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A Breakthrough In Indoor Air Quality

By: Guest Contributor, John Dixon

Many of today’s health concerns – from allergies to asthma, to everyday health issues such as headaches and colds are often traced back to poor indoor air quality (IAQ). In fact, the EPA estimates that half of all illnesses in the U.S. today are caused by poor IAQ. Results from in-home air testing found that 96% of homes tested had at least one significant IAQ problem.

The Center for Disease Control (CDC) estimates that 2 out of 3 indoor air quality issues involve the HVAC system. An overwhelming amount of these can be traced directly to duct leakage.

Leaks in the ductwork allow surrounding air to be sucked into the system where it is then blown throughout the rest of the home. If a leak is located in a portion of the duct that runs through a dusty attic, or dirty garage, the contaminants from these spaces can be easily picked up and spread into other areas of the home. Most ductwork is hidden behind walls or in crawl spaces – areas that are often rife with dirt and other pollutants.

Leaks in the ventilation ducts are also a major catalyst for poor IAQ. Leaky ventilation ducts severely limit the effectiveness of the exhaust fan. This in turn promotes the growth of mold and mildew, and limits the elimination of smoke, odors and other air contaminants.

While some duct leaks can be repaired by hand, using special sealing tape or mastic, this old method of duct sealing can only be effective in areas where the ductwork is exposed. That leaves the majority of leaky ducts untreatable.

Faced with this dilemma, the U.S. Department of Energy, along with the EPA and others, developed a method of effectively sealing the entire duct system. Their solution is an innovative sealing technology, called aerosealing, which works from the inside of the ducts to locate and seal leaks.

Aeroseal duct sealing is applied as a mist of sealant particles that is blown into the interior of the ductwork. The microscopic-sized particles remain suspended in air until they come in contact with a leak. Here they cling to the edges of the hole, and then to other sealant particles, until the leak is completely sealed.

This unique process offers several significant advantages:

  • Accessibility. Accessing all the leaks is now simple and doesn’t require wall demolition.
  • Finding. The process automatically finds all the leaks. With traditional manual sealing, leaks can be overlooked or never identified.
  • Effectiveness. Aerosealing ductwork is 95% effective at sealing leaks. Studies found it to be as much as 60% more effective than manual sealing.

For decades, issues related to poor indoor air quality have simply gone unaddressed. Today, with increased awareness of the problem, and new innovations, that effectively tackle their root causes, we have an effective means to make major improvement to the indoor air quality of our homes.

Aeroseal animation slr

John Dixon is a freelance writer headquartered in Portland, Oregon.


The Problem With Water…

From: PJ Dore


The Problem With Water_Infographic

Zero Waste Challenge: How to make changes in your daily life to reduce waste

By: Guest Contributor, Joe Baker

It may not be the sexiest report of the year, but there were some interesting takeaways in the Environmental Protection Agency’s Municipal Solid Waste Fact Sheet, released in June 2015. “Zero waste” is a term and ideal that is growing in popularity: the idea is that a household, city or even an entire country could produce no net waste.

The United States is inching in the right direction. According to the EPA, in 2013 our per capita municipal solid waste was down by a third of a pound to 4.4 pounds per person per day since the peak in 2000. Even more exciting, recycling continued to increase, topping off at more than 34 percent—more than double the recycling rate 30 years ago.

But there’s still a lot of work to do, which is why cities and counties are trying new ideas and policies to make it easier for their communities to reduce waste.


shutterstock_156179246More communities are embracing green bins and implementing composting programs. San Francisco has required composting since 2009, and in 2014, Vermont became the first state to include mandatory composting in its Universal Recycling Law.

Composting is one of the best ways to not only reduce your waste, but also produce something valuable for your community. When food waste ends up in landfills, it’s packed so tightly, there’s not enough oxygen for it to biodegrade and improve soil quality. By contrast, compost creates a rich soil coveted by gardeners. Some programs exploit this connection, like one school composting program in East Harlem, which teaches kids to compost and then uses the product to fertilize local community gardens.

Step Up Recycling

As exciting as it is that recycling rates have doubled in the last generation, a 34 percent recycle rate means that two-thirds of waste still goes to landfills. That’s not surprising: Just 35 percent of households and 10 percent of businesses recycle. Localities have taken steps to make recycling easier, notably the popular single-stream recycling systems, in which all recyclable materials are thrown into one bin, making recycling an easier choice. Recently these systems have come under scrutiny as overzealous homeowners throw more in blue bins, resulting in high sorting costs. The challenge will be reducing these costs while still supporting policies that engender a culture of recycling. Folks at home can help by being a bit more choosy.

Plastic Bag Bans

shutterstock_181487378Plastic bag bans take waste reduction a step further: rather than come up with better ways to deal with the waste we produce, why not just make less of it in the first place? According to the Surfrider Foundation’s self-admitted incomplete list, cities in 18 states have regulated single-use plastic bags. California and Hawaii even have statewide bans. These laws inevitably stir up controversy (and, of course, a backlash from the plastics industry), but importantly they raise awareness about our culture of disposability. Plastic bags are an environmental scourge, as the Texas-sized Pacific Garbage Patch illustrates. Policies that force us to pay for disposability remind us that lots of disposables could be replaced by something durable, like a canvas tote for groceries.

Reaching zero waste won’t be easy. But with a concerted effort by individuals combined with policies that encourage people to use fewer disposable items and make it easier to route trash away from landfills, we can make big strides.

Joe Baker is the Vice President, Editorial and Advocacy for Care2 and ThePetitionSite. He is responsible for recruitment campaigns for nonprofit partners, membership growth efforts, and all editorial content. Prior to Care2, Joe was the Executive Director of N-TEN. Joe serves on the Board of Directors of Death Penalty Focus, the Advisory Board of GiveForward.org and volunteers for the Sierra Club and Amnesty International.

Compost image and tote bag image via Shutterstock.

Endangered Animals of the World

Waste water treatment strategy needed for Cyanobacteria Bloom in Lake Atitlan, Guatemala

By: Guest Contributor, Sherm Davis


Panajachel, Guatemala – On 3 August 2015, a cyanobacteria bloom invaded Lake Atitlan in Guatemala, the first such occurrence since 2009. An infestation of microalgae is considered a bloom when the concentration reaches 2 million parts per liter, and the tests run by the organizations mentioned below prove beyond a doubt that this is a bloom unprecedented in modern history. The question at hand is: What can we do about it?

A series of water samples taken by the Watershed Authority (AMSCLAE) in association with The University del Valle de Guatemala (Altiplano Campus) revealed that there are five major types of phytoplankton in the water, and that three of these (Dolichospermum,Limnoraphis, Microcystis) are classified as cyanobacteria.

The eutrophication (excessive richness of nutrients) of the lake is the main cause of this bloom, and if left unchecked, cyanobacteria (in this case Microcystis specifically) will cause the toxification of the lake and make it unsuitable for human use. This has already happened at neighboring Lake Amatitlán, and to lose a national treasure due to ignorance or political incompetence is unconscionable. These nutrients, of course, come in the form of waste water entering the lake untreated, as well as the inappropriate use of industrial fertilizers which then enter the water supply. Therefore, waste management and water treatment are two of the most important issues  facing the 15 municipalities in the Lake Atitlán basin.

But in an underdeveloped country like Guatemala, where according to Ana Lena Katt, Director of Social Communications at AMSCLAE, there are only waste water treatment plants at 11 of the 15 pueblos in the Atitlán basin, there are both practical and political hurdles to full implementation of a comprehensive water treatment plan for Lake Atitlán.

According to Ivan Azurdia, scientist and Executive Director of AMSCLAE, the funds have existed for seven years to upgrade the entire waste water treatment system and water supply in the Atitlán basin. “Working through the United Nations and the IDB (Inter-American Development Bank), Spain has given Guatemala a donation of US $50 million, matched with another US $50 million in the form of an IDB loan.” Within the $50 million that was given as a donation, a portion was allocated for technical assistance. “The terms of reference exist to develop the master plan,” says Azurdia. “It is ready for implementation.”

There are three organizations that must work in harmony in order for this plan to work. “The IDB signs the checks, INFOM (Instituto de Fomento Municipal, a governmental body on the national level) will provide field supervision during construction of the project, and UNOPS (United Nations Office for Project Services) then manages the project, including procurement of subcontractors, bidding, and proposals. “UNOPS was brought on board to minimize corruption,” says Azurdia. “But time is running out.  For seven years and two administrations, the process had been held back by bureaucratic red tape.”

But finally, on 18 August 2015, bowing to public pressure, INFOM signed the document that will free the funds for implementation of the master plan. Now the race against time has begun. “After all these years of waiting, we have only four months to allocate the funding,” says Azurdia. “After 31 December 2015, the seven-year window for allocation of the funding will close. So although there’s still a lot of work to be done, the funds have finally been released, and we can finally do our job.”

So the first hurdle has been surmounted – the proper official finally released the funding to clean up the lake after the extended bureaucratic idling of two administrations. Now, only four months remain to allocate the funding and begin executing the master plan. Azurdia and his colleagues have been waiting for this day for seven long years. Now, the real work begins to implement a long-term strategy to save Lake Atitlán, one of the world´s natural treasures.


Sherm Davis is a writer, musician, and international educator currently living by Lake Atitlan in Guatemala. His self-help novel, entitled Learning to Stutter, is now available online.

Image credit: Sherm Davis

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