08/27/2015 07:00 EDT | Updated 08/27/2016 01:12 EDT

Grassy Narrows First Nation declares emergency over bad water

Grassy Narrows First Nation in northern Ontario is declaring a state of emergency on Thursday because no safe drinking water is available in the community.

The First Nation, also known as Asubpeechoseewagong, has been under a boil water advisory for more than a year, but new concerns are emerging about the extent and longevity of the problems.

CBC News was granted advanced access on Wednesday to documents obtained by the First Nation showing turbidity at the 120 times the Ontario guidelines and the presence of potentially cancer-causing disinfectant by-products (DBPs) that may not be removed by boiling.

"The community is delivering bottled water door-to-door to ensure that their families, many which have already been impacted by mercury poisoning, have safe drinking water," according to a statement from Grassy Narrows.

Many residents of Grassy Narrows suffer the health effects of mercury that was dumped in the local waterways 50 years ago.

A 2001 risk assessment of the water system at Grassy Narrows by the Bimose Tribal Council showed the presence of the same problems with turbidity and DBPs noted in a 2015 letter to the chief from the Ontario Ministry of the Environment and Climate Change.

"It is likely that these drinking water conditions persisted for at least 15 years before provincial MOE testing highlighted them and advisories were put in place," the statement from the First Nation said.

Problems with the water treatment plant were identified in the 2001 risk assessment, but the community says it doesn't have the funds to carry out the necessary improvements.