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By Brad Wenz
<br />Stearns County SWCD
<br />Getchell Creek, near Albany, was
<br />being monitored closely in the
<br />foggy, rainy evening of July'4,
<br />1995. Most people were indoors
<br />that night, yet the worker was out in
<br />the pouring rain recording stream
<br />readings, oblivious to the inclement
<br />weather.
<br />The water level had beernsteadily
<br />,rising all week. By the 5th, the
<br />_ stream was over its banks in places,
<br />trying to carry the runoff from
<br />44,000 acres of saturated soils.
<br />Ditched and straightened years ago,
<br />_ the creek was performing its
<br />function: empty the watershed into
<br />th'e Sauk River as soon as possible.
<br />The vigilant stream reader `-`lives" in
<br />a green box in the tall grass next to_
<br />the creek. It's a computerized
<br />automatic flow recorder operated by
<br />the Sauk River Watershed District.
<br />_ . At 4:30 pm, July 5, the computer
<br />- sensed the peak flow surge from the
<br />. storm, and samples of the murky .
<br />. water began pumping into recep-
<br />. tacles within the unit, to be tested _ .
<br />- by the Sauk River WD and the .
<br />Stearns County SWCD for phos-
<br />phorous; nitrates and pesticides.. .
<br />Why are we interested? Because .
<br />.Getchell Creek flows into the Sauk
<br />River and the Sauk River flows into
<br />the Horseshoe Chain of Lakes, the
<br />hub of a million dollar recreation
<br />industry. Too much phosphorous
<br />causes algae"blooms" and exces-
<br />siveplant growth, leading to oxygen
<br />-1"he Conservation Mentor
<br />published by the ,
<br />Minnesota Board of Water and Soil Resources
<br />Ron Harnack, Executive Director
<br />612-296-3767
<br />Communications Office
<br />612-297-1893
<br />TDD 612297-5353
<br />FAX 297-5615 ~ ~'
<br />depletions in winter and lots of dead
<br />fish. Scientists call it accelerated
<br />eutrophication. Resort owners call it
<br />bad for business.
<br />Phosphorous isn't the only concern.
<br />Pesticides can cause problems too.
<br />Some ofthese chemicals can cause
<br />subtle disruptions
<br />ofthe food chain "rutting the E
<br />~or affect the Water nOt Or
<br />reproductive t
<br />success offish ~POSIOCI and
<br />and other aquatic' inCreaSeS plri
<br />,organisms. As for - t}i~ pt'Ot~Utef
<br />human consump- ~.
<br />tion, the MPCA JOe f~
<br />has wisel
<br />south; for atrazine and cyanazine
<br />(Bladex) in 1994 and 1995.
<br />Although the July 1995 levels
<br />were among the highest found .
<br />during the study, it was neverthe-
<br />lessgood news, because the
<br />overall levels were low: The
<br />atrazine levels were
<br />y
<br />-. .classified the~Sauk River as a
<br />~nondrinking water source. We do,
<br />however, swim and fish in the river,
<br />and it does outlet into the Missis- .
<br />sippi River; a protected source for
<br />municipa'1 drinking water in St.
<br />Cloud. and other cities downstream.
<br />Where is another reason why we
<br />should be interested in nutrient and
<br />pesticide losses from the watershed.
<br />"These materials represent a large '
<br />investment by the farmer," said Joe
<br />Fitzgerald, retired executive director
<br />- of the Stearns County SWCD.. .
<br />"They can't afford to let these
<br />chemicals run off their fields or
<br />leach into the groundwater and
<br />. pollute their wells."
<br />The tests were positive. According
<br />to the Sauk River WD, the total
<br />phosphorous levels were about
<br />double what they would like to see.
<br />They weren't surprised; average
<br />levels in the past have been high
<br />.also, higher than you'd expect from
<br />a watershed with similar land use.
<br />Low levels of two common herbi-
<br />' cides were also detected. The
<br />Stearns County SWCD, working
<br />with grant money from the Agricul-
<br />tural Utilization Research Institute
<br />(AURI), tested Getchell Creek and
<br />Unnarized Creek, a little further
<br />2
<br />about a third of the
<br />akes On state standard for
<br />re~uteS thesetypes ofcreeks. - .
<br />,Jno~, 17u$Because ofth~e lack of _
<br />itS for research-data; there is
<br />' no state standard that
<br />exists for cyanazine,
<br />gerald according"to the
<br />MPCA. cyanazine is
<br />"slated to be removed
<br />from the market. by the year 2000. ,
<br />"We still can't ignore these
<br />figures," Fitzgerald said. "It
<br />means we have to work harder to
<br />- keep these chemicals on the fields _
<br />where they're supposed to be."~
<br />One answer is runoff control, .
<br />according to Minnesota Depart-
<br />ment ofAgriculture surface water
<br />hydrologist Paul Wotzka. "You =
<br />have to get back to'basic conser- '
<br />` vation practices that slow down '~
<br />runoff if you're going to control
<br />pesticide pollution in surface
<br />water," he said. Wotzka has .
<br />monitored pesticide levels-in
<br />Minnesota waters for several
<br />years. He said that crop residue,
<br />management, contour farming,
<br />terraces, grassed waterways, and
<br />filter strips can reduce herbicide
<br />runoff over 80 percent, depending
<br />on field conditions.
<br />"We've always promoted these '
<br />types of practices with farmers," =
<br />said Fitzgerald.. "Putting the -
<br />brakes on water not only reduces .,
<br />erosion and runoff, but increases
<br />profits for the producer-Only one
<br />extra inch ofwater helped into the ,
<br />soircari mean...more corn for the
<br />farmer, and a lot less herbicide •
<br />and fertilizer loss."
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