Coastal Master Plan 101: How the Plan was Built

 

The issue of coastal land loss affects everyone who lives in Louisiana.  Our coastal wetlands are the root of our culture, the source of our incomes and the place that generations of families have called home.  And it is disappearing at the rate of one football field every hour.

More than 250 residents turned out for the CPRA public meeting on the Master Plan in Houma

It’s a problem that’s too big to ignore, and we all want to do something about it.

Before the Louisiana Legislature this spring is our best plan yet for taking action against coastal land loss:  the 2012 Coastal Master Plan.  This plan, drafted by the Coastal Protection and Restoration Authority of Louisiana (CPRA) is a strategy that coordinates the next 50 years of coastal restoration projects, in order to most effectively rebuild and protect our coast.  CRCL takes a closer look at the 2012 plan in a four-part series that we call “Coastal Master Plan 101.”

For our first installment, we examine how the plan came about.

Often described as a “living document,” the Coastal Master Plan is updated every five years as required by the state legislature.  The first version of the plan was approved in 2007, and featured a broad-based set of goals that stressed the importance of limiting economic loss, using natural methods to restore wetlands, protecting resources valuable to economic activity and preserving the cultural heritage of the coast.

The 2012 Master Plan builds on the work of the 2007 Master Plan but gets more specific in exactly how to accomplish these goals.  The 2012 plan places the greatest emphasis on projects which can deliver the most rebuilding of land and reduce the most risk associated with storms and flooding.  But it also considers which of these projects have the most adaptability to changing conditions and the least amount of cost.

Decision Criteria:

So what should a coastal master plan accomplish?  Some citizens might want to see our coast provide more seafood or habitat for wildlife.  Still other citizens may think that the coast should protect communities from storms and hurricanes.  Considering that our coast provides a huge number of important functions the state decided to identify two key principles that incorporated what most citizens want from our coast:

  1. Building land
  2. Reducing risk

Although these two criteria don’t specifically describe everything we want from our coast, they do capture most of what is important to citizens.  We all know that our wetlands serve as a nursery for shrimp and fish, so if our goal is building more land, it stands to reason that we’ll be creating more habitat.

Reducing risk addresses another very important need for coastal areas:  protection from flooding and hurricanes.  This has always been a priority for those who live in Louisiana, and always will be.

Another element CPRA considered is the time it takes to restore our coast and how long projects will last.  Projects that might be constructed quickly may not last as long, while projects that take longer to build may provide more long-term benefits.

Lastly, protection projects for communities were allocated according to population density, with an emphasis placed on reducing annual damages for the largest number of people across our entire coast.  Protection funds were allocated equally between both structural and non-structural protection.

With these criteria in mind, CPRA went through three steps in building its overall strategy for the next 50 years of coastal restoration:

Step One:  Project Identification

Remember when we said we all want to do something about restoring our coast?  Nowhere is that more apparent than in the sheer number of ideas the planning team reviewed when it came to identifying possible projects for the 2012 Coastal Master Plan.  In all, more than 1,500 projects were screened, using the criteria below to whittle down the list.

  • Project redundancy:  if two projects were similar, the more detailed version was moved forward.
  • Project Area:  projects affecting less than 500 acres were not considered because CPRA wanted to focus on large “landscape level” projects.
  • Combination of small projects:  if smaller projects had the potential to work well together, then those projects were combined as a single, larger project.
  • Funded Projects:  projects that were already funded and/or moving ahead into construction were considered to be a part of the future landscape and not evaluated.
  • Inconsistency:  projects inconsistent with the established goals of the master plan were eliminated.  For example, projects which did not have either a restoration or protection feature were eliminated.
  • Diversions:  there were too many varying river diversion concepts for the state to screen each one at this stage.  With input from a partnering Framework Development Team, CPRA established a standard approach for identifying locations, discharges, and flow regimes for a suite of diversion concepts that were then moved forward or not to the evaluation stage.

Step Two:  Project Evaluation

After the first stage of project identification, nearly 400 project concepts remained.

To refine the list of projects even further, CPRA’s planning team ran through a “predictive modeling” procedure, to estimate a project’s performance against a variable range of future possibilities.  The modeling process takes place on a variety of platforms, from a desktop to a supercomputer.  Models help determine the outcome of relationships between variables which affect our coast like sea level rise, storm intensity and frequency, and subsidence.

Each project was run through seven of these models, and considered under scenarios where wetland loss was occurring at a faster or slower rate.  From the data collected in these modeling exercises, a project’s effects were predicted over a 50-year period of time.  The seven models include eco-hydrology, wetland morphology, vegetation, ecosystem services, barrier shoreline morphology, storm surge/waves, and risk assessment.

Interaction of Predictive Models

 

Step Three: Project Selection

With step two complete, the planning team faced a massive amount of technical information about each project and how it might perform in the future.

To create a final list, the team created a “prioritization tool” to assist in sorting through projects.

The tool’s main job was to consider the two most important factors in making a decision about a project:  its land-building and risk-reduction qualities.

After that consideration, the CPRA planning team also looked at many secondary criteria including support of cultural heritage, flood risk reduction across socioeconomic groups, flood protection of historic properties and strategic assets, sustainability, and maintenance costs.

Beyond that, a third set of criteria came into play, including a project’s effects on ecosystem services like habitat for wildlife and fisheries, storm surge protection and fresh water availability.

Conclusion

CRCL recognizes that there is no perfect process to creating a plan of this magnitude, but we are encouraged by the transparency of the planning process and its adaptability.

The list of prioritized projects for each region is also scalable, which means that if the state receives more funding for projects than the estimated $50 billion over the next 50 years, those projects that did not make the final cut could potentially become part of the plan.

The state is targeting its limited resources on projects that will build the most land and reduce risk on the greatest scale, where these benefits have the best opportunity to be sustainable.  This is a responsible way to construct a plan for a future with uncertain levels of funding, unpredictable storm activity and variable rates of land loss.

Our next installment in our Coastal Master Plan 101 series takes a look at the specific strategies used in the 2012 coastal master plan, for all three areas of the Louisiana coast.

To view the official draft of the 2012 Coastal Master Plan, click (here).

 

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