Newsletter

                                                                                                                                                                          April 2013

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Since its formation in 2009, the Lake Pepin Legacy Alliance has been working hard to protect the natural heritage of Lake Pepin.  From time to time, it is important to pause and reflect on what we know, what we still don’t know, what we have accomplished, and where we will go from here. 
As our mission and focus expands, we will need your help in funding this important work.  Please consider a tax deductible donation to the Lake Pepin Legacy Alliance by visiting our donation page or sending your check to:
Lake Pepin Legacy Alliance PO Box 392 Red Wing, MN 55066
At this time we would also like to ask our readership to consider friends or neighbors who may benefit from receiving our newsletter.  Please feel free to encourage others to send us their contact information by emailing Rylee at rylee.main@lakepepinlegacyalliance.com. 

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Where is the sediment coming from? In 2011, Shawn Schottler et al. published a study in the Journal of Environmental Science and Technology which outlined the use of geomorphic change detection techniques to demonstrate that “the dominant source of sediment has shifted from agricultural soil erosion to accelerated erosion of streambanks and bluffs, driven by increased river discharge.”
While disputes over the source of sediment still occur, most now agree that increased river flow is the primary driver of erosion and sedimentation. Still, questions remain: is our changing climate the culprit of increased river flow, or is it artificial tile drainage on agricultural land, or perhaps urban stormwater? Is it possible that we all have a part to play in managing our water resources?
A new study by Schottler et al., published this year in the Journal of Hydrological Processes, sheds light on the changing conditions of our river systems. The article, “Twentieth Century Agricultural Drainage Creates More Erosive Rivers,” attempts to disentangle the effects of climate and land-use by comparing changes in precipitation, crop conversions, and drained depressional areas in 21 watersheds in Minnesota over the past 70 years.
The study found large and significant increases in water yield, ranging from 45-200%, for over half of the watersheds during the months of May – June, accounting for one-third of the total annual increase in water yield. Interestingly, the article states that May-June precipitation has been constant or has decreased since 1940, stating further, “the fact that the largest changes in water yield and runoff ratio occur during May-June, a period with no increase in precipitation (and more than a month after snowmelt), strongly implies that seasonal changes in river hydrology are not the result of increases in precipitation.”
This same study looks more closely at the agricultural conversion to soybeans which has largely displaced small grains and forage crops.  Specifically, the study stated that previously grown grains and forage crops, which actively grow early in the spring, reduce the available soil moisture through evapotranspiration (ET).  Soybeans, on the other hand, which are planted later in the spring, do not consume water through ET until nearly a month later.  The result is that a greater proportion of spring precipitation enters our river systems.
Further, and perhaps most importantly, subsurface drainage has accompanied this crop conversion for the very practical reason that it benefits both corn and soybean yields.  According to the article, “the larger impact of artificial drainage on the hydrologic budget is through reduction in ET losses from depressional areas (loss of residence time) … What is clear is that precipitation that was once lost to ET is now being transported to the rivers.” The authors conclude that “efforts to mitigate excessive sediment loads and turbidity must include strategies to manage watershed hydrology and reverse conditions contributing to higher river flows.”
What don’t we know? Although we still face some scientific uncertainties, such as the long-term effects of climate change, one of our greatest challenges is determining how to integrate new information into a human system that values tradition, efficiency, and economic profitability. Our scientific understanding of the sediment issue necessitates that we implement practices which allow for water storage and shoreland stability, if progress is to be made.  State and federal programs incentivize these restorative practices. Yet, the changes that will aid in cleaning up our rivers require an investment many are unwilling to make.  Payments from conservation programs cannot compete with land prices, and many agricultural producers are resistant to investing in these changes without sufficient financial and technical assistance.
To protect the natural heritage of Lake Pepin, we not only need to address the pollutant sources upstream, but we also need to restore the lake itself.  Projects such as island building and strategic dredging could provide great benefits in this effort.  However, these projects are costly, and would likely require the Army Corps of Engineers to be the driver in engineering them. Historically, the Army Corps of Engineers’ involvement in the South-Metro Mississippi River has been focused on commercial navigation – maintaining an open channel for shipping. This focus has not changed.
What progress has been made? Perhaps our greatest achievement as an organization, thus far, is contained in the relationships that we have developed with people on all sides of the issue.  The Upstream/Downstream Friendship Tour created trust and understanding between residents near Lake Pepin and producers and local government staff upstream.  The Lake Pepin Legacy Alliance maintains a strong working relationship with our friends upstream, while also partnering with other environmentally-focused organizations, agency staff, researchers and academics, and elected officials, where appropriate.
These partnerships have allowed us to provide up-to-date information on our website, develop our Local Resource Management Scorecard, collaborate on events, attend field day demonstrations of conservation best practices, and continue to be a voice for Lake Pepin.
We’ve witnessed changes in perspectives when producers feel respected and the focus is kept on common ground solutions.  We’ve observed the innovation that exists among those working on new conservation drainage practices. We’ve been inspired by the collaborative efforts of so many passionate groups across the state of Minnesota and we’ve been reaffirmed by the willingness of those groups to work with us towards common goals.
Where do we go from here? As we near the completion of our initial set of data for our Local Resource Management Scorecard, we are planning for the next phase of the project: interviewing local government staff in each county within the Minnesota River Basin.  Our goal is to continue our relationship building while providing both credit and accountability to the counties whose water drains into the Minnesota River, and whose soil settles in Lake Pepin.
Additionally, we hope to bring some focus back to Lake Pepin in the coming months.  A new project has been proposed by the Army Corps of Engineers to address navigation concerns in lower Pool 2, just north of Lake Pepin.  The project would provide a safer and more reliable navigation channel, but will also have a sediment increase of 0.5% on total sediment entering Lake Pepin annually.  Although the Army Corps is not required by law to undertake any mitigation projects, it may be the appropriate time to sit down with our local partners and Army Corps staff to drive a solution.
Thank you! The Lake Pepin Legacy Alliance is greatly appreciative of the donations we receive.  It is through these contributions and the continued concern for the lake from our members that we are able to continue our work.  Your support, in whatever form it takes, is invaulable.

The Lake Pepin Legacy Alliance is now on Twitter! Follow us @LakePepinLA  

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