Recreational health advisory re-issued for Detroit Lake, June 14 High toxin levels found in Linn-Marion county lake – The Oregon Health Authority re-issued a recreational health advisory Wednesday, June 13, for Detroit Lake, located 46 miles southeast of Salem. The lake spans both Linn and Marion counties. Water monitoring has again confirmed the presence of harmful algae above Oregon Health Authority recreational guideline values for cyanotoxins. At measured levels cyanotoxins can be harmful to humans and animals. Oregon health officials advise recreational visitors to always be alert to signs of harmful algae and avoid areas with visible scum that looks foamy, thick like paint, pea-green, blue-green or brownish-red, or where small bright-green clumps are floating in the water. On Friday, June 8, OHA lifted a recreational advisory that had been issued May 23 for the lake.