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Monitoring delivers just the facts
Data Perform as Star Witnesses in Project Planning and Evaluation

Cooks know you can’t perfect the recipe if you never taste the soup. Similarly, scientists and engineers know they can’t improve restoration techniques if they never evaluate the results. By monitoring wetland conditions, scientists can determine how effectively restoration projects are rehabilitating Louisiana’s coast and if they are producing unintended, adverse consequences.

To acquire information about wetland conditions, CWPPRA relies on the Coastwide Reference Monitoring System – Wetlands (CRMS-Wetlands). Developed through a partnership with the Louisiana Department of Natural Resources (LDNR) and the United States Geological Survey (USGS) in 2003, CRMS-Wetlands collects biological, chemical, physical and climatological data from 390 monitoring stations located randomly throughout 3.67 million acres in coastal Louisiana. Monitoring guides management LDNR scientists collect data from each monitoring station, where instruments continuously record wetland conditions such as

Another essential measure of wetland health is the rate of land loss or gain. The USGS determines this by analyzing aerial photographs that document changes in the ratio of land to water over time.

Adaptive Management: Plan, Act, Monitor, Evaluate, Adjust, [repeat]

Through a comparison of data from sites without projects — control sites — to data from within project boundaries, results of restoration practices become evident. Data analysis leads scientists to determine how coastal ecosystems respond to diverse influences such as water flow pulsed through diversions, drainage accelerated through control structures or nutrient-laden sediment sprayed in a thin layer over fragile marsh. Accumulations of data permit scientists to discern landscape trends resulting from restoration projects as well as from natural events, and the geographical reach of the monitoring system allows environmental managers to assess the cumulative effects of multiple coastal zone projects.

Managers use the knowledge derived from monitoring to adjust project operations through a process known as adaptive management. CWPPRA continuously improves project selection, engineering, design and construction by applying the lessons learned from evaluating project performance.

Modeling relies on monitoring data

Data collected through monitoring is also used to develop, validate and refine computer models of environmental change. Models of coastal wetlands provide a framework for scientists to explore relationships among physical processes, geomorphic features and ecological succession. The more comprehensive the set of data used, the more accurately modeling can depict the influences on and changes to the actual coastal ecosystem.

In a project’s design phase, engineers may use models to examine and refine different approaches to achieving the project’s goal. Designers can test features through modeling, selecting those that increase a project’s efficacy and reduce construction and maintenance expenses.

Models developed during the design process also provide a tool for evaluating a completed project’s performance. By adding data collected after the project becomes operational, managers can assess how well the project is achieving its goals and adjust management practices to increase its success.

CWPPRA projects withstand 2008 storms

While determining the lasting effects of hurricanes Gustav and Ike on Louisiana’s wetlands won’t be possible for months, teams have already surveyed CWPPRA projects for storm damage.

“In general, inland projects fared well,” says Garrett Broussard, an operations and maintenance engineer with Louisiana’s Office of Coastal Protection and Restoration. “About eight suffered damage that we’ll need to repair.”

But barrier islands were hit harder. ”They served their ecological function,” Broussard says, “but in the process they lost a lot of sand. If the sand has stayed within the barrier island system, we might be able to find it and use it in rebuilding these islands.”

Broussard describes Rita and Ike as similar high-water storms. “After the ’05 storms we noted which construction methods best withstood the storms and where damage tended to occur. It was evident that erosion often occurred at the edges of structures. Rock structures with adjacent abutments held up much better than those without abutments, and we adapted our designs accordingly.”

Scientists collect data in a wetland
Scientists collect data at a remote station of CRMS-Wetlands. Recording periodic measurements of various environmental conditions, the system is developing a bank of information that will guide future restoration practices and wetland management.