CRMC developing storm damage predicting tool

Say it’s a “powerful” resource
Fri, 02/19/2016 - 10:30am

The Rhode Island Coastal Resources Management Council (CRMC), along with the University of Rhode Island’s Coastal Resources Center (CRC) and Rhode Island Sea Grant, are working to develop a risk index tool that could be an accurate determinant in predicting the environmental impact and damage to the state’s shoreline before a storm occurs.

The new tool, which is the first ever of its kind in Rhode Island and being developed jointly by the CRMC and CRC, is the latest Shoreline Change Special Area Management Plan (Beach SAMP) resource called the Coastal Environmental Risk Index, or CERI.

The CRMC said through a press release that the CERI index tool, created for Beach SAMP by its research team, “will provide an objective, quantitative assessment of risk to both structures and infrastructure from storm surge and waves in the presence of changing climate conditions, in particular, sea level rise.”

“Rhode Island planners and managers will have another tool in their arsenal – in addition to the recently-introduced mapping tool, Stormtools — to utilize in making decisions based on storm events to anticipate risk to infrastructure, property, and emergency services along the coast. CERI uses the Stormtools surge and wave maps, and the Beach SAMP shoreline change maps as a foundation, as well as data from the U.S. Army Corps of Engineers, North Atlantic Comprehensive Coastal Study (using recent data from Superstorm Sandy).” 

“It’s an incredibly powerful tool that we’re working on,” said CRMC Executive Director Grover Fugate during an interview with The Block Island Times. Fugate noted that the CERI index tool will allow the CRMC, and planners, to, in essence, “see into the future” and “predict damage” to coastal structures.

“I’m excited” about it, said Teresa Crean, a Coastal Community Planner and Coastal Management Specialist at the CRC and project manager for Beach SAMP. “It is an effort to assign a risk value to each segment of shoreline in our pilot municipalities. The focus of CERI is on accommodating and protecting our coastal structures.”

“It will be valuable in telling us how structures will fare from a storm before a storm occurs,” said Fugate. “It gives us a ‘what if’ capability that we’ve never had before. It will be capable of predicting what the damage could be, and what can be done to prevent it. And it will estimate damage and provide us with a cost benefits tool.”

“It’s kind of like looking into the future,” said Crean, who is a self-admitted “map nerd” and noted that on Tuesday, Feb. 9 that the tide along the Rhode Island coastline was two-feet higher than predicted. “It’s an interactive tool that we’re tailoring to appeal to different audiences.”

Fugate explained that CERI is an online (Geographic Information System) GIS-based tool that assesses the risk to structures and infrastructure in the event of storm surges, including flooding and waves, taking into account sea level rise and shoreline erosion and/or accretion. Fugate said that it calculates “percent damage for structures and infrastructure” associated with storm flooding, as well as inundation, waves and erosion, and combines all of these factors for a total assessment.

Crean said that the CERI index tool uses the Stormtools and the U.S. Army Corps of Engineers Sea-Level Change Curve Calculator data sources to come up with its conclusions.

New Shoreham GIS Specialist/Town Planner Alison Ring told The Times that, “Stormtools is an effective online mapping tool for planners, which identifies areas at risk to coastal inundation and sea level rise. This tool is helpful for communities to identify infrastructure such as roadways and critical facilities, which may be impacted and to begin planning and mitigation activities. The town of New Shoreham has utilized this mapping tool recently to inform the Hazard Mitigation Plan and Comprehensive Plan updates.” 

“The CERI risk tool, while not available yet for Block Island, appears to expand upon the Stormtools mapping effort and calculate the percentage potential damage to structures, which could assist the town in prioritizing future mitigation efforts,” added Ring.

Fugate said that the Beach SAMP team plans to apply CERI to Narragansett Bay in Warwick, and the southern coastline in Charlestown in a HUD-funded pilot study, with plans to extend the pilot to all of Washington County if and when funds become available.

“Right now it’s a proof of concept project in two coastal communities in the state,” said Crean. “The intent is for it to be expanded to all 21 of the state’s coastal towns. But that will depend on funding.”

A proof of concept is a test, study or demonstration of a certain method or idea to demonstrate its feasibility, and whose purpose is to verify that a concept or theory has the potential of being used in practical application.

According to the CRMC press release, “As a test for the performance of CERI, the index has been applied to the eastern end of Matunuck Beach, which has one of the highest erosion rates in the state.” Researchers at URI noted that “the area is characterized by high density, single-story homes, a few elevated residences (using pilings), and several coastal businesses – a typical mixture of structures for the southern coast of the state.”

The test determined the damage to “individual structures for the 100-year return period storm surge (the likeliness of a storm of this magnitude is once every 100 years, by definition), with and without sea level rise.” As a result, the CERI index “shows that the damage to the single-story homes in flooded areas is extensive, with elevated structures sustaining significantly less damage. Wave damage is rampant in areas close to the shoreline, where storm wave heights are large, while inland areas sustain the most damage from inundation.”

Crean said that “Beach SAMP was created primarily as a mapping tool to help Rhode Islanders understand risk. Now it’s evolving (with CERI) into what kinds of solutions can we offer coastal property owners to address the risks to their properties,” she said.

Crean noted that the Matunuck Beach proof of concept study conducted by URI students determined the different percentages assigned to structures related to predicted storm damage. The study assessed “damage to structures on an individual building-by-building basis” so that a total damage estimate, or forecast of damage, based on percentages, could be assigned to structures, she said.

Crean said that there are three phases associated with the CERI risk index tool: protection, accommodation and relocation, or managed retreat, of at-risk coastal structures and properties. She said that while CERI can be valuable in educating and informing the public about potential property damage, or risk, the information is “sobering” for coastal property owners.

“The challenge will be trying to help coastal property owners make the best decisions about their properties while addressing the risks,” said Crean. “Mother nature usually wins.”