Sunday, March 22, 2020

March-April Water Column

The month of March brings both change and hope. Trumpeter swans have returned to our waters and bird enthusiasts are watching the migratory “radar” for the ebb and flow of migrations heading for parts north. All seems to be going according to plan with rivers opening up flowing ice-free as they head north to Lake Superior. Historically, spring runoff has been a time when rivers are most actively evolving. Major runoff events and peak flows change the course of waterways over time in natural processes where erosion and sedimentation balance each other out in a healthy watershed.
Unstable banks like this one at Copper Falls State Park 
are found along many area streams. 
                                                         Photo by Diane Daulton

Land use changes since pre-settlement times in the Lake Superior basin have greatly influenced our geologically young landscape, especially in recent years with significant rainfall events and subsequent flooding. Why, one might wonder? Back in the 1950’s after a series of large floods and washouts, the Red-Clay Interagency Committee was tasked with studying and demonstrating techniques for reducing upland and roadside erosion and stabilizing river bluffs and streambanks. Most people don’t realize that deforestation, subsequent farming, and channelization from road building and culverts forever changed the landscape resulting in a significant nonpoint source pollution problem that we still face today.

In the upper reaches of Lake Superior’s watershed, red clay soils and sands resulting from past glacial Lake Duluth shorelines converge in a steep transition zone of ravines and valleys making for a “perfect storm”. The increased volume and power of runoff results in an imbalance that fuels gullying, disconnects headwaters’ wetlands, degrades streambanks…scouring out channels and perching floodplains, while vast amounts of sand and sediment are transported downstream. Research Hydrologist, Faith Fitzpatrick, with the U.S. Geological Survey (USGS) cautioned that small land use changes can matter. She explains, “Because of the steepness and clay soils (that promote runoff), a small change in the amount of runoff, from changing the vegetation type, decreasing roughness of the land surface, or altering drainage pathways may easily destabilize a ravine and cause gullying and groundwater sapping.” Although recent years’ extreme rain events have exacerbated this problem, it is not new, just evolving…as are efforts to study and better understand the watershed as a recovering fluid system.

Fitzpatrick has been studying fluvial geomorphology in our watershed since the 1990’s, looking at historic erosion and deposition, studying the function of our streams and their interaction with the landscape around them. One has only to paddle the White or Bad Rivers to see >100-foot tall slumping banks along bends in the river where mass bank erosion is obvious. Fitzpatrick noted, “The extreme floods in 2016 and 2018 that hit northern Wisconsin will likely leave a sedimentary signal that will live on in the geologic record. The floods caused major geomorphic change over a period of hours. New valleys were formed and, in some places, more sediment was deposited on floodplains than that which accumulated over the last 150 years since land clearing and Euro-American settlement. 
Flood events exacerbate unstable hydrologic conditions causing damage.
Deep sand deposits are clearly visible on N. Fish Creek 
downstream of US Hwy 2.
                   Photos by F.Fitzpatrick, U.S. Geological Survey

The single failure of the culvert and washout of the road embankment at Hwy 2 across North Fish Creek during the 2018 Father’s Day flood resulted in approximately 800,000 cubic feet or 30,000 tons of sediment---that sediment covered the valley bottomland for at least 1 mile downstream with a 1-foot blanket of sand and muck. That sediment, more than the average years-worth from the entire watershed, will likely be stuck in that reach for thousands of years.” In continued efforts to “slow the flow”, Ashland County and their Land & Water Conservation Department, USGS, U.S. Fish & Wildlife Service, U.S. Forest Service, and the Wisconsin Wetland Association are working on a new Federal Emergency Management Agency (FEMA) grant project in the Marengo River sub-watershed to adapt nature-based flood risk reduction strategies to better fit our landscape.

Mary Jo Gingras, Ashland County Land Conservationist explains, “The FEMA grant will help inform efforts to repair hydrologic conditions by analyzing fluvial erosion hazard features, specifically where flood storage areas have been reduced, or lost, in the upper watershed due to degraded wetlands or compromised floodplains. In the 2016 and 2018 floods, the Marengo River watershed experienced substantial flooding; resource managers have made connections between flood damage to roads, culverts, and bridges and degraded natural conditions that could have helped mitigate storm damage.” Wisconsin Wetlands Association Specialist Kyle Magyera warned that flood resiliency in our area will not take place overnight. He noted, “We will have to let rivers move and repair themselves naturally, but we can help kick-start the process by repairing hydrology and reconnecting streams, floodplains, and wetlands to better control water movement.”
Incised headwater streams can damage protective wetlands,

Small changes in land use can destabilize a ravine causing
gullying and groundwater sapping.

            Photos by Kyle Magyera,
                                 Wisconsin Wetlands Association

Recent history has taught us that nature is not always in concert with the latest engineering standards and that, over the years, humans have made costly mistakes either from lack of insight or differing value systems. In the last decade, the Northland has faced threats to water quality posed by increased rainfall events, such as massive culvert failures and washed out roads, but also potential impacts from large-scale agricultural expansions, and long-term implications of iron mining in the Penokees.


While these issues are dormant for the moment, the effort to re-route Enbridge’s Line 5 pipeline is bringing back the age-old dichotomy of clean environment versus the economy. Opinions are sharply divided amongst people living in the watershed and many landowners have already signed agreements with Enbridge to lease their land in perpetuity or to sell outright. According to Enbridge Energy, a multinational Canadian company, “Line 5 is a vital link to propane and other energy supplies for the upper Midwest. Every day, this 645-mile-long, 30-inch diameter pipeline plays a critical role transporting 540,000 barrels of light crude oil, light synthetic crude oil, and natural gas liquids to a regional network for this area.” Since the Bad River tribe has requested removal of the existing pipeline on the reservation, the company’s plan “B” is to skirt around that approximately 12-mile section by moving further upstream in the watershed. Common sense suggests that this alternative neither benefits the Bad River Tribe or Ashland County, as it enlarges the watershed that would be at risk. Further, the project could put groundwater aquifers at risk, as little is known about the exact path of local groundwater, except that it provides drinking water for many rural residents.  

Aerial imagery shows historic movement of Bad River
channels and resulting oxbow lakes where the river
intersects with existing pipeline corridors.
               Google Photo courtesy of Joe Bates

According to Enbridge’s Public Service Commission of Wisconsin Public Interest Determination
Application (Feb 2020), the proposed 41 mile-long re-route for the pipeline encompasses 182 new river crossings, along with 86.6 acres of wetland impacts, all of which are still located within the Bad River (Lake Superior) watershed. Under stable conditions rivers naturally change course over history cutting themselves off, forming oxbow lakes, and evolving in ways we may not anticipate, so why would we take chances under less than stable watershed conditions? It seems self-evident that we owe it to future generations to carefully consider the risks and economics of any endeavor that requires a commitment in perpetuity.

For landowners interested in learning more about Line 5, facts and disclosures regarding easements, and how to make informed decisions for their property and the watershed.  Midwest Environmental Advocates has partnered with Wisconsin's Green Fire (a nonpartisan group dedicated to management of natural resources) to produce a series of guides that educate the public on the various regulatory processes involved with the proposed reroute of Enbridge's Line 5.  Links can be found at or under the "issues and actions" tab.

Lake Superior is a freshwater inland sea worth protecting.
Photo by NOAA
Water resources are a huge part of a complex web of life that supports our daily lives, and successful and sustainable communities depend upon more than clean water. We need jobs, homes, food, and infrastructure for staying warm, getting around, and living our everyday lives. Arguably for many of us, living in the Lake Superior watershed adds a superior quality of life…with its beautiful vistas, vibrant tributary streams, and fishing and recreational opportunities. There may be no easy answers, but our hope is that we can insure the health of our waters and habitat with a combination of technology, engineering, citizen involvement, and most importantly, a responsible long-term protective philosophy. After all, our rivers and streams, wetlands, and ultimately the Great Lakes are worth protecting as one of the most important sources of fresh water on the planet.

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