Big Chem-EZ: Why is southeastern Louisiana heavily impacted by storms?

Dear Big Chem-EZ,

Since Hurricane Ida, I have been interested in learning if anything can be done to lessen the impacts of large storms in Louisiana. How do the engineering industries in Louisiana impact how people in Louisiana are affected by storms?

Louisiana has many claims to fame, including its food, liveliness, and hurricanes. While the effects of flooding and storm damage in New Orleans hold a significant media presence, the river parishes along the Mississippi River endured more damage during Hurricane Ida. One such community is the Pointe-au-Chien Indian tribe along the Bayou Pointe-au-Chien in South Louisiana. After Hurricane Ida, 150 families from the Pointe-au-Chien community needed to be relocated for temporary housing and rebuilding [1]. The loss of Louisiana’s wetlands through coastal erosion is one reason tropical storms and hurricanes heavily impact river/coastal communities such as the Pointe-au-Chien [1].

One estimation declares that 2.7 miles of wetlands can reduce a storm surge by one foot [2]. With an estimated hourly loss of a football field of wetlands in Louisiana, coastal erosion has a considerable negative impact on the industries and people of Louisiana [3]. There are many contributing factors to Louisiana’s coastal erosion, including the effects of the petrochemical industry. Over the past century, human activities such as the construction of canals and levees that prevent the natural deltaic cycles of the Mississippi River have altered Louisiana’s natural hydrology. When the river cannot travel its natural course, sediment from the river cannot be deposited, resulting in an imbalance in the loss and gain of land [2]. Below is an image demonstrating land loss in Louisiana.

Rapid erosion and land loss seen in Isles Dernieres in Southeast Louisiana (Shirley)

There are many proposed engineering solutions to fight Louisiana’s land loss. Barrier island renourishment for coastal restoration serves as a possible solution. Barrier island renourishment in Louisiana aims to restore beaches, dunes, and back-barrier marshes by dredging material from the Mississippi River to increase island width and height [4]. Sand dunes can be improved by adding sand-trapping fences and vegetation to decrease the impact of erosive forces on barrier islands. Other solutions to erosion include allowing the river to take its natural course by removing levees and canals. However, this solution causes controversy because it directly affects the communities levees protect from flooding [4].

The State of Louisiana has implemented 17 Barrier restoration projects from 2008 to 2016. These projects spanned across Terrebonne Bay, Barataria Bay, and the Chandeleur Islands and have obtained a net gain of about 2,200 acres of land [5]. With the continual fight against coastal erosion in Louisiana, Louisiana’s wetlands can continue to be restored, and residents of Louisiana can have protection from natural disasters and storm surges.

If you feel motivated to advocate for coastal restoration in Louisiana, you can support the following organizations fighting erosion.

• https://stormwatersolutionsla.com/
• https://bayoucreek.net/erosion-control-projects/
• https://coastal.la.gov/
• https://glasshalffullnola.org/home

References:

[1] “The Pointe-Au-Chien Indian Tribe Needs Your Help.” Restore the Mississippi River Delta, 20 Oct. 2021, https://mississippiriverdelta.org/the-pointe-au-chien-indian-tribe-needs-your-help/.

[2] Shirley, Jolene S. “Louisiana Coastal Wetlands: A Resource at Risk.” Louisiana Coastal Wetlands: A Resource At Risk – USGS Fact Sheet, https://pubs.usgs.gov/fs/la-wetlands/.

[3] “Louisiana’s Oil.” Wetlands and Coastal Erosion,  https://www.southeastern.edu/acad_research/depts/biol/programs/wetlab/index.html

[4] “Barrier Island Restoration.” Restore or Retreat, Inc., https://restoreorretreat.org/solutions/barrier-island-restoration/.

[5] Johnson, E. (2021, July 8). “Louisiana embarks on largest project yet to keep its barrier islands from disappearing.” Restore the Mississippi River Delta. Retrieved November 15, 2021, from https://mississippiriverdelta.org/louisiana-embarks-on-largest-project-yet-to-keep-its-barrier-islands-from-disappearing/.