Hilo expanded as sugar plantations in the surrounding area created jobs and drew in many workers from Asia , making the town a trading center . A breakwater across Hilo Bay was begun in the first decade of the 20th century and completed in 1929 . On April 1 , 1946 , a 7.8-magnitude earthquake near the Aleutian Islands created a tsunami that hit Hilo 4.9 hours later , killing 160 people . In response , an early warning system , the Pacific Tsunami Warning Center , was established in 1949 to track these killer waves and provide warning . This tsunami also caused the end of the Hawaii Consolidated Railway , and instead the Hawaii Belt Road was built north of Hilo using some of the old railbed
7.8-magnitude earthquake
1946 Aleutian Islands earthquake
Hilo, Hawaii