Residents of Mexico City face fines for failing to separate their trash as pressure mounts for the closure of the main, overweight, landfill in one of the world's largest cities.
Garbage disputes are nothing new in the sprawling, polluted urban area of some 20 million inhabitants, but as the trash piles up so do fears of long-term health and environmental damage.
Without taking into account the greater urban area, Mexico City produces more than 12,000 tonnes of waste every day.
"The aim should be zero waste in Mexico City because there's no land, there's nowhere foreseen to deposit waste in these quantities," said Ramon Ojeda Mestre, secretary general of the International Court of Environmental Arbitrage, involved in the city's latest trash debate.
Each citizen now creates a daily average of 1.41 kilos (3.1 pounds) of waste, compared with 800 grams (1.8 pounds) 20 years ago.
Eco-minded Mexico City mayor Marcelo Ebrard, the leftist Democratic Revolutionary Party, wants citizens to be more responsible for their trash, by separating organic and non-organic waste.
"We're going to carry out a very big campaign, we'll reward people who do things well, we'll sanction those who do them badly," Ebrard told AFP.
The campaign gives the city's 16 districts 150 days, from the start of the year, to apply a new waste separation law.
Citizens who fail to separate their waste could face fines of up to 7,000 pesos (almost 500 dollars), or up to one million pesos for dumping building waste in parks or conservation areas.
"The biggest challenge is to change some habits; not all of them but some of them," Ebrard said.
Recycling has existed here for decades, however, but with economic, not environmental, motives and many citizens who do not pay taxes for trash collection see no reason for change.
Chilangos, as Mexico City residents are known, simply mix all their trash together and pay tips to unsalaried garbage workers to collect the bags and carry out the separation themselves, selling on useful bits for profit.
Hundreds of other waste workers carry out further often dangerous recycling among toxic materials on rubbish dumps, including on the massive Bordo Poniente landfill in eastern Mexico City, festering in a political dispute over its closure, which was postponed last July and again this month.
Mexico City authorities who manage it are seeking more time to find what they say will be a more ecologically friendly alternative. But federal authorities, from the rival National Action Party and who own the land it sits on, seek a rapid shutdown of the near-full dump, citing environmental concerns.
Ebrard plans several new high-tech waste treatment sites to replace the landfill, but so far only one site has been found and it will not be ready for two years.
He also plans to transform the bio-gas it emits into electric energy and has attracted a pledge to help from the Bill Clinton foundation.
"A precipitated closure could create serious environmental damage," Martha Delgado, the city's environment secretary, told AFP. "We really want an in-depth solution to the problem. All we need is more time."
But federal authorities say the city authorities want to avoid payment of an estimated one billion pesos to shut Bordo Poniente safely and for new landfills to replace it.
"The problem is that they have to pay and they're not ready to invest adequately in waste management," charged Mauricio Limon Aguirre, a top federal environment official.
"It's not our responsibility," he added.
Observers blame both sides for refusing to help solve the problem, while the dump further pollutes its surroundings as the dispute drags on.
"It's contaminating the air, the ground, the underground water," said Ojeda Mestre, who has threatened to take both governments to international courts in the matter.
Neither government has carried out adequate campaigns against the generation of rubbish, or for waste separation, despite previous laws, Ojeda Mestre added.
Ebrard, however, said his new campaign would make a long-term difference.
Starting this year, the city will force big businesses to pay for their trash collection.
"If you have a chain like Walmart, why don't they pay for waste? We have to start with the big waste generators," Ebrard said.
"What will remain from what we've done is changes in society's habits."
But many are skeptical at a time of belt-tightening in other areas amid growing evidence the financial crisis will hit hard below the US border.
So far, there are few signs of equipment for citizens to use to separate their trash, or of sites or new rubbish trucks to receive it.
Jorge, 38, has worked on a rubbish truck in the central Cuauhtemoc district for 18 years.
Separating orange skins from cardboard boxes into plastic bags on the back of his truck, he said past campaigns had failed to produce changes.
"Citizens haven't responded in the way they were hoping for. There isn't a culture for that," he said.
His eyes lit up as he described planned modern replacements for many of the city's more than 2,000 garbage trucks.
But he added: "I don't think the government has the money."