Environmental Impacts

Enbridge line 5 extends from Superior, WI to Sarnia, Ontario, Canada going under the Great Lakes at the Straits of Mackinac where is splits into two pipelines[1]. In 1953, the 635-mile pipeline was constructed[2]. 23 million gallons of oil flow through the pipeline daily underneath where Lake Michigan and Lake Huron converge[3]. Enbridge claims, “. . .the Line 5 Straits of Mackinac crossing remains in excellent condition, and has never experienced a leak in more than 60 years of operation[4].” However, multiple sources reveal that the pipeline has leaked multiple times in the past. According to sources, Line 5 has approximately 29 oil spills from 1968 to 2015 which in total has spilled more than 1 million gallons of oil and gas products[5]. Furthermore, this aging pipeline is exhibiting signs of wear and tear where the metal casing has fallen off underwater[6]. Enbridge line 5 is a disaster waiting to happen, which has implications for the health of the Great Lakes ecosystems and services.

The Great Lakes are the world’s largest surface freshwater system (not including ice caps) which holds 84% of North America’s freshwater and 21% of the world’s freshwater supply[7]. One study of the Great Lakes basin calculated a gross regional product (GRP) of $4.1 trillion USD for the Great Lakes region economy[8]. However, it is difficult to quantify the total value of the Great Lakes, because they provide countless ecosystem and cultural services to many people. Ecosystem services as defined by Steinman et al. are “type, quantity, and interactions of natural features required to generate observable and measurable ecological outputs.[9]” The Great Lakes provides a wide range of ecosystem services: flood protection, fish spawning grounds and nurseries, clean drinking water, pollution control, and fisheries. In addition, coastal wetlands of the Great Lakes provide nutrient retention, which prevents high amount of phosphorus and nitrogen from leaching into the water system by storing nutrients through sedimentation and burial of particulate forms[10]. This is particularly important in maintaining the biodiversity in the Great Lakes ecosystems, because high concentrations of nitrogen cause algal blooms that take up all the nutrients and oxygen, killing fish. It is unclear if Enbridge considered these services the Great Lakes provide when Enbridge proposed and constructed line 5 through part of the Great Lakes, compromising its integrity and ecological/cultural services.

        The Straits of Mackinac have a complex current system which made it difficult to determine how far oil would travel if an oil spill occurred in the area. A researcher from the University of Michigan modeled the currents of the Straits of Mackinac to illustrate the threat of an oil spill in this area[11]. The model predicted that 700 miles of shorelines would be at risk for contamination/exposure to oil if there was a spill[12]. This could potentially affect the nutrient storage services that the coastlines provide, causing an increase of nutrients in the water since wetlands will not be able to store nutrients. Furthermore, 15% of Lake Michigan’s water and 60% of Lake Huron’s water would be affected by visible oil[13]. Piping plovers are an endangered species living on beaches along the shorelines of the Great Lakes, and their habitat is at risk of being contaminated by line 5 [14]. This is one example of many animals that would be affected by an oil spill in the Straits of Mackinac. In addition, the Great Lakes are sacred to the Indigenous peoples living near them. Beaver Island is a part of indigenous creation stories, and it is near the Straits of Mackinac thus making it vulnerable for possible contamination. The Great Lakes is fundamental for the well-being of the animals and people in the region and globally. We are dependent on the Great Lakes as a source of water and life, and we must ensure its beauty and fresh waters will not be contaminated for the sake of past, present, and future generations.

Author: Sherralyn Sneezer

[1] “About Line 5.” n.d. Accessed February 18, 2018. https://www.enbridge.com/projects-and-infrastructure/public-awareness/line-5-michigan/about-line-5.

[2] Ibid.

[3] “The Problem.” n.d. Accessed February 18, 2018. http://www.oilandwaterdontmix.org/problem.

[4] “About Line 5.” n.d. Accessed February 18, 2018. https://www.enbridge.com/projects-and-infrastructure/public-awareness/line-5-michigan/about-line-5.

[5] “Aging Enbridge Pipeline Has Spilled 1 Million-plus Gallons of Oil in Its Lifetime, Report Finds.” 2017. April 26, 2017. https://insideclimatenews.org/news/25042017/enbridge-pipeline-mackinac-line-5-michigan-oil-spill-risk.

[6] Ibid.

[7] US EPA, REG 05. 2015. “Great Lakes Facts and Figures.” Overviews and Factsheets. September 18, 2015. https://www.epa.gov/greatlakes/great-lakes-facts-and-figures.

[8] Steinman, Alan D., Bradley J. Cardinale, Wayne R. Munns, Mary E. Ogdahl, J. David Allan, Ted Angadi, Sarah Bartlett, et al. 2017. “Ecosystem Services in the Great Lakes.” Journal of Great Lakes Research 43 (3): 161–68. https://doi.org/10.1016/j.jglr.2017.02.004.

[9] Ibid.

[10] Sierszen, Michael E., John A. Morrice, Anett S. Trebitz, and Joel C. Hoffman. 2012. “A Review of Selected Ecosystem Services Provided by Coastal Wetlands of the Laurentian Great Lakes.” Aquatic Ecosystem Health & Management 15 (1): 92–106. https://doi.org/10.1080/14634988.2011.624970.

[11] “Worst Case Oil Spill Straits of Mackinac.” 2016. March 26, 2016. http://graham.umich.edu/water/project/mackinac-oil-spill.

[12] Ibid.

[13] Ibid.

[14] “USFWS: Endangered Species in the Upper Midwest.” n.d. Accessed February 21, 2018. https://www.fws.gov/midwest/endangered/lists/e_th_pr.html.