The Oregon DEQ has just released an extensive LCA on the various options of drinking water delivery systems.

DEQ has completed a study that compares a wide range of environmental impacts (including greenhouse gas emissions) of drinking water from the tap, 5-gallon reusables, and single-use bottles. It compares the environmental impacts of tap water (“reduce”) against the impacts of bottled water (“recycle” and “dispose”). The study confirms that while recycling bottles is environmentally preferable to disposing of them, buying bottled water and recycling the bottles is not the best environmental choice. Drinking water from the tap (waste prevention) typically has substantially lower impacts in most categories of environmental impact.

Other highlights of the study include the following:

  • For water that is bottled and consumed within Oregon, the large majority of environmental impacts are typically from producing the plastic resin used to make the bottle.
  • If the bottle comes from across the country or the world, most impacts increase by a factor of 3 or more.
  • End-of-life (disposal) related impacts are very small, with the possible exception of biodegradable plastic bottles. If they decompose in a landfill, the resulting methane is a potent greenhouse gas. Even when landfills capture some of the gas to produce energy, the remaining gas escapes and contributes to climate change.
  • If you choose to drink bottled water, recycling the bottle can have moderate environmental benefits. These benefits, however, are still overshadowed by the negative impacts of making and transporting the bottle in the first place.
  • For tap water, the frequency of washing your container in a dishwasher influences the results more than any other factor.

The study can be accessed on their website here: http://www.deq.state.or.us/lq/sw/wasteprevention/drinkingwater.htm