Current Conditions, November 7, 2019

Welcome Back to the NTC’s Voice of the Driftless 

By Jeffrey S. Broberg

Trout fishing in SE Minnesota is now closed to angling except in the five cities and three State Parks that have continuous seasons. But Iowa is open for trout all year.

Well, things changed in a hurry Tuesday night with 3-7” of snow along the I-90 corridor…now cold. With no rain in the last week, the streams have cleared nicely.  I have heard stories of good fishing with small nymphs and orange or pink scuds and reported hatch of tiny brown or tan, size 20 or 22 mayflies in the Root River basin once the sun warms the water.

The Great Migrations along the Missippi River Flyway

Every year in October and November, millions of birds leave their northern nesting grounds and head south, many of them down the Mississippi.  It is definitely worth the visit.  Brownsville has excellent viewing opportunities as do Brice Prairie and Genoa in WI.

If you can’t go, there is an excellent Flyway Cam from Lake Onalaska on Pool 7 brought to us by the Raptor Resource Project

https://explore.org/livecams/raptor-resource-project/mississippi-river-flyway-cam

Early this morning, the Cam was showing a dozen eagles clustered around the edge of the marsh crabbing to eat a dead goose

frozen in the ice. Dozens of eagles were roosted nearby, and flocks of ducks, geese, and swans flew overhead.

Other great resources show off the beauty of our region.  I like the Facebook Page Wayne Bartz Photos.  Our friend Wayne has been mentioned here before with his SE Mn Hatch Chart.  This week Wayne was out taking pics of the swans:

Wayne Bartz Photos:

https://www.facebook.com/search/top/?q=wayne%20bartz%20photos&epa=SEARCH_BOX

Cool Tools

Lots of cool tools drew my attention this week on the web.  I was looking at the hydrology of Garvin Brook, and I found two MNDNR sites useful.

1. The MNDNR NWI Wetland Finder is a tremendous interactive mapping tool for the whole state. This mapping tool is a site I will use again and again. The updated version of the National WetlandInventory (NWI) shows various map layers with the location and wetland types that were identifed from LiDAR and high-quality air photos. The legend on the bottom of the screen lets you choose street map view, color air photos and LIDAR Hillshade views that reveal the bedrock landscape and the wetland seeps that feed the stream.
2. The second site of interest was also related to Garvin Brook and the groundwater studies that have been done in recent years. MNDNR now has an online “Minnesota Groundwater Tracing Database” where the public can download all of the Minnesota groundwater tracing reports.
   Winona County has 19 different dye trace studies; Fillmore has 90! There is a wealth of fascinating data here for hundreds of spring sheds.

https://arcgis.dnr.state.mn.us/ewr/wetlandfinder/

The second site of interest was also related to Garvin Brook and the groundwater studies that have been done in recent years. MNDNR now has an online “Minnesota Groundwater Tracing Database” where the public can download all of the Minnesota groundwater tracing reports.  Winona County has 19 different dye trace studies; Fillmore has 90! There is a wealth of fascinating data here for hundreds of spring sheds

 

The dye trace studies have proven to be a smart and effective way to figure out how water flows through our fractured karst aquifers.  A fluorescent dye that is detectable in parts per million concentrations is injected into sinkholes and stream sinks. Small packets of activated charcoal are set downstream in the stream, springs, and the water from nearby wells.  The charcoal absorbs the dye and can be extracted in the lab, and the hydrologists can tell how long it takes for the dye to travel underground from the injection site to the spring or the well.

https://www.dnr.state.mn.us/waters/programs/gw_section/springs/dtr-list.html

In Garvin Brook, the dye was shown to travel underground between 150 and 655 feet/day. The water is flowing in underground aquifers and can go a mile in a week!  The studies prove that the groundwater that we drink and the surface water that supports our trout are the same things.

Garvin Brook Fish Kill, September 30, 2019

Three weeks ago today, a significant fish kill wiped out all the fish in Farmers Park.  The stream reach above the confluence with Peterson Creek up through Farmers Park was affected, and dead trout, sculpin, suckers, and other fish were recovered by the DNR.

The fish kill was reported to the duty officer (1-800-422-0798) by three different parties about four days after a week of rain. There is still no word of the cause, and DNR officials have said they do not believe this is a fish disease or natural event and that they think that humanmade sources are responsible.  DNR, MPCA, Ag Dept. and County officials are reviewing pesticide application and manure spreading in the watershed above Farmers Park.

NTC and the Minnesota Well Owners Organization are aking the fish kill investigators to determine where the tainted water went as they try to figure out what killed so many fish.

In 2014 and 2016, hydrologists conducted dye trace studies in Farmers Park.  The dye placed in the bedrock at the bottom of the drainage way shows that the Garvin Brook surface water recharges the shallow groundwater and can even come out in private wells.

Stay tuned for more information about the Garvin Fish Kill