About 3,700 bombs were tested, first in New Caledonia and later at Whangaparaoa Peninsula, near Auckland. The testing concluded the weapon was feasible and that a series of 10 large offshore blasts could potentially create a 33-foot tsunami capable of inundating a small city.
Waru said though the testing was positive the project was shelved in early 1945. Experts concluded that single explosions were not powerful enough and a successful tsunami bomb would require about 2 million kilograms of explosive arrayed in a line about five miles from shore. New Zealand authorities continued to produce reports on the experiments into the 1950s.
'Tsunami bomb' tested off New Zealand coast by Jonathan Pearlman, The Telegraph