Geldner honored for work on Louisiana's Coastal Master Plan

Nathan Geldner, IE PhD candidate, won the Best Student Speaker award at the 2021 State of the Coast conference for his contributions to Louisiana’s 2023 Coastal Master Plan.


The Coalition to Restore Coastal Louisiana (CRCL) hosted "State of the Coast 2021", the sixth biennial conference, in partnership with Louisiana’s Coastal Protection and Restoration Authority, The Water Institute of the Gulf and Louisiana Sea Grant. The three-day virtual event was packed with presentations by cutting edge experts and included a mix of scientists, landowners/managers, federal and state agency personnel, local officials, industry and business leaders, resource users, and interested citizens.

At the conference, Gelder shared his work on the social-economic groups most effected by the loss of land mass to flooding. Geldner's advisor, Professor David Johnson has been working on Louisiana's Comprehensive Master Plan since 2009, long before joining Purdue. His team has continued to work on updates to the Master Plan along with other researchers across several institutions.

When asked what one thing could help protect those in greatest threat, Nathan replied, "Fund[ing] an unlimited amount of research on the subject. There's a lot of good work being done, but it's like the Coastline Paradox - the closer you look the more detailed the system is--and at the end of the day we've got a finite amount of time and resources to characterize an infinitely complex system. There always are and always will be more questions that deserve to be asked and answered lying just outside the scope of any major project."

After graduation, Geldner is considering seeking opportunities in the nonprofit, think tank, or non-governmental organization (NGO) space to continue project-based work surrounding environmental hazards. 

"Even though advancing the consideration of social vulnerability when addressing environmental hazards is a research aim of mine, [this work] was largely technical in nature, e.g. how to aggregate a pre-specified measure of social vulnerability spatially and over time..." 

Nathan continued, "However, I believe that applied researchers in most technical fields have a moral duty to consider the impact of their work on socially vulnerable populations, and that failure to do so perpetuates historical injustices and leaves people behind more generally. The folks working to consider social vulnerability for the 2023 revision of the Master Plan are doing a great job given the current state of the science."

CRCL Executive Director Kimberly Reyher stated the importance of the event, “Our state is experiencing some of the fastest rates of land loss in the world, with no end in sight. Sea levels are rising, and about 2,000 square miles of our state has simply vanished in less than a century. It is truly time for action. We are fortunate to have science-based solutions, funding and broad, bipartisan support.”

The Coalition to Restore Coastal Louisiana is a nonprofit organization whose mission is to drive bold, science-based action to rebuild coastal Louisiana through outreach, restoration and advocacy. The Water Institute of the Gulf is an institution that connects academic, public and private researchers and conducts applied research to serve communities and industry. The Coastal Protection and Restoration Authority is a state agency that directs Louisiana’s coastal priorities and implements restoration projects large and small. Louisiana Sea Grant is a college program based at LSU that promotes stewardship of the state’s coastal resources through a combination of research, education and outreach.

Writer: Julia M. Sibley

Sources: Nathan Geldner & David Johnson



Nathan Geldner, Purdue University


In the 2012 and 2017 Coastal Master Plans, storm surge-based flood risk reduction projects were evaluated and selected primarily on the basis of cost effectiveness, represented by the reduction in expected annual damage (EAD) per dollar of cost of a project. Cost effectiveness was explored over a range of uncertain environmental and planning conditions, such as sea level rise, subsidence, economic growth rate, and project costs. The planning process did not explicitly include analysis of how different populations might be impacted by planned projects based upon socio-demographic and economic differences.

However, there is a large and growing literature studying the relationships between socioeconomic factors, race and ethnicity, and social vulnerability to environmental hazards that suggests low-income or underrepresented communities have historically faced a disproportionate share of risk. For the 2023 Coastal Master Plan effort, additional data-driven metrics of social vulnerability are being considered for assessing and communicating outputs of risk assessment analyses (e.g., identifying economic risk to socially vulnerable subpopulations, determining the number of people or households living within the 100-year floodplain, etc.). In this talk, we will describe recommendations for metrics addressing social vulnerability with regard to geographic and economic variations across coastal Louisiana.