San Francisco's green policies put them at the top of the list of cities engaged in environmental innovation. The city is investing millions to improve stormwater management and wastewater infrastructure. It's created the first large scale urban collection of food scraps for composting in the country. So why is the Public Utilities Commission planning to dump bleach into the city's sewer system this summer?
When the weather gets warmer in this temperate city, it causes what's commonly referred to as "rotten egg" smell. The bleach is meant to combat the stink. But we're not talking a few capfuls but 27 milion pounds of bleach in an effort that would cost the cash-starved city $14 million. Why such drastic (and expensive) measures?
As Adam Lowry, chemical engineer and co-founder of Method cleaning products (which are naturally derived and biodegradable), and Michael Braungart, chemist and co-author of Cradle to Cradle: Remaking the Way We Make Things, point out in an OpEd in today's San Francisco Chronicle:
"Other solutions to smelly sewers exist that are far more cost effective in the long term because they avoid the expense of cleaning up the dangerous and persistent chemicals produced by the use of chlorine bleach."
Further, Lowry and Braungart argure, claims that bleach degrades into harmless compounds are misleading, and accordingly they offer viable, less toxic alternatives like hydrogen peroxide (you've probably got it in your medicine cabinet), which produces none of the downstream issues of chlorine bleach and is they explain, already" being used cost effectively today to treat sewage odor in many places in the United States, such as Boston and Miami, as well as internationally in Germany and France."
An even better choice, they argue, "would to use a pro-biotic solution, that is, enzymes or bacteria that would simply "eat" the smell then degrade harmlessly. Used correctly, they could even be used to prevent the problem from occurring again by restoring the healthy balance of microbes in our sewer system."
If scientists are discovering ways to use something as natural as mushrooms to decontaminate brownfield sites, shouldn't San Francisco pursue similarly greener options? If you'd like help the city's Public Utilities Commission to consider alternative solutions to this problem, you can sign the Don't Bleach Our Bay petition on Facebook or here.