Green scum on sky-blue waters

Crow RiverHave you ever seen a bear cry? If the Hamm’s bear could see what’s happening to the sky blue waters he used to sing about, he’d be crying today. From green scum and fish kills in Albert Lea to mining pollution in northern Minnesota and the early closure of the walleye season on Mille Lacs, our water ain’t what it used to be.

hamms_bears_on_log_art_newSure, I’ve seen algae blooms in August for years, but now they are starting earlier, and they’re nastier. In Albert Lea, the Star Tribune reports:

“The sparkling water that made Fountain Lake a source of local pride for decades is long gone, replaced by odorous algae, murky sediment and embarrassing fish kills on beaches in the heart of town….

“Southern Minnesota’s abysmal water pollution won’t go away, state officials say, unless farmers reduce the heavy use of phosphorus, nitrogen and other chemicals that seep off their fields into local rivers and lakes.”

Ron Way and Steve Berg described the algae problem in From runoff to ruin: The undoing of Minnesota’s lakes:

“Here’s what happens: Runoff from farm fields and pavement creates a nutrient overload in nearby lakes. The process accelerates when natural buffers are replaced by lawns and riprap barriers at the water’s edge. When air temperatures rise in the spring, the upper layer of lake water heats up, causing algae blooms that decay and consume oxygen that otherwise sustains fish and their habitat. Climate change compounds the problem by keeping the water warmer for longer periods.

“By mid -to late summer, mats of green scum can dominate the upper layers, forcing rotting algae to seep into deeper, colder parts of the lake, depleting oxygen for the feeder fish like the fatty cisco needed to grow large sport fish. The lake “crashes” when sport fish can no longer thrive. Invasive species — like zebra mussels and Eurasian water milfoil — further complicate the situation.”

They quote U of M fisheries expert Peter Sorensen, who describes Minnesota’s lakes as suffering “death by a thousand cuts.”

The walleye losses in Lake Mille Lacs are one more symptom of our water problems, noted even as far afield as the New York Times. In Mille Lacs, too, the situation is complicated. Aquatic ecologist Dick Osgood explained in the PiPress that “long-term and unmanageable system changes have occurred, such as increased water temperatures, increased water clarity and increasing populations of zebra mussel and spiny waterflea, and perhaps predation by cormorants” in what he characterizes as an “unstable and changing” situation for the lake.

In Northern Minnesota, mining is both a crucial part of the economy and a threat to waters. The state is completing environmental review of PolyMet’s copper/nickel mining application, opposed by most environmental organizations. Current mining lacks adequate oversight, according to Water Legacy, which filed a petition with the Environmental Protection Agency this summer, charging that the Minnesota Pollution Control Agency fails dismally in its oversight duties. Water Legacy’s website says the EPA should “remove the Minnesota’s authority to regulate mining pollution due to undue influence of the mining industry on Minnesota regulators and politicians.”

A few signs of hope come from untiring efforts to protect and restore our waters. Earlier this month, the Minnesota Court of Appeals upheld stricter discharge rules for wastewater treatment plants, despite the legislature’s attempt to delay and defang water protection rules. And MPR recently reported on initial success in a native mussel restoration project in the Twin Cities stretch of the Mississippi River. The water buffer zone rules pushed by Governor Mark Dayton are in place, after a long battle with the legislature.

These signs of hope are too few and far between. Restoring our sky blue waters will take a lot more work and legislative support for clean water, not the kind of stupidity and stonewalling that marked the last session.

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Filed under agriculture, environment

One response to “Green scum on sky-blue waters

  1. Pingback: Saving the Mississippi — and your drinking water | News Day

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