From emergency response to strategic planning: A Kilauea case study
August 28, 2022
When volcanoes erupt, the force of explosions and lava dramatically change the landscape, impacting the geography and the lives of those who live and work nearby. This is especially true on the southern tip of Hawaii, which is home to the world’s most active volcano, Kilauea.
Responding to Kilauea’s 2018 eruptions, federal, state and local organizations swung into action to evacuate and protect residents across an almost 14 square mile area that was covered by lava. One interagency group—which included the U.S. Geological Survey (USGS) Hawaiian Volcano Observatory (HVO), U.S. Army Corps of Engineers (USACE), Federal Emergency Management Agency (FEMA) and the state of Hawaii—teamed up to monitor geographic changes and assess damage during the volcano’s four-month active period, as well as gather more information afterwards to help first responders and scientists model and predict future activity for the enhanced safety of residents.
Flying into an active volcano
In May 2018 lava erupted from two dozen vents around Kilauea, filling Kapoho Bay and extending new land nearly a mile into the sea. Destructive rivers of molten rock consumed Hawaii’s largest natural freshwater lake and covered substantial sections of residential communities.
First responders, as well as local, state and federal agencies, had to quickly figure out the risk to surrounding areas, then evacuate residents and prevent people from going into areas that could be threatened by lava flows. While first responders worked on the ground, the HVO pulled together a team including NV5 Geospatial and GEO1 (now a division of NV5 Geospatial) in a groundbreaking partnership to document an active volcano and assess the situation from above.
Chronicling the landscape impact of an active volcano required innovative use of both existing and new technologies. Airborne remote sensing was the only way to acquire the data safely and economically while calderas were erupting and lava was flowing. In coordination with the National Park Service, our partners at the HVO, local agencies and air traffic controllers, our team flew 11 missions in six days, collecting lidar and imagery over 57 square miles, including the Halema‛uma‛u crater, middle East Rift Zone, and lower East Rift Zone and Pu’Ū ’Ō’Ō lava flow field.
Using a helicopter equipped with a state-of-the-art multi-sensor package—dual Riegl VUX-1 LR lidar sensors co-housed with Phase One iXM RGB and NIR 100MP and Oblique RGB cameras—we had the flexibility and agility required to collect data at a low altitude (500 feet above ground level) under persistent cloud cover. Careful planning ensured that we could collect high density lidar (40-80 pulse/m2) and imagery, while also allowing for real-time adaptations in flight height to avoid lava vents, gas clouds and debris.
Because rapid turnaround of information was critical for real-time response to the eruption, NV5G processed the data within 10 hours of each mission while onsite, then worked with USACE, which provided automated cloud point processing and generated a digital elevation model (DEM) within another 10 hours for immediate analysis by the USGS, HVO and others. With this data in hand, first responders and scientists got unique insights into the rapidly changing conditions to help assess damage and gain key insights into the changes happening.
Establishing a baseline for the future
In 2019, our team joined forces again for a data collection that spanned 219 square miles around Kilauea, nearly four times the size of the survey area the year before. The goal for this project was to document the post-eruption landscape. From there, we’d develop a baseline model that would help predict the geography and topography of future lava flows for the enhanced preparedness and safety of residents.
Once again, we leveraged the latest technology, deploying a unique sensor configuration package to enable increased point density (up to 100 pulses/m2 compared to 40-80 pulses/m2 in 2018), which provided greater detail and accuracy. The customized multi-sensor package included the Riegl VQ-480II (a lightweight sensor with drone capability) with an integrated Phase One IXU RS-1000 4-band camera.
During this project we also conducted a ground survey to determine absolute accuracy, and georeferenced and rectified imagery to new lidar data. From there, we provided our partners and other agencies with a classified point cloud in LAS v1.4, bare earth DEM, intensity images, orthorectified 4-band imagery and metadata.
Comparing data and imagery collected during the 2018 eruption and 2019 baseline program to data collected in 2011 yielded interesting results. We quantified large topographic shifts, finding that some areas had shifted 1.5 meters to the east, 2 meters to the north, and a full 1 meter in elevation in just seven years. Such changes could have a significant impact on structural stability of homes, utility infrastructure and surrounding vegetation, impacting safety of residents. These findings were then confirmed by HVO scientists.
And during our 2019 flights, the GEO1 crew discovered a 10-foot body of water inside the Halema’uma’u Crater—something that had not been observed before. Over time, the pond grew to a depth of 60 feet and spanned more than 600 feet. Between December 2020 and May 2021, the water boiled off and was replaced with a lava lake that was about 700 feet deep. These observations prompted researchers to investigate the volcano’s water table and prepare for the possibility of steam-driven explosions in the future.
Collaborative partnership improves public safety
The collaborative partnership between the HVO, USACE, FEMA, the state of Hawaii, NV5 Geospatial and GEO1 showcased the innovative use of geospatial technology to study active volcanos and improve public safety. The high-profile nature of the 2018 eruption and quick response of the team shone a spotlight on the value of remote sensing, using state-of-the-art lidar and imagery, to support natural disaster response and monitoring. And by collecting even more detailed data post-eruption, we were able to show the impact on the landscape and human infrastructure, providing scientists, first responders, and state and local agencies with valuable insights to predict future lava flow paths that will inform hazard planning and public safety initiatives.
Joel Burroughs, program manager for NV5 Geospatial, has more than 16 years of experience with project management in the federal practice area, with additional experience in energy, transportation, and state and local arenas for contracts ranging in scale from small mapping projects to large regional and statewide programs.
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