Many sports fans attending events at the Air Canada Centre apparently don’t flush after using the washroom urinals.

Let’s hope they at least wash their hands.

The lack of flushing was one unexpected finding after management decided to install automated flushing devices on facility urinals.

The goal was to reduce water consumption. But having the devices flush less frequently on behalf of porcelain patrons actually had the reverse effect: more water was being consumed.

After a bit of head scratching, it became clear that the male sports fan’s lack of arena hygiene was already minimizing water use. Who knew?

The law of unintended consequences does often assert itself when businesses attempt to “green” their operations, but in the case of the Air Canada Centre such outcomes are the exception.

A report this week from the Washington, D.C.-based Natural Resources Defense Council (NRDC) has named the home of the Maple Leafs and Raptors one of the 16 most progressive sports venues when it comes to reducing environmental impacts.

“Certainly much work remains to be done, but it is heartening to note that teams and leagues across North America are implementing meaningful changes and educating tens of millions of fans about environmental stewardship,” according to the report, pointing out that much of this work is being done behind the scenes and out of the spotlight.

The council notes that “going green is savvy business, enabling teams and venues to cut operating costs, strengthen corporate branding, attract sponsors and enhance the fan experience.”

It wasn’t until 2007 that the Air Canada Centre really turned its attention to the opportunity. That’s when management hired Bryan Leslie, who had previous experience “greening” a military base, as its new director of building operations.

His mission had high-level support from within Maple Leaf Sports & Entertainment, owner of the arena, the Leafs and the Raptors. Both board directors and senior management were engaged and interested from the beginning, and Leslie was given a $5 million budget to execute on an ambitious environmental plan.

The Star’s Chris Zelkovich noted some of these initiatives back in 2009, including the use of deep-lake water cooling, heat recovery systems, room occupancy sensors and lighting controls, and the implementation of a comprehensive recycling plan, which didn’t exist prior to 2007.

But with the five-year initiative near complete, the NRDC highlights some impressive accomplishments:

Between 2007 and 2011 the arena has reduced its carbon emissions by 30 per cent;

Upgrading of lighting to more efficient LED and T8 technology has reduced annual energy use by 1.34 million kilowatt-hours, roughly the same amount of electricity consumed each year by 120 average-sized homes in the GTA;

Waste destined for landfill has been reduced by 74 per cent compared to 2007 by recycling, composting and reducing the inputs that can lead to waste. The goal is to divert 95 per cent away from landfills by the end of next year;

Chemicals are no longer used in ice-making or painting the ice on the rink. This has been replaced by a reverse-osmosis water purification system and non-toxic water-based paints.

Leslie, in the NRDC report, makes clear that what the Air Canada Centre is doing is becoming increasingly common in the sports world.

Note that the Bell Centre, home to the Montreal Canadiens, was also highlighted in the report as one of the 16 leading “green” professional sports venues. And even though the Rogers Centre wasn’t included in the group, improvements there may very well have inspired MLSE management.

Back in 2007, for example, I wrote about how the Rogers Centre was in the middle of a three-year energy efficiency retrofit project that aimed to cut electricity use by 33 per cent, using a combination of automated and sensor-based lighting technologies and other conservation measures.

The leagues, with support from the non-profit Green Sports Alliance – a group founded and funded by billionaire Paul Allen, co-founder of Microsoft and himself an owner of two professional sports teams—are also pushing it.

“We have discussions monthly with the NHL, and all the arenas come to the table with their ideas,” Leslie said. “Amazing stuff is coming out now, and as much as I’m proud of what we’ve done, I see that there are so many new ideas out there.”

One criticism of the NRDC report is that it doesn’t tell us the size of professional sports’ environmental footprint. Individual stadium or arena efforts, while impressive on their own, may just be scratching the surface of wastefulness and excess that has existed industry-wide.

But the true value of league, team and venue initiatives may be educational in nature. What they have is a captive audience of tens of millions, and through their own actions they can help influence the personal actions of sports fans.

And, as the report points out, “Perhaps no other industry is better suited to confirm that environmental stewardship has become a mainstream, non-partisan issue.”

Tyler Hamilton, author of Mad Like Tesla, writes weekly about green energy and clean technologies.