TORONTO - With just a few seconds of effort, anyone can easily shrink their impact on the environment by telling Canada Post to stop delivering junk mail -- but only two per cent of Canadian homes have done it.

Canada Post says it's because people want to get flyers and ads delivered at their door. Vancouver's Beth Ringdahl begs to differ.

Ringdahl's website, www.reddotcampaign.ca, spells out a simple two-step process to block junk mail: It's as easy as filling out a downloaded form and leaving a note on your mailbox.

For more than a decade, Canada Post has been quietly acknowledging such requests, halting junk mail deliveries and marking a homeowner's internal file with a red dot -- hence the name of Ringdahl's campaign.

The website's only been up and running for a couple of weeks, but word is spreading fast.

Ringdahl says the letter has been downloaded more than 2,300 times, her Facebook group has swelled to more than 850 members and grateful visitors are e-mailing everyone they know about the site.

"People are really happy to learn about a way they can reduce the waste in their lives," she said.

"(The campaign) is like a friendly reminder saying, 'Hey guys, here's something you can do that will take away some clutter and save some trees."'

Canada Post spokeswoman Lillian Au said Ringdahl's campaign is unnecessary -- Canadians, she says, have known for years about the opt-out option.

"It has been in place since 1997, so we feel that we've done a good job and people know that they have that right," Au said.

Au acknowledged that unaddressed advertising mail is one of Canada Post's fastest growing revenue streams -- it brought in $339 million in 2006, up 14.4 per cent from 2005 - and helps keep costs down for consumers, while allowing small businesses to advertise in an affordable way.

Almost all of the promotional mail is recyclable and printed on recycled paper, she added.

But Au also confirmed Ringdahl's theory that marketers would likely end up printing fewer flyers if there were fewer homes that received the junk mail.

"We make regular updates to our mailers, who can adjust the amount of material being printed so they don't print excess flyers," Au said.

Ringdahl said she never intended to do battle with Canada Post, and instead applauds its policy. She's just trying to do a better job promoting it.

"I really think this is a world-class system that they have set up, and I don't want it to be a cop out (for) the individual, saying, 'Oh, Canada Post didn't tell me how to do this."'

Her next goal is to target homeowners who don't speak or understand English so the campaign's reach grows even further.

Valerie Langer of the environmental group Forest Ethics applauded the campaign, which she said was a mystery to even those who are working to protect Canadian forests.

"It's giving people the kind of information that starts them thinking and allows them to act in a way that conserves paper and therefore forests," Langer said.

Langer herself just recently learned about opting out, she added.

If homeowners decide they do want to stop receiving junk mail, Au said printing out the letter on Ringdahl's website isn't necessary; a note on the mailbox -- inside the door if the box is in an apartment building or condo -- will suffice.

A warning, however: stopping junk mail also halts delivery of municipal-service notices such as town hall meeting announcements and snow removal and garbage pickup schedules, Au said.