USGS Preliminary Analysis_LERZ_7-15-18_v1.1

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Figure 4. Map of lavasheds that drain through steepest descent lines (light blue). The numbered lavasheds are described in the text. The grey cross-hatched lava flow polygon is the erupted lava from all fissures as of July 12, 2018. The red line within the July 12 lava flow polygon represents the fissure 8 channel system on that same date. Upper channel (A— B) Any major flow caused by a breach of the west wall of the channel between the vent (A) and the intersection Pohoiki Road and Highway 132 (B) is likely to advance northeast into lavashed 1, hugging the northeast edge of the existing flow. Beyond Highway 132, the flow may enter lavashed 2 and become captured by steepest descent lines that pass along the eastern boundary of the Nanawale Estates subdivision (along Road A and possibly Seaview Road). If the flow continues to advance, it will ultimately cross Railroad Avenue and Government Beach Road, enter lavashed 3, and reach the ocean between 1.3 and 2.3 km southeast of Kahakai Boulevard (Hawaiian Beaches). If the flow enters lavashed 2 and stalls, subsequent lava flows advancing along the west side of the stalled flow could enter lavashed 4 in Nanawale Estates subdivision and ultimately reach the coast slightly closer to the Hawaiian Beaches and Hawaiian Shores subdivisions. Middle channel (B — Q The fissure 8 channel becomes braided northeast of B, with narrower sections that could form choke points. If one of the narrower sections becomes blocked by large collapse fragments from the channel wall or spatter cone, lava could be diverted out of the channel. If, in this scenario, part of the channel is redirected to the north, lava could feed into lavasheds 5 or 6 and threaten homes and infrastructure in the Noni Farms area, Railroad Ave., Papaya Farms Rd., and Government Beach Rd. before entering the ocean between Kalamanu and the northern edge of the 1960 lava flow.