Walter Yu, P.E., LEED AP

Drinking water that's not suited to drink!

The Toxic Waters article series by the New York Times focuses on the worsening impact of pollutant on the nation’s drinking water.

Its most recent article focuses on outdated laws from the Safe Drinking Water Act that regulates 91 of the 60,000 chemicals documented by the EPA as potential pollutants in drinking water.

Many pollutants are carcinogens even in small quantities (in the parts per million magnitude) due to more potent compounds being created by evolving industry processes.

Some chemicals have been found to be harmful to health at smaller quantities than previously thought while others have not been added or updated onthe list of regulated pollutants.

The main issue is that tighter regulations have met resistance from industry lobbying while many continue to consume water from local water districts that may contain polluted water sources.

Complicating the issue is that many health effects such as cancer or birth defects do not appear for years due to the small dosages involved. Testingg drinking water for pollutants from outdated regulations still allows harmful dosages to pass into drinking water.

This holds true in other cases such as air pollution or lead in drinking water: consumption of small doses takes years for effects to appear. Proving the adverse health effects from consuming polluted drinking water is difficult to do, which has made tighter regulations more difficult to pass.

Testing itself is a challenge given that there are approximately 57,400 water systems delivering varying qualities of water. Many water districts still follow the outdated regulations, which may contain either lawful yet harmful chemicals or dosages that are now found to be harmful.

From an environmental engineering perspective, drinking quality has meant developing new technologies to better filtrate water for pollutants and helping water districts implement them. From a sustainability perspective, poor drinking quality not only affects health but reflects the worsening state of our waterways, which have experienced increased pollution.

On an individual level, we can use activated carbon filters (or similar devices) to protect ourselves against possible pollutants as recommended in the book Green, Greener, Greenest by Lori Bongiorno. As with many “green” issues involving health and the environment, we can often chart our own course to affect our own lives.

The Haze in LA.

Growing up in Southern California, I was accustomed to seeing downtown LA covered in a layer of smog (picture, left).

So I was pleased to hear that the EPA has announced stricter national smog standards after years of lax regulation during the Bush administration.

The NYTimes.com website covers the news in this article.

Basically, there are two parts to the new standards:

Primary, health-based protection for people of 60-70 parts per billion in an 8-hour period (the Bush administration tightened the standard from 84 to 75 ppb per 8-hour period).

Secondary protection for wildlife and habitats of 7-15 parts per million-hours (equal to 12-hour periods daily, over 3 months).

Smog is a separate category of air pollutant that affects human health. Sunlight causes chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC’s) to produce ozone, which is the primary component of smog and leads to respiratory problems in humans.

Despite health effects, ozone plays a critical role in sustaining the Earth’s temperature as a part of the atmosphere (approx. 10-30 miles above the Earth’s surface). It reflects UV rays that are harmful to humans and wildlife.

I remember hearing about ozone depletion caused by CFC’s, which were chemicals used in refrigeration. However, public awareness on the issue and the passing of the Montreal Protocol eventually reduced CFC use.

Ozone, ozone depletion and green house gas emissions (which contribute to global warming) have different effects but all involve air pollution caused by human activity. In my opinion, the easiest (and least costly) solution may be to conserve resources rather than spending to look for technology to help us sustain a heavy energy-consuming lifestyle.

The possible solutions to these problems are complex and controversial. They’re the topic of debate because of their immediate impacts on our lifestyle such as higher cost passed to the consumer from increased regulation, which may be the way many states opt to meet these new smog standards.

In conclusion, stricter smog standards are one step in the right direction to lowering air pollution; however, they may not address a deeper problem we have involving the environment: changing human behavior and lifestyle.

Curbside Pick-up for Compost Containers (Green)

I heard this public radio (NPR) news story on food composting in San Francisco a while and wanted to do a short write-up on it.

Composting is now mandatory in the city of San Francisco for residents, businesses and restaurants. Of particular interest are the recycling requirements for construction and demolition (requirements are listed towards the bottom of the page). Basically, all food scraps and construction materials must be disposed of properly and not be thrown away to take up space in landfills.

The city is work hard towards its goal of 75% waste diversion rate, which means 75% or more waste being recycled rather than being delivered to landfills. I previously mentioned the waste diversion rate in my write-up on StopWaste.org.

According to the news story, the city is not the first to implement mandatory composting – Seattle was the first city to do so; however, it did not require all residential units, businesses and restaurants to participate so in that San Francisco is the first.

On the surface recycling and composting may not seem related to civil engineering, but it does have relevance when considered as a part of waste management. More trash means more space required to store it – yes, that’s where the civil and environmental engineers come in to design and build more landfills.

Waste management is surprisingly political and technical in nature – cities and counties must develop policies to manage their trash, and the decomposition process involves various chemical reactions that generate greenhouse gases such as methane.

In conclusion, issues such as waste management, energy efficiency (and generation – think power plants) and water supply (delivery and storage) are technical issues that have immediate impact on our quality of living if not managed and designed for properly.