apart the events of the day Janet conjectured why a simple trip to Anuradhapura couldn't solve the problem of reading glasses. This solution, which she only needed a few hours to figure out, was a lot easier than bringing in a team of experts from Boston!

We finished up with the ladies with a very jolly photo op on the front veranda and then Amara informed us it was time to meet with the gentleman. I was hoping we could stay outside where they were sitting but soon we were ordered back into the front room where again we were seated on the couch with the gentleman lined up across from us on chairs. We started the meeting with a little less aplomb than before maybe because, as Amara later told us, these meetings with village gentlemen usually start with some deep frowning before rapport and good humor are established.  

I had remembered to pack a couple of tins of chocolate covered coffee beans, and the men seemed to enjoy them as much as the women. Conversation was a little slower getting off the ground but finally I decided to ask a few questions that set off lots of discussion. What about GMO seeds in the village? Use of pesticides? Fertilizers? What about the different kinds of rice and the price of rice? Soon we found ourselves with plates of dry rice on our lap a great opportunity to feel,  smell, and taste what we were being shown. As a foreigner in a situation like this I felt reassured to fall back on simple human actions like tasting and smelling and I hope this gave our hosts a mutual feeling of comfort and shared humanity.  

Having heard the ladies' concern about eyeglasses, Janet decided to ask the men about the major obstacle in growing their crops. Unanimously it seemed, the men complained about silt in the tank. They outlined a plan of action that would include a bulldozer and backhoe, and which would take about a week during which they could conceivably desilt part of the tank, thereby increasing its water holding capacity. 

To tell you the truth I was a little bit shocked to hear about this desire on their part, having come to Alisthana with some knowledge of the projects sponsored by SAP SRI as the planting of 8000 saplings and numerous reed beds that are meant to reduce silting activity using natural vegetation. This is one I had to sleep on and it wasn't until this morning that I rethought the question about silt and its role in the tank ecosystem, not as something entirely bad but something that has its utility and function in the tank.

Our meeting with the gentleman ended with plenty of good cheer, my business cards seeming to be the party favor of the moment, and another photo op on the veranda. With many handshakes and fond goodbyes (I forgot to write about the long heartfelt parting speeches that were made both by the ladies and gentlemen, thanking us and inviting us to return) we were settled back into Amara's tuktuk and taken to a series of village houses where in a sense, our tour of Alisthana actually started. 

First we were brought to a large home garden, neatly maintained and weeded, with carefully made raised beds and a sturdy the fence with bitter gourd growing on it. The garden was mostly different varieties of chile, which we were told is relatively expensive, and there were assorted vegetables, spinach, tomatoes, eggplant, and different herbs. Located in the shade of several trees in the garden, this was a peaceful, comfortable spot. And thanks to the trees, the raised beds, carefully arranged compost, and the watchful eye of the gardener herself, the water hose was probably not used that extensively, even now in the height of the dry season. 

We were treated to coconut juice, which the ladies had also served us during the meeting, along with a delicious slice of papaya and cups of tea. We were shown two types of beehive, A traditional log beehive, and a government issued box beehive. Lots of good humor as we swapped garden stories and spoke for a couple of minutes about our own vermicomposting work at home in Boston. 

We were taken to another garden where according to what we were told, the lady's garden was so orderly and lovely that government agents quickly afforded her a permit for drilling a tube well and the funds to do it. I came to understand something Dr. Tennakoon and I had discussed on the way in from the airport the other night. I was concerned that tube wells could lower the water table. I realized when I saw this lady's tube well, that home extraction is so low, just a bucketful here and there, that the impact on the overall water table has to be negligible. I realized as well that there needs to be some kind of limit on how many tube wells are put in and how people use them in order to preserve the water table that the tanks complement. 

An amazing thing we saw at this particular house was a wild bee colony, a sort of disc-like wax construction covered with bees, simply hanging from a tree. Three small boys were playing around in a great looking tree house that had been built for them, and I asked the lady "three boys?!" "No, only two," she answered. "One of them is a neighbor. That's how I have enough time for the garden." And very fine garden it was!

We were brought to a third house, greeted very graciously, and then taken in back of the house to a trail that led to the high ground of the tank. Here I learned something that I guess I should have perceived before, that the gasgommana and the perahana are spatially interchangeable. They comprise a kind of mosaic with varying types of vegetation, trees, shrubs, grasses, and reeds, and all of them are part of a continuum of the "touwleh," or  catchment area. 

We walked about 500 m, something that Dr Tennakoon was worried we might not be capable of achieving (!) with eyes wide open to the beauty of the tank, the vegetative composition around us, the small natural elephant tank, and most significant the 8000 saplings. 

We were told that there are at least five species of saplings that were planted. Janet asked about how they were raised and we were told they were raised from seed by the villagers in small nurseries that they prepared at their homes. This represented quite a massive effort that must have taken a lot of coordination and certainly a very high level of participation on the part of the villagers. 

The young saplings, we were told, are not attractive to elephants or other wildlife so they stand a good chance of surviving. What we saw with her own eyes was very robust looking saplings that seem to portend good future for the gasgommana. Mr. Ranatunghe gave us a great idea of the local geography here, pointing out the lower rice fields (kottovelha) that are fed by the tank just above Alisthana. Traditionally, gasgommana would have separated the two tanks but in recent times the gasgommana forest was degraded, leaving a kind of no mans land between one tank and another. This no mans land could become overgrazed, subject to erosion, and contribute to another source of unwanted tank silting.  

The new saplings were planted as a way to change a no mans land info a productive ecological zone. In the same way, our full day in Alisthana changed what was formerly an impenetrable landscape into one I understood better. Landscape analysis, especially the uncovering and analysis of intangible landscapes, is the goal of my Fulbright project here in Sri Lanka. Our day in Alisthana, generally hosted by the villagers brought me closer to that goal. 

My distinct impression is that the villagers have made an investment on behalf of their grandchildren. They are bucking a global pattern of young people moving to cities with a unique local solution. Now time will tell whether the upcoming generations are interested in cultivation and indeed whether they are interested in staying in the villages. 

Society of Silt

Yesterday when we met with the mens' community of Alisathna here in the Dry Zone of Sri Lanka, the first problem they conveyed to us was the buildup of silt in their tank. The "tanks" (named thus by Portuguese cartographers who depicted them in 16th century maps) are human-built lakes that have irrigated and nourished this agricultural landscape of Sri Lanka for centuries. Because the tanks hold and control water they are also susceptible to the buildup of silt. Rural Sri Lankan society evolved around the village tank. By extension we may posit that it's a society preoccupied with silt. 

Silt may enter the tank in suspension or solution, and thanks to the tank comprising its own micro-ecosystem there are methods for reducing the buildup of silt. The Alisthana villagers, in cooperation with SAP SRI, an NGO funded by the UNDP and GEF, have planted some 8000 saplings that are native to tank ecosystems. The saplings, which were planted close together, will form a revitalized gasgommana, the protective girdle of trees that line a healthy tank, shading it, purifying its water, and reducing the impact of rushing water. Part of, and just in from the gasgommana grows the perahana, an area of grasses and reeds, which filters the water further. 

But the villagers' work with SAP SRI is only 14 years old. Their tank was collecting silt for decades before they began these interventions. I've been told that some tanks may lie under two feet or more of silt, which affects seriously their capacity to hold water. This affects how much water is available for irrigation and it follows that the amount of rice that can be grown is impacted by the buildup of silt. 

Thus our conversation of yesterday. Desilting tanks by heavy machinery, which is what the mens' community wants to do, is a destructive practice that disturbs the anatomy and morphology of the tank. As tank function is impacted so is its ability to maintain itself, and the once complex functions of the tank, which involved filtering and distributing water differentially, are simplified and ultimately lost. 

Yet people have been desilting tanks for as long as tanks have been in existence. Silt was traditionally used to reinforce the bund (dam), as well as to build smaller, secondary protective structures that control the circulation of water in the tank. Silt was used in the manufacture of bricks that we see all over the ancient city of Anuradhapura, including the gigantic stupas here. I'm told that in the dry season villagers still set up kilns for brickmaking in the dry upper portions of the tank. 

We don't know that much about how silt was removed in ancient times. Perhaps some of the heavy work was done with elephants. One report I heard is that the muddy water was churned up and its silt emptied through a special "silt" sluice that is not in evidence today. 

So rather than bemoan the buildup of silt in the tanks Janet has encouraged me to look at silt in a different way. Like the gasgommana and the perahana, like the bund, the sluice gates, and the spillways, silt is part of the tank ecosystem. It's something to be used and benefitted from, not something we should try to eradicate. 

Yesterday I grabbed some handfuls of muddy silt from different tank bottoms. In some tanks it's dark with organic matter, elsewhere it's lighter. It's has a distinct odor, different in different tanks, and its clayey consistency is full of promise. It's a kind of plastic substance, something we may be able to shape into still-unknown uses. Like the world of rural Sri Lanka and like the many Sri Lankan people I've met, tank silt is tough yet pliable, unique in its character and composition. Like the tanks in which it's deposited, silt holds lessons for us we still haven't learned.