By Chandre Dharmawardana, Canada

Emeritus Professor Ariyasena de Silva of Moratuwa University, writing in The Island (1st Dec. 2019) suggests the following.

“[making] blocks one metre long and 0.5 m across … outside plastered with a thin layer of cement mortar … Compressing the garbage into a steel casing can also be done with a press made locally. If the blocks are sunk, at about 0.25 km away from the coast where the depth is roughly about three meters, a wall of one to two km in length can produce a land area of 0.25 sq km. Once the wall is built the normal garbage can be dumped as it is collected … It has to be a job lasting several years, but it can be done in smaller sections and the land put to some use. Perhaps (growing) coconuts will be the best. Rainwater storage in the land must also be considered. The equipment can be totally built by our youth … and it may even be possible to grow some leafy food like Mukunuwenna.

Those who value the beauty of Sri Lanka’s beaches will find the proposal quite unacceptable. However, let us examine it further.

The engineering professor was led to this idea because rubble from buildings demolished during World War II were used in building the coast line of the USA. However, since then, our knowledge of the ecosystem and the inter-relatedness of the web of life has grown by leaps and bounds. Various international conventions exist regarding what can be disposed in the sea even within territorial waters.

Almost all countries are party to the “Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 (the London Convention) and the related the 1996 Protocol”. These agreements are there because what is dumped in Chennai or New York may have non-local effects even on Sri Lanka’s coasts, and vice versa

Garbage is not some inert material like rubble from demolished buildings. It is a living ecosystem full of microbes and bugs. The microbes are feasting on the bio-degradable components of garbage and producing a lot of greenhouse gases like methane and carbon dioxide. That is why composting which allows such gases to escape into the environment (instead of being harvested) is very bad. Such gases cause global warming. Furthermore, if the garbage is compressed and encapsulated, the aerobic processes become anaerobic, but gases are produced, and the blocks proposed by Prof. De Silva will eventually explode or crack open. Even the garbage compressed inside large open garbage mounds explode from time to time, as has happened several times in Meethotamulla.

Professor de Silva envisions that blocks of encapsulated garbage could be used to form a wall in the sea. From then on, he suggests using the space between the wall and the sea coast as a landfill for garbage where one can eventually plant coconuts and even grow “Mukunuwenna”. Urban garbage is rather rich in metal toxins like cadmium, lead and arsenic, as well as industrial pollutants, petro-chemical residues, excreted or discarded pharmaceuticals, electronic waste etc. If crops are grown on soil containing such rotting garbage, or compost made from such garbage, the toxic substances present therein are also absorbed by the Mukunuwenna or Murunga grown there. There is also a mechanism known as phyto-magnification, whereby the toxins accumulate and concentrate in the crops, sometimes up to a factor of 100 times more. That is, toxins concentrate as you go up the food chain. So, the Mukunuwenna is even more toxic than the soil ecosystem.

Your food is only as clean as the soil and water used to grow crops! Of course, the false propaganda is that all the pollution come from agrochemicals. Actually, such pollution and toxicity from agrochemicals are utterly minuscule compared to that of other sources. However, it makes good propaganda for the “organic food” marketeers who promote their products and cater to the elite, while destroying the agriculture that feeds the vast majority of poor humanity. The Yahapalanaya government followed the appalling agricultural dicta of Ven. Ratana and his minions who claim to get their “science” from God Natha, and banned the herbicide glyphosate in 2015. Sri Lanka’s key agricultural sectors are yet to recover from that crippling blow that cost the country far more than the Bond Scam.

Even if we ignore the agricultural proposals of growing crops on the garbage disposed landfills on the sea coast, the project is destined to fail. As a mechanical Engineer, Prof. De Silva would know that the slow but incessant effect of tides, currents etc., as well as the tremendously variable dynamic loads from waves in monsoonal and inter-monsoonal times will take their toll on the garbage wall. Only strong well-designed breakwalls (aka breakwaters) can face such furious power. Anyone driving along the southern coastal strip of Sri Lanka will know that efforts at controlling sea erosion along those coasts have failed. So, what chance has the proposed wall of garbage against the power and fury of the ocean?

It is most likely that any such garbage-packed wall will disintegrate within a year and spew garbage all along the world famous golden coasts of Sri Lanka. In addition to the irreparable pollution to its own fishery, tourism, its marine-coastal ecosystem, many international treaties of the sea will be contravened.

In Canada and many other countries where the integrity of marine ecosystems have come to be greatly valued, what can be disposed in the ocean are strictly controlled. They are listed in Schedule 5 of the Canadian Environmental Protections act. Some examples of acceptable disposal at sea are:

1. the sand at the bottom of a channel is dredged and disposed at sea to help control rising water levels and increase ship safety.

2. a fish plant in a remote location disposes the fish waste (flesh, skin, bones, entrails, shells etc.) at sea as there is no other option

3. a ship is cleaned and sunk at sea when no ship recycling facility is available

4. a rock slide occurs on a remote road along the coast, and the rocks are disposed of at sea for efficiency in cleaning up the road when the rocks are not a potential risk for the marine environment

5. in a remote rural location, where there is no practical alternative, the offal from disease-free muskox is placed on the ice and allowed to fall into the sea during the spring melt.

Item numbers 2 and 5 show that no rotting matter can be lightly disposed off in the sea.

Mr. Ranil Wickremasinghe severely criticized the Chinese port city project in the run up to the 2015 January election when the Yahapalanites won. But the addition of rubble and sand to the sea in the construction of the port city is not as serious as adding a wall of rotting garbage along the coast, or the ecological dangers of oil exploration in the Mannar basin.

The Yahapalanaites stopped the port city when they came to power; then re-authorized it and even paid heavy penalties for delaying the project. However, perhaps some individuals profited handsomely in the process. Now the port city is being built, giving an opportunity for ecologists who complained about the project to gather daily data on the environmental impact of such construction. There is a dearth of information, especially for tropical waters regarding such projects.

(The author pioneered courses in Food Science and environmental studies during his tenure as a Vice Chancellor and Professor of Chemistry at Vidyodaya which is today’s SJP university. He is currently a Professor of Physics at the University of Montreal, and works for the National Research Council of Canada.)