Cliffs along the Hamakua coast are subject to failure and pose a major challenge for development and a major threat to the natural environment. According to geologist John P. Lockwood, Ph.D., in a report regarding the arsenic contamination on Hakalau Point (3/18/2014):
The entire Hamakua coastal area, from north of the Wailuku River to Honokaa, is characterized by a mantling of deeply weathered volcanic ash deposits, known varously as the "Pahala" or "Homelani" Ash, which in turn overlie deeply weathered lava flows from Mauna Kea volcano (Buchanan-Banks, 1983; Wentworth, 1938) ... Wherever mechanically disturbed, however, these ash deposits become structurally unstable (Wieczorek and others, 1982), and are subject to "thixotropic" behavior (ability to convert from stable solids to viscous, mobile fluids when under load pressure or on steepened slopes).
Dr. Lockwood's full report is included in the Final Removal Action Report, prepared by Integral Consulting Group for the Hawai`i Department of Health, dated June 18, 2014.
Further south along the Hamakau Coast, cliff failures in Honolii threaten imminent harm (click here for video news report).
Within our Hakalau Kuleana, from Kolekole to Ninole at the 20 mile marker, cliff failures are a constant threat.
Photos taken in June, 2017 show a cliff failure that could potentially undermine Highway 19 at the 17.4 mile location.
Two cliff failures occurred at Hakalau Point, date unknown, one facing the bay and the other on the makai side.
Photos taken from video posted on www.hanahouhakalau.com
In January 2015, a cliff failure on the North Hilo side of Hakalau Bay resulted in the loss of 5,400 square feet of land and polluted the water with mud and debris for weeks.