Tides to Storms Project Will Help NH Seacoast Communities Prepare for Floods

From Tides to Storms Project Begins
Story by Kirsten Howard

Riverview Terrace at Hampton Beach was just "river terrace" at 12:17 p.m. during the highest tide of the year on Oct. 11, 2011. Photo by Amy Kane

Riverview Terrace at Hampton Beach was just “river terrace” at 12:17 p.m. during the highest tide of the year on Oct. 11, 2011. Photo by Amy Kane

“With some good information and a little Yankee Ingenuity, communities can do a lot to prepare for coastal floods and sea level rise,” Julie LaBranche, a senior planner with the Rockingham Planning Commission (RPC), told the 30-plus attendees at the recent Tides to Storms kickoff meeting. The From Tides to Storms project (website coming soon) is a two-year endeavor to provide seven NH communities along the coast from Portsmouth to Seabrook with the information and tools they need to take real steps to prepare for the next big coastal storm. Utilizing new LiDAR data (high resolution map data created with an airplane and light-detection sensors), Rob Pruyne of the RPC and Boston-based consulting firm AECOM are creating maps that show where the NH coast would flood under different sea level rise and storm scenarios. The flood scenarios will be based off of the Piscataqua Great Bay Climate Change report by Carbon Solutions. Considering that the best topographic data previous to LiDAR were 25-foot contours, these new 2-foot contour maps promise to be more accurate and informative than any similar efforts done previously.

Lobster shack next to Geno's Restaurant on Mechanic Street in the South End of Portsmouth at the highest tide of the year in October 2011.   Photo by Tim Hayes

Lobster shack next to Geno’s Restaurant on Mechanic Street in the South End of Portsmouth at the highest tide of the year in October 2011.
Photo by Tim Hayes

Once the flood scenario maps are available, LaBranche and other RPC staff will work with coastal NH communities to assess their vulnerable spots–helping them identify infrastructure and utilities, natural resources, transportation systems, and critical facilities that would be at risk if a big storm hit tomorrow and if sea level rise continues to accelerate over the next 50 years. Whether it’s a wastewater treatment plant, school, or roadway, RPC planners and local officials will then come up with tangible actions communities can take to protect those key sites.The public project kickoff meeting at the Hampton’s Lane Memorial Library was attended by coastal watershed residents, elected officials, and planners alike who provided valuable suggestions to the project team. Participants engaged in a vigorous discussion about both the importance of this project and how to communicate the results from the mapping analysis so they can be as useful as possible as towns consider taking proactive action.

LaBranche emphasized that communities can save money long-term by taking action now to protect vulnerable resources before they’re damaged in the storms that scientists expect to become more intense as the climate changes. “There’s a statistic–for every one dollar spent on proactive hazard mitigation measures, society saves four dollars. It just makes sense.” That information comes from a 2005 report by the Multihazard Mitigation Council.

Look for the From Tides to Storms project on the NH Stormsmart Coasts website soon! In the meantime for more information contact Julie LaBranche at jlabranche@rpc-nh.org or 603-778-0885.