What does Revelation 8:10 mean?

The second trumpet marked massive corruption of the seas: the salt waters of the earth (Revelation 8:8–9). This causes monumental death, destruction, and hardship. The result of the third angel's trumpet is something John describes as a great burning star, falling from heaven, affecting a third of the rivers and springs of water. This object, too, may be a meteor that burns upon entering earth's atmosphere and causes widespread pollution. Others speculate that this might be a reference to a nuclear explosion which contaminates fresh water supplies. The Great Lakes in the USA, for instance, are a series of connected bodies holding more than 1/5th of all the world's fresh water; their loss would devastate the world.

Regardless of exact details, the target of this judgment is the water supply. People get their drinkable water from rivers and reservoirs. These capture melting mountain snow and rain, but with one third of the water supply adversely affected by the burning meteor many people will perish. Undoubtedly, there will be mass drilling for water in the region affected by this third trumpet judgment, but these efforts may well fail. When God turned the Nile to blood, "all the Egyptians dug along the Nile for water to drink, for they could not drink the water of the Nile" (Exodus 7:24). This trumpet judgment, however, affects more than a single body of water, so it might be that attempts to access underground springs will be thwarted. As we learn from Revelation 8:11, the falling blazing star poisoned the water supply. This is another judgment that earth will experience in the tribulation.