Provincial monitoring of nitrates in 10 P.E.I. rivers shows levels are rising, according to a recently released report. In three of the streams — the Wilmot, Dunk and Clyde — nitrate levels were over the Canadian Water Quality Guideline for Aquatic Life. The source of the nitrates is mostly agricultural fertilizer, the provincial report says. Environment Minister Steven Myers said recent droughts are the expected culprit. Without timely rain plants can't absorb the fertilizer, and then it washes into streams.