Wednesday, 1 October 2014 00:00
Recently, the Sri Lankan Government announced that the Cabinet has approved an environmentally-acceptable and economically-feasible solid waste management project to dispose of the solid waste collected in Colombo City and its suburbs.
The proposal envisages the transport of collected garbage by train to a sanitary land-fill in Arukkalu in Puttalam District, to be buried in existing pits formed by the extraction of lime for the Puttalam cement factory. In addition, part of the waste would be used as fuel for the cement factory; what percentages would be used in each section was not indicated.
Over the past years, residents of Meetotamulla and Kolonnawa took to the streets with their struggle against the Colombo Municipality, demanding the removal of garbage. People were unable to live next to the stinking, disease-causing mountain of garbage which had been disturbing them for years. The Mayor of the Colombo Municipal Council informed that only 30 families were still living in the area and that 101 families had been evacuated. Over Rs. 10 million has been allocated to provide a monthly allowance as house rent for the evacuated families.
Colombo – the biggest polluter in the country – until a few years ago remained a stinking mess with its streets strewn with trash and the Beira Lake used as a dumping yard for the slums occupying the lake edge; today, it boasts of having rid itself of garbage heaps.
The credit for the transformation should go to the Defence Ministry, which stepped in to supervise trash collection and street cleaning, along with cracking down on public who dumped refuse in public places. However, the CMC’s collected refuse remain dumped at different locations, while the former Bloemendahl garbage dump has been abandoned and shifted to Meethotamulla.
According to a survey conducted in 2005, cities collecting garbage exceeding 100 tons per day are:
Colombo: 1,257 tons
Gampaha: 313 tons
Kandy: 145 tons
Batticaloa: 119 tons
Galle: 103 tons
Total collection of garbage per day in Sri Lanka was estimated to be 2,840 tons with 58% originating from the Western Province. Today, collection would be much higher.
The collection of garbage is only the basic problem; the bigger challenge is to dispose of it once collected. A few local government councils have addressed the issue, with the Balangoda Urban Council in Ratnapura District paving the way, and Bandaragama and Horana Councils along with some others making some progress, where garbage is recycled in an eco-friendly manner.
Disposal of collected garbage
The disposal of collected garbage is not easy; decades ago the CMC used a number of incinerators to burn the garbage. However, the incinerators could only handle small quantities and were discontinued due to public protests, as incinerating of garbage is expensive and also leads to release of toxic gases and smoke, resulting in atmospheric pollution. Thereafter, the CMC resorted to dumping garbage into low-lying grounds, a practice carried out to date. In addition to the CMC garbage heaps, the garbage mountain at Karadiyana near Boralesgamuwa in the Kesbewa Urban Council and the one in Minneriya which has been invaded by foraging elephants have made it into the news.
Over the past few decades, the newspapers announced a number of proposals to generate power by burning garbage as is done in developed countries, but none materialised. Now we are being told that Sri Lanka’s garbage contains 70 to 80% vegetable matter and are unsuitable for burning for power generation.
Creation of garbage
Anything thrown away during day-to-day life and considered unnecessary becomes garbage. In Sri Lanka each house generates 0.7 to 1 kg of garbage a day, comprising of 80-90% organic matters, which are biologically degradable, along with varying components of paper, plastic, glass, metal and e-waste. The components vary from urban to rural and even on a day-to-day basis. In spacious gardens leaves from trees and papers are burned and kitchen waste is passed over to the local authority.
The garbage produced by small and large hotels, vegetable shops in markets and fish, beef and chicken stalls in markets decompose fast, but produce an unpleasant smell. In addition, waste from hospitals and nursing homes and barber shops need disposal, as do construction waste and resulting demolitions due to alterations to buildings and houses. In Colombo there are persons who undertake to dispose these for a fee, but only dump them in unauthorised properties on the sly.
Garbage is a nuisance
Decades ago people’s waste got decomposed in their gardens; however with the changing lifestyles, cooking moved away from firewood and biodegradable wrappings turned into polythene and household plastic items.
Garbage, while clogging drains locally, creates health hazards for the people who live close to garbage dumping grounds, degrades the aesthetic value of the environment and results in socioeconomic issues due to lowering property values.
Decomposing garbage results in emission of air pollutants like methane, ammonia, hydrogen sulphide and other offensive gases and leads to global warming, and also encourages stray cats, dogs, rats and mosquitoes. Garbage dumps in Polonnaruwa have attracted wildlife such as deer and elephants.
Leachate formed during the decomposing process seeps through the ground or is washed off joining runoff, creating surface and ground water pollution.
Legal responsibility of garbage
The National Environmental Act (NEA) of 1980 was superseded by a National Policy for Solid Waste Management (SWM) prepared in 2007 “to ensure integrated, economically-feasible and environmentally-sound solid waste management practices for the country at national, provincial and Local Authority level”. An activity sprung from the National Policy is the setting up of the ‘Pilisaru Program’ in 2008, to solve the solid waste problem at the national level.
The ‘Pilisaru Project’ of the Central Environmental Authority (CEA) encourages the concept of reusing collected garbage before final disposal. With technical and financial assistance on SWM to the local authorities, CEA is empowered to take legal action against local authorities who do not manage their solid waste properly.
The best way to discourage production of garbage is by encouraging people to handle their own garbage without being a burden to the local authority. This could be named “green housing” and can be encouraged by giving credit with a percentage reduction of rates payable by them.
Collection and transport
Currently, garbage is collected and transported by the local authorities. The mode of transport varies and comprises hand carts, two-wheel tractors with trailers, four-wheel tractors with trailers, compactor trailers (used mostly in Colombo), and a few skip trailers used in Colombo MC.
The cost of collection and transport is the heaviest cost in the disposal of garbage, especially considering the inefficiencies shown in the administration of street labour.
Garbage transport to Puttalam
At present 700 metric tons of solid waste is collected in Colombo each day, while 1,200 metric tons are collected from other urbanised local authorities such as Nugegoda, Kaduwela, Moratuwa, Ratmalana, Mt. Lavinia, Ja-Ela and Kolonnawa. The garbage is to be transported by train from a transfer station at Meethotamulla to the proposed landfill at Aruakkalu, north of Puttalam.
It is claimed that for the proposed disposal system, the Railway Department has completed the designs of the rail transportation system and the preparation of specifications for locomotives and rolling stocks. The Environmental Impact Assessment (EIA) report of the project has been completed. The total cost of the project is expected to be $ 107 million (Rs. 14 billion).
The above is only the capital cost of the basic proposal; transport from the collecting towns to the collecting point, from Aruakkalu station to the dumping location and the running cost of the system would amount to a substantial sum.
Disposal in Puttalam
The garbage transported to Puttalam is expected to be buried in voids created by excavation of limestone and covered with soil. With respect for disposal by burning in the cement factory, local garbage with 70-80% vegetable matter is considered unsuitable for burning for thermal energy, but burning at high temperature would avoid pollutants.
A better method would be to transport the minimum quantity to Puttalam and dispose of most of the trash locally, possibly by composting.
Disagreement by CEA
The acceptance of the Environmental Impact Assessment (EIA) for the Puttalam garbage dump has been disputed by the Director General of the Central Environmental Authority. According to environmental groups, apart from approval, the EIA report is yet to be prepared. Prior to the EIA, a Terms of Reference (TOR) indicating guidelines for the project should be prepared by the UDA, the proponent along with North Western Environment Authority. Accordingly, EIA acceptance and the project commencement could be years away.
Project implementation necessitates establishing a railway disposal system including extension of lines, stations at Meetotamulla and at Puttalam and purchase of rolling stock, and transport of garbage after unloading need to be attended.
When the garbage transport system is in place, improving the handling capability to reach the total collection would take a considerable amount of time. But then how about the current garbage mountains at Meetotamulla, Grandpass and Karadiyana, against which the public has been fighting? A more prudent method would be to begin disposal of garbage by composting, commencing immediately.
In nature’s way of composting, leaves falling to the ground are soon composted, returning their nutrients to the trees which bore them. Nature has been making compost since prior to the appearance of primitive life on this planet. Humans, animals, insects and plants are interconnected in a complex cycle along with air, water and soil, minerals with natural resources contributing their waste and eventually their bodies helping to grow food, so that more of their kind may multiply and prosper. Compost is more than a fertiliser; it acts as a soil conditioner.
Local garbage contains a high percentage (70 to 80%) of vegetable matter and could be converted into compost. Of the local government units, the Solid Waste Management Unit run by the Balangoda Urban Council has been the torchbearer in the field, operating since 2003. They have been successful in the sale of their final product – compost as well as by-products. The Council was awarded the National Productivity Award in 2005.
Their way of making compost fertiliser is the open window method:
The graded waste is heaped into piles (height five feet and width 12 feet)
On dry days the pile is kept moist, the resulting bacteria action causes decomposition and the temperature rises.
The piles start distilling waste water which is acidic and is guided to a separate tank.
The waste water is mixed with clean water and added back to the waste pile.
These piles are left alone for about six weeks.
After six weeks, the piles are turned over for airing.
Waste water is sprayed over the turned piles.
After a further two weeks the decayed waste is turned over and mixed.
After the second turning the compost pile is left to dry to reduce moisture to 8%.
The decomposed product is graded by separating non-decayed materials from compost.
The produced compost is enriched by mixing with paddy husk charcoal, obtained by controlled burning of paddy husk, a rich source of potassium.
Disposal of end-product
The Balangoda Urban Council has been lucky in that they were able to dispose their products amongst the neighbouring farming community who were used to purchasing cow dung. However, if the CMC were to follow the same path, it would face difficulties in disposing of its compost, unless revolutionary uses could be introduced.
Compost nutritional value
The NPK (Nitrogen:Phosphorous:Potassium) values for a typical compost is around 0.5-0.5-0.5, which compares very poorly against the imported fertilisers currently used by the farmers. At the user level, compost contains adequate levels of the various mineral nutrients but can be low in trace elements.
NPK values are not the only consideration for plant nutrition; it also involves the processing of minerals and other nutrients by the soil organisms. The compost is the best all-round source of organic material as a nutrient for soil organisms. The composting process has ‘pre-digested’ the material, making it easier for soil organisms to assimilate it as nutrients.
Most garden soils are low in organic content. Feeding the garden means feeding the soil organisms and compost is an excellent source of these nutrients. Compost improves soil structure and drainage; organic materials convert slow-draining clayey soils to drain faster and fast-draining sandy soils to drain slower and thus reduces loss of soil moisture.
Disposal of compost
If all the garbage collected in Colombo were to be converted into compost, the result would be a mountain of compost, the usage of which needs to be kept with quantum of composting. As such, revolutionary ways of usage of compost need to be found.
One way would be organic gardening which is becoming popular, with organic products currently commanding premium prices. Of the paddy lands that were taken over during the planning of Parliamentary Complex in Madiwela, farmers were allowed to cultivate 76 acres under organic farming, without using pesticides, weed-killers or chemical fertiliser.
Colombo and Gampaha Districts, where most garbage originates, possess large acreages under paddy fields, of which nearly 80% are uncultivated. Cultivation of these lands using compost would consume large quantities of compost. In paddy cultivation, yields in the Colombo District are the lowest in the country, discouraging farmers. But cultivation of indigenous varieties of rice, which give low yields but command higher market prices, would be possible. A better possibility lies in the cultivation of grass as a fodder for cattle for milk production.
A major proportion of the population of the country uses imported or locally-produced powdered milk. A litre packet of milk in the market sells at around Rs. 170, while the milk farmer receives only a third of this value. If dairy farming is popularised, with cattle-fed fodder produced in uncultivated paddy lands, the populace in Colombo and Gampaha Districts could be offered fresh milk at a lower price.
Until the 1970s, the low lying lands around Nawala and Pitakotte were grasslands that fed a large number of small dairy farms who fulfilled milk requirements of city residents. Lately local governments have discouraged cattle rearing, and such farms were forced to close down. Today some small dairy farmers still continue outside city limits; however, most such farmers do not have grasslands of their own. Thus, motorists come across these small herds roaming the streets and eating garbage. Instead, dairy farming could be popularised again in lands away from cities; however, moving forward would require a well-coordinated program.
Over 80% of paddy fields in Colombo and Gampaha Districts remain uncultivated, with cultivation percentages improving when the Government announces taking over of uncultivated lands. The country already possesses legislation for takeover of such lands and the landowners need to be pressurised to cultivate their paddy lands, using compost supplied at a nominal price.
Consumers tend to avoid consuming milk from small farmers due to concerns of hygiene; small farms with a few milking cows, milked by hand, using unclean containers comes to mind. For fresh milk to be acceptable to the consumer, such farming units should convert to mechanised milking. According to the internet, mechanised milking machine prices start from $ 500 or Rs. 65,000 duty free, and should not be beyond a prospective small investor.
The proposed dairies would be:
Current large milk producers who can start pilot units in each district
Farmers who already have few cattle
Current land owners wishing to commence dairying
Paddy land owners should be encouraged to re-cultivate their idling lands with paddy, indigenous varieties of rice, vegetables or grasslands as fodder, all using compost. The farmers could supply grass to dairies on a contract basis, using small machinery for land preparation and harvesting. However, each dairy would need grasslands of their own for food security. The Government could supply compost at a nominal cost that would cover packing and transport to encourage farmers.
Cattle for starting up farmers
The Government has already announced plans to import large herds of cattle for the existing farms and the Kandakadu farm run by the Army. The cattle from up-country or the dry-zone may not suit wet conditions in Colombo and Gampaha, and may have to come from Horana or Labuduwa farm near Galle or similar locations. Experienced companies could import their own requirements; local farmers and new organisations could get second generation stock from Government farms.
The Government needs to commence training courses for prospective entrepreneurs from farm workers, supervisors and managerial levels on dairy farming. With a little encouragement in the form of low import duties, the private sector would import and set up maintenance for farm and milking machinery.
The distribution of produced milk could be undertaken by existing companies, new ventures or even small farmers themselves, convincing the consumers of their good hygienic practices. The current selling price of milk is well over thrice the price paid to the producers, due to packing, storage, transport and retailing costs. With lower selling prices, small producers could carve out niche markets for the disposal of fresh milk in the locality, which would serve both consumer and the producer.
The way forward
The Government’s proposal to solve the problem by transporting garbage to Puttalam is years away, considering that environmental approval has not even been requested yet. If the Government announces in the next Budget the policy acceptance of garbage converting to compost and the offer of subsidised compost for paddy, vegetable and fodder cultivation in paddy fields along with incentives for cattle rearing and milk production with reduced duty on milking machines and other needs, paddy land owners would respond positively.
If the Government takes such a stand, the Karadiyana garbage dump could begin to produce compost almost immediately and farmers can be issued with compost. The existing small cattle owners could be helped first by allocating lands for fodder cultivation. Lands left uncultivated for over a long period can be acquired first and offered to investors, which would be an eye-opener for others. Progress would depend on the supply of cattle to prospective small-time investors, while larger organisations require only Government policy and tax incentives.
The proper implementation of proposals would convert garbage from a liability into an asset. Better utilisation of abandoned paddy fields would give an income to owners and create employment, while supplying the public with lower cost fresh milk would ensure that the country become self-sufficient in milk.
The cost of providing subsidised compost would be cheaper than the cost of building infrastructure and transporting garbage to burying locations. The cost of transport would be a waste, whereas improved cultivation practices would create self-sustaining farmers.
(The writer is a Chartered Civil Engineer graduated from Peradeniya University and has been employed in Sri Lanka and abroad. He was General Manager of State Engineering Corporation of Sri Lanka. He can be contacted on [email protected])