Thimphu grapples with mounting waste
About 51 metric tonnes (MT) of wet and dry waste from the Thimphu thromde area is dumped every day at the Memelakha landfill, located 12 kilometres from the city.
The amount of waste going to the landfill daily is after the closure of the compost plant in Serbithang, which happened since July 2015. This is six times more than the eight MT of daily waste the landfill was built for in 1994.
The lifespan of the landfill, which was designed and constructed to last 10 years, expired 13 years ago.
Thimphu Thrompon Kinlay Dorjee said dry waste is dumped at the upper side of the landfill and the wet waste is dumped in a garbage pit below.
“During rainy days when vehicles are not able to reach the upper side of the landfill, the waste could be dumped at the lower pit,” the thrompon said. “Until we set up a compost or a bio-gas plant, it is difficult to monitor whether the different waste are dumped together or separately at the landfill.”
For now, though, there is no plan to build a compost plant in any other places in the city.
Thrompon said that the thromde is planning to explore a technology either to make composting quicker or to establish a bio gas plant in Memelakha. He said that Memelakha landfill site is appropriate for wet waste since there is no settlement there and the distance is not far from the town.
“Once a mechanised compost plant to quickly decompose biodegradable waste or a bio-gas plant is established in the area, the organic waste will be consumed there where we generate gas and at the same time compost manure,” thrompon said.
He said that thromde officials visited Pune and Ahmedabad in India earlier this year where they have similar technology to compost wet waste. “We have some fund from the Indian government left for the landfill management.”
“Although we dump both kinds of waste in Memelakha, we still want residents to segregate waste at the source,” thrompon said. “If we stop segregating the waste thinking both types of waste are dumped together, people will be reluctant to have the waste segregated again.”
Thrompon said the recyclable dry waste will be recycled at the Greener Way’s transfer station in Ngabirongchu in Thimphu once it is established. The transfer station was supposed to complete this month but there is some problem with the supply of machinery. It is expected to be ready by September.
“Then on only about 10 to 15 percent of dry waste that could not be recycled and organic waste will go to the landfill,” thrompon said.
After the thromde outsourced the collection and disposal of solid waste from the city’s south and central zones to Greener Way in 2015, the firm insisted on segregation of waste at source and the compost plant saw increase in biodegradable waste. The wet waste or organic waste was disposed at the compost plant in Serbithang in Thimphu while dry waste is dumped at the Memelakha landfill.
Before the outsourcing of the waste collection and disposal to Greener Way and Clean City only about five truckloads of wet waste was dumped every month at the compost plant.
After the outsourcing of waste collection and disposal, about 100 truckloads of organic waste is dumped at the plant every month.
The compost plant built in 2008 at a cost of about Nu 8 million with the capacity to decompose 25MT of wet waste in a go took longer to decompose a chamber of wet waste.
Thrompon said that the compost plant does not have the capacity to compost the 100 truckloads of wet waste every month. As a result, all chambers at the plant used to be filled with the waste that the additional waste had to be kept outside the chambers.
“The plant was becoming another landfill,” thrompon added.
Thrompon said that the thromde received complaints from the residents in the area that the plant is filling the area with a pungent smell and huge number of flies. “I went to check and the situation was bad. So we immediately told Greener Way and Clean City to divert the biodegradable waste to Memelakha landfill.”
It took more than seven months to compost the existing waste at the plant. Until it was recently closed, the plant sold 6,475 bags of manure and made Nu 643,867 revenue.
Thimphu Thromde gave the land where the compost plant was built along with two sheds and a house to the Technical Training Institute (TTI). The area will be converted into training institute.
Thrompon said TTI shared the space with the City Bus Service near Kuensel office in Thimphu and there was problem of space so the thromde decided to give the land to TTI. “We are yet to transfer the thram to TTI.”
He added: “Even if we continue to use the compost plant with only five truckloads of organic waste every month, about 95 truckloads of waste will have to be dumped at the Memelakha landfill. Decomposing five truckloads of waste at the plant won’t make much difference to the amount of waste diverted from the landfill.”
The thromde would have to employ about five people at the plant to decompose five truckloads of waste every month if the use of the plant is continued, he said. “It is waste of resources.”