After Hurricane Sandy: Getting Coastal National Parks Storm-Ready With Elevation Data

Hurricane Sandy hit the U.S. Atlantic coast on October 29, 2012, causing more than $50 billion in damage across 24 states and striking hard at the natural resources and infrastructure of coastal national parks.

Peter August uses a laser rangefinder to measure the distance to an object in the field. NPS.

Soon after, Peter August — a University of Rhode Island (URI) professor of natural resources science specializing in geographic information systems (GIS), who had worked with the National Park Service (NPS) for over 20 years — asked park managers how he could help. Everyone, he recalls, wanted to know how bad the damage was and what had been lost.

Parks in the dark

• Few people could get into the parks: pavement had buckled, bridges were unsafe, and wind and surge had dumped huge amounts of sand and debris on roads and parking lots.
• Gasoline, electricity and internet were scarce, and essential data managers needed had been destroyed by floodwater.
• Emergency crews new to the parks tried to help, but they and park managers lacked a common language of geography.
• Information poured in from communities, counties, states and federal agencies, but with no procedure for gathering and making sense of it, even documenting the damage was hard.

Part of Gateway National Recreation Area before (left) and after (right) Hurricane Sandy, from the NPS Hurricane Sandy Incident Management Team. NPS.

August had founded URI's Environmental Data Center (EDC), whose team created the first GIS data for several parks in the NPS Northeast Coastal and Barrier Network about twelve years before Sandy, so he knew what each park could handle — and he felt their distress when the storm struck.

After the storm, conference calls of up to 25 people — NPS regional and park staff, other federal agencies, affected states and university scientists — tried to keep up. A barrier would blow away and someone would ask whether anyone was mapping it, taking aerial photographs, or recording where and when the breach formed. Breaches — breaks in barrier islands that let ocean and bay water flow together — change daily, even hourly, and managing them takes reliable geospatial data: LiDAR, high-accuracy elevation maps, current aerial photography. The Park Service doesn't fly its own aircraft for such imagery, August notes, so it needs to know who collects the data, in what form, and how to turn it into something useful.

Where a path once ran, a breach opened in Jamaica Bay, New York. NPS.

Three parks

In 2014, EDC began elevation mapping and data management projects with three parks badly hit by Sandy. None, since they were established between 1964 and 1972, had faced a storm so powerful.

The work was paid for by the Department of the Interior's $300 million post-Sandy mitigation initiative, meant to prepare coasts for more frequent powerful storms, sea-level rise and other climate change effects. August expects the lessons to apply to all coastal parks.

August collects elevation data at Fire Island National Seashore. NPS.

What's at risk?

Elevation is the key to knowing which places, structures and resources a future storm would reach. August's central question: if a storm like Sandy came again — say a Category 4 at high tide — would a given building stay wet or dry? Asking is common sense; answering is hard.

Before Sandy, coastal parks had little to support elevation surveys or accurate inundation models — maps of where water would go in storms of different kinds, showing whether buildings, roads, power lines, bridges, archaeological sites or natural resources would need protection, be safe, or go under water. So the EDC team installed new geodetic benchmarks — permanent brass disks marking points whose height above sea level is precisely known — and, with survey-grade GPS bought with the mitigation funds, took elevation readings accurate to within centimeters, for models managers can use for years.

Dunes and beach at Fire Island National Seashore. NPS.

"Standalone capable"

Information from the NPS itself, and from communities, counties, states, agencies and universities, is useless in a storm if it is scattered, inaccessible or disorganized — and after Sandy, with power and internet gone, an avalanche of new information had to be fitted to NPS systems and standards.

A second EDC team therefore built a data management system for the three parks: it found out what critical information they need, tracked down useful data sets, and organized, formatted and secured them so managers can find their way easily, with standard procedures to keep it going. The aim of both projects was to make the parks "standalone capable" in a catastrophic storm, with local access to all their elevation maps, inundation models and LiDAR. Park staff have already tested the prototypes, and August believes that if a Category 3 hurricane hit tomorrow, the parks would be better prepared than ever.

Sources

Based on Jamie Remillard and Caroline Gottschalk Druschke (SEAcomm, University of Rhode Island), "After Sandy, National Parks get storm-ready," National Park Service, Northeast Coastal and Barrier Network; a work of the United States government in the public domain; rewritten in hubnx's own words. A photograph credited jointly to the NPS and URI's Environmental Data Center is not reproduced, and the source's link for Gateway, which points to Assateague, is left off.