Nitrate levels are high in P.E.I.'s drinking water and will get worse if farming practices don't change, a joint federal and provincial study shows.

'The amount of money for providing water would be doubled.'— Researcher Martine Savard

The Wilmot River watershed, just east of Summerside, was found to be one of the most contaminated areas of the Island, with one in five wells tested during the study showing levels of nitrates above Health Canada guidelines. Martine Savard of the Geological Survey of Canada told CBC News there are eight more watersheds on P.E.I. where the situation is similar.

Savard said the study shows nitrates are coming from chemical fertilizers spread on fields. And if things don't change, the situation's going to get worse.

"The number of watersheds that are belonging right now to the highly impacted group would increase significantly, perhaps by 25 per cent," she said.

Twenty federal and provincial researchers were involved in the study, taking water samples from wells around the Island over the course of several years. Nitrates interfere with the body's ability to absorb iron, and are particularly a problem for infants, who can develop blue baby syndrome, in which the blood's ability to carry oxygen is reduced.

Savard said the study also shows that if farmers in the Wilmot watershed stopped using fertilizers today, it could take 20 years for nitrates to come down to a normal level. The cost of treating contaminated water or digging new wells could be expensive for homeowners and municipalities.

"If there was no alternative source of water, then we could think the amount of money for providing water would be doubled," she said.

The study doesn't make specific recommendations about how to reduce the amount of nitrates in P.E.I.'s groundwater, but it says the province needs to take action soon.