Using this same scale, preliminary estimates of lava-flow hazard zones on Maui made in 1983 by the U.S. Geological Survey rated the summit and southwest rift zone of Haleakala as Hazard Zone 3. The steep, downslope areas of the Kanaio and Kahikinui ahupuaʻa and the area north of Hana are rated as Hazard Zone 4. Other areas of Haleakala are rated comparable to the lava-flow hazards of Mauna Kea and Kohala (Hazard Zones 7 through 9).