Cordilleran Section - 113th Annual Meeting - 2017

Paper No. 55-7
Presentation Time: 3:35 PM

RESPONSE TO EFFUSIVE BASALTIC ERUPTIONS IN URBAN ENVIRONMENTS: LESSONS FROM THE 2014-2015 PAHOA LAVA FLOW CRISIS


TSANG, Sophia W.R.1, LINDSAY, Jan M.1, WILSON, Thomas2, NEAL, Christina3, STEWART, Carol4, WALLACE, Kristi L.5, LEONARD, Graham S.6, DELIGNE, Natalia Irma7 and KENNEDY, Ben2, (1)School of Environment, University of Auckland, Auckland, 1010, New Zealand, (2)Geological Sciences, University of Canterbury, Christchurch, 8140, New Zealand, (3)US Geological Survey, Hawaiian Volcano Observatory, PO Box 51, Hawaii Volcanoes National Park, HI 96718, (4)Joint Centre for Disaster Research, Massey University, Wellington, 6140, New Zealand; GNS Science, Lower Hutt, 5040, New Zealand, (5)Alaska Volcano Observatory, U.S. Geological Survey, Anchorage, AK 99508, (6)Joint Centre for Disaster Research, GNS Science/Massey University, PO Box 30 368, Lower Hutt, 5040, New Zealand, (7)GNS Science, Lower Hutt, 5040, New Zealand, stsa972@aucklanduni.ac.nz

Volcanoes have long disrupted urban environments through a range of volcanic hazards including tephra, gases, pyroclastic density currents, lahars, and lava flows. Relatively few of these disruptions to inhabited areas have been caused by lava flows; examples include lava flows from Mount Vesuvius inundating Massa di Somma in 1872, from Eldfell inundating Heimaey in 1973, from Kīlauea inundating the Royal Gardens subdivision beginning in 1983, from Nyiragongo inundating Goma in 2002, and from Fogo inundating Portela and Bangaeira in 2014-15. Partially because such occurrences are rare, few lessons regarding the best preparation for and mitigation of lava flow inundations have been gathered. However, as the populations around volcanoes grow, the potential economic losses from such events in the future are increasing. It is therefore timely to collate lessons from lava flow inundations from around the world and use this information to inform mitigation efforts.

In 2014-2015, pāhoehoe lava flows from Kīlauea encroached upon the town of Pāhoa on the Island of Hawai’i. The township’s solid waste transfer station, a Hawaii Electric Light Company power pole, two residential structures including a shed and a house, and a secondary roadway were burned or inundated by the lava flows. Overall, the lava flows reached little infrastructure and few buildings, but the threat of the lava flow triggered temporary relocation of students to other schools, business continuity plans for many local businesses, and significantly impacted the fabric of the community and the lives of thousands of individuals who faced months of uncertain lava flow advance. Two years after this crisis, we have conducted interviews and focus groups with scientists, emergency managers, and personnel from the local utility companies who responded to the events. We present preliminary findings on the effectiveness of mitigating actions taken during the event and explore how best to respond to a similar event in the future in Hawai‘i and elsewhere. The data collected from these interviews and focus groups will inform impact assessments and the development of mitigation strategies in other urban areas that could be threatened by effusive basaltic eruptions in the future, such as Auckland, New Zealand.

Handouts
  • Tsang Presentation upload.pdf (1.0 MB)