Brazil is immersed in the World Cup, but its biggest test is yet to come. With the clock ticking down to August 2016, when Rio de Janeiro will host the Summer Olympics, the country has big promises to live up to.

As part of its winning Olympic bid in 2009, Rio pledged to host “Green Games for a Blue Planet.” Specifically, the city of 6.3 million said it would use clean energy, clear the city’s clogged streets, preserve its natural spaces, and upgrade its “favelas”—poor neighborhoods full of ad-hoc infrastructure—to more-urbanized spaces with functioning utilities, public transportation, and other amenities.

But five years later, Rio is far from on track to meeting those lofty standards, and it appears near certain they won’t be met in time for the opening ceremonies.

The bid for the 2016 games played up the potential for overhauling Rio’s notoriously traffic-choked roads by adding trains, buses, and public bike-share programs. The highlight was to be a transportation ring of light rail and buses downtown and subways to connect to farther-off areas where some of the Olympic events will be held. Getting people out of cars would not only free up the streets during the games but would slash pollution.

Cost overruns and construction problems have either delayed or scuttled most of those projects. Last week, a report from the national auditing office found that nearly all of the public-works projects are behind schedule and the costs have increased between 7 and 122 percent above their original forecast. Some sites haven’t even broken ground, and construction at Deodoro, the venue which will host events like BMX biking and rugby, won’t start until later this year.

A more literal example can be found in Guanabara Bay, the site of the Olympic sailing competition. Rio had promised to clean up the water—which is fouled with debris, sewage, and even fish corpses—but Mayor Eduardo Paes conceded last month that goal wouldn’t be met.

“I am sorry that we didn’t use the games to get Guanabara Bay completely clean, but that wasn’t for the Olympic Games—that was for us,” he said.

During an April visit, International Olympic Committee Vice President John Coates said during an April visit that the preparations were “the worst” he had seen.

Rio is far from the only host of an international sporting event to overpromise and under-deliver. The possibility that any such so-called mega-event could be sustainable is a long shot at best, but that hasn’t stopped countless cities from making the promise.

The optimistic environmental promises are a product of a misaligned incentive system. Countries’ hosting bids are greatly bolstered when they include major green pledges. But once the event is awarded, there are few, if any, consequences for countries if they don’t follow through.

“The IOC and FIFA understand that one of the big objections to these mega-events is that they destroy the environment, so they put in these requirements. But then what do they do?” said Jay Coakley, professor emeritus at University of Colorado (Colorado Springs). “They can’t enforce them. There’s no accountability after the fact.”

Plus, he added, the high cost of building and hosting the events leaves little money in the end for projects that were extraneous to the games themselves.

“If the money hasn’t been allocated up front, what can happen is a city or region goes so deeply into debt and there’s so little money and energy left to complete those projects,” said Coakley, who has studied the impact of mega-events. “Sustainability goals usually get shoved to the side. It’s difficult to have an event with the footprint of the Olympics and make any improvements that have a net sustainability impact.”

The problem of unmet sustainability promises also plagues Brazil’s hosting of the World Cup, where all 12 host cities talked up varying degrees of improvements. As the $10 billion-plus preparations for the Cup ran increasingly behind schedule and over budget, attention turned away from legacy projects and onto triage for the stadiums.

The northern city of Natal, for example, completed just one of seven planned transportation upgrades and ended up nixing three entirely. A high-speed rail line between Sao Paulo and Rio that was to be functional during the Cup never even put out bids. And solar panels meant to power several stadiums never went up.

“Several of the promises made at the candidacy dossier will not be met,” said Alberto Murray-Neto, a former member of the Brazilian Olympic Committee.

The trend of broken promises is not new, and it appears likely to continue in upcoming Olympics and World Cups.

In hosting the 2012 Summer Games, London promised the greenest Olympics ever through the use of clean energy and recycled materials, while also creating a monitoring system that could be used for future projects. Ahead of the Sochi Winter Games this year, Russia established new building codes.

The London games did successfully reduce emissions during construction and built a well-regarded transportation hub to promote public transit, but a report from World Wildlife Fund and BioRegional said that organizers failed to do enough to meet their energy promises.

In Sochi, environmentalists said that Russia’s construction practices damaged the region’s natural ecosystems, and the Associated Press found an illegal landfill during construction—evidence that the games weren’t zero-waste as promised.

In 2022, Qatar will host World Cup in what is likely to be blistering heat, but the country has promised carbon-neutral air conditioning thanks to an “absorption chilling” process that relies on solar power.

The fact that Rio won’t meet all of its goals, however, doesn’t mean the whole event will be an environmental wash for the city. Rio already relies heavily on hydroelectric power and plans to integrate more solar into the Olympics operations. The city has invested in improving its water and sewage systems, and stadiums were designed to naturally reduce their energy consumption by taking advantage of natural light and incorporating solar power. At least 70 percent of the Olympics infrastructure will be used after the 2016 games are over, such as the conversion of the Olympic Village to condos.

Contrast that with the “white elephants,” or the stadiums and structures that sit unused and take up land, like the barren Birds Nest in Beijing or the 2004 Olympic Grounds in Athens—which sit abandoned to weeds and stray dogs. (There is concern that several Brazilian World Cup stadiums could end up empty and unused in cities without soccer teams.)

Still, most analysts see the biggest gains from the so-called legacy projects, the long-lasting urban upgrades that could fulfill Paes’s promise that the games would overhaul the city. The construction delays mean that the city may fall short of the successful changes made after games in Barcelona or Tokyo, which used the 1964 games as a catalyst for a bullet-train system.

Those projects are a big selling point for both citizens and the world, and can be a way to justify the massive cost of hosting the games (remember, almost no city comes out ahead from the Olympics, even with the influx of tourists). But Brazil has seen massive unrest over the spending on the sporting events, which citizens say could be better used on health care or education.

But Murray-Neto, whose grandfather served in both the Brazilian Olympics Committee and the IOC, said using the money to cover routine costs squanders not just the potential but the promise of the Olympic games.

“I think that Olympism is the union of sports, culture, and environment,” he said in an email. “Therefore, I see it as an obligation of the Olympic hosting city to, among other … things, improve its environmental conditions. Not only for the games, but as a legacy for the city.”