Bull Run Waiver.org is a political group opposed to covering drinking water reservoirs in Portland, Oregon. They making a number of claims that closed reservoirs introduce greater health risks than the existing open-air reservoirs.
Particularly, they are concerned about:
- higher levels of radon and chloroform being trapped in the water/pipes.
- higher levels of anaerobic bacteria due to lower dissolved oxygen levels.
- higher levels of NDMA as it won't be broken down by sunlight.
- higher levels of nitrite and nitrate, from bacteria as it won't be broken down by sunlight.
- higher levels of microbial growth as they won't be disinfected by sunlight.
For example, on their website in the section 'Public health benefits summary of open reservoirs' they say:
Covering or burying the reservoirs will eliminate the natural Radon and trihalomethane gas removal process we currently enjoy in our open reservoir drinking water system. Open reservoirs provide a natural healthy barrier to unwanted gases and chemicals entering the drinking water distribution system. Covering or burying the reservoirs will give Radon along with other toxic and carcinogenic chemicals only one place to vent; our homes, schools, and work places.
Are these claims of the health risks of covered reservoirs true?