Yes. An American cargo ship from WWII still sits on the bottom of the Thames with 1400 tons of airplane bombs, and on top of that - hundreds tons of other munitions. Smoke bombs grenades.
About half of the weight of a general purpose bomb is actual explosive. So 1400 tons of bombs would contain about 700 tons of TNT. Or about five percent the power of the bomb dropped on Hiroshima.
So if it all went off at once ...it would make a helluva splash in the water.