The rivers and canals in Jakarta run black and putrid from the garbage that builds up along their edges. So clogged are they with waste that they often can not carry rainwater away from the city, leaving it flooded.
Jakarta residents are bracing for the floods expected throughout the November to February rainy season. While the heavy rains have always filled the streets and waterways, the city's residents themselves worsen the problem.
Jakarta's sanitation agency says the city's residents produce 6,300 tons of garbage a day. Only five percent of that ends up being processed for reuse.
Much of the rest ends up in poorly maintained dump sites, thrown into the streets or tossed into rivers and canals. And when the rains come, that trash clogs drains and dams waterways, sending even more water into streets and homes.
Fitrian Ardiansyah is the climate and energy program director at the environment organization WWF. He says solving the problem requires residents to reduce consumption and increase recycling.
"It means the biggest component of trash in Jakarta is really being dumped in the river bodies or the sewers. So it's really one of the biggest challenges in Jakarta, and it's not only associated with the infrastructure but also the behaviors of Jakarta," he said.
Household waste makes up nearly 60 percent of the city's trash, and most of it can be reused. But many residents in Asia's megacities simply toss their trash aside. In cities like Jakarta, where new dump sites are scarce, curbing waste output has become a priority of environmental advocacy groups.
The WWF considers Jakarta to be one of the Asian cities most at risk from the effects of climate change. As rising global temperatures raise sea levels, the low-lying city is increasingly vulnerable to floods - a situation made worse by the rapidly growing population and Jakarta's mounds of trash.
Jakarta Green Monster is a group focused on saving the city's one remaining wetland area. It recently held a volunteer clean-up day to educate people about the importance of cutting the use of materials such as plastic bags and bottles, which threaten Jakarta's natural ecosystems.
Hendra Aquan is the group's community development coordinator. At the clean-up day, he said trash that flows in from the Ciliwung River gets stuck in the mangroves, which protect Jakarta from flooding, destroying the tree roots as well as the habitats of native birds.
"There's so many kinds of rubbish, like styrofoam, plastic bags. We've found sofas and sandals and many others. So this is like a one-stop shopping area for rubbish," he said.
To help spread its message, Jakarta Green Monster works with companies looking to expand their community activities. Dedi Wahyudi works for Kellogg Brown and Root, a U.S. engineering and construction company. At the wetland clean-up day, he said the effort made him more aware of what happens to his garbage.
"We have to continue this event more regularly. Maybe every two months. We start with ourselves, and the others maybe will follow us," he said.
After two hours of pulling trash from the wetland area, participants share soft drinks and listen to the words of Efek Rumah Kaca, or Greenhouse Effect, a band helping promote awareness of the effect of climate change in Jakarta. Around 500 kilograms of trash were hauled away to the city's main 125-hectare dump, but if the sanitation department's predictions pan out, it will not be long before it is back.
Next month, officials from around the world gather in Copenhagen to negotiate an agreement to reduce global warming and help countries cope with rising temperatures. It is not clear, however, if the negotiators will agree on binding commitments to cut emissions of greenhouse gases, such as carbon dioxide, which are thought to contribute to warming.