'Firehose' lava streams from Hawaii volcano

The lava started to flow into the ocean in a trickle after a 26 acre (10.5 hectare) lava delta collapsed into the ocean on New Year's Eve.

Over the last month the Kilauea flow has increased from a lava tube at the Kamokuna ocean entry on the southeast side of the Big Island. The lava now falls 70 feet (21 meters) into the cool seawater below, causing explosions and billowing smoke.

Kilauea has been erupting continuously since 1983, and the most recent vent flow that is reaching the ocean has been ongoing since last summer.

"We're always watching for what the cliff is doing. Is it moving? Are the rocks rolling down the cliff? We can actually see the changes throughout the day," said tour boat owner Shane Turpin of Lava Ocean Tours. He called the lava flow "definitely the most dramatic firehose event I've ever witnessed in the last three decades of viewing lava."

Explosive collapse?

One of the biggest concerns is a large "hot crack" in the rock above the lava flow, according to United States Geological Survey geologist Janet Babb. The crack is parallel to the sea cliff and makes the surrounding land susceptible to collapse.

"The seaward side of that crack could fall away," said Babb. "That is of great concern because if it does, it's going to drop a lot of hot rock into the water and hot rock mixing with cool seawater makes for explosive interactions."

"There's no indication of it slowing down or stopping," said Babb.

kbd/jm (AP)