Woods and Waters An outdoor blog by John McCoy

In this Sept. 16, 2016, photo, dead northern pike are seen in the Des Lacs River near Burlington, N.D.  State health and wildlife officials are investigating a fish kill in the river in northern North Dakota. (Kim Fundingsland/Minot Daily News via AP)Fish kills happen. Everyone knows that.

Pipeline ruptures, tanker-truck wrecks, train wrecks and accidental discharges from industrial sites are unfortunate, but until someone creates a perfect world such incidents are going to occur from time to time.

It still hurts to see the results — fish dead, recreation harmed, ecosystem damaged.

It hurts twice as bad when the fish kills are caused by people who, ironically, are seeking to prevent pollution. The latest example is a fish kill in a Colorado water-supply reservoir. From the Associated Press:

JOHNSTOWN, Colo. (AP) — Colorado Parks and Wildlife is investigating Johnstown officials after their attempt to treat an algae outbreak left nearly 1,000 fish dead.
The Greeley Tribune reports that Parks and Wildlife spokeswoman Jennifer Churchill says a worker put a copper sulfate into the town’s reservoir this summer to treat the algae. She says chemical ended up suffocating 972 fish.
The National Pesticide Information Center says copper sulfate can cause sudden plant death, causing fish to suffocate because of depleted oxygen and clogged gills.
The reservoir is used for the town’s drinking water and recreational fishing. Officials didn’t say there was any concern about the chemical’s effects on human health. In higher concentrations, it can cause nausea.
Churchill says officials aren’t currently considering criminal charges or fines.

Sigh. The Churchill spill immediately brings to mind a 2010 incident on West Virginia’s Blue Creek. That spill, caused by workers seeking to drain a tailings impoundment, killed smallmouth bass, rock bass and trout along 9 miles of the stream.