Almost 20 fissures have opened up in those two subdivisions, destroying more than two dozen homes since the eruption began May 3.
The executive director of the Island of Hawaii Visitors Bureau told CNN the volcano isn't just the Big Island's No. 1 attraction, "it's the state's No. 1 attraction".
Meanwhile, fissure 17, which opened Sunday morning, remained the most active, said Janet Babb, Hawaiian Volcano Observatory geologist.
The booking pace for hotels and other activities, such as tours for lava viewing, zip lines and glass bottom boats have fallen by 50 per cent. It may also shoot pebbles up to several miles, and dust areas up to 20 miles away with ash.
This is the "first leak we're seeing out of the bucket", Mr Birch said.
Tourism is one of Hawaii's biggest industries and a big part of the local economy.
Since the eruptions began, 37 structures have been destroyed and officials have ordered the evacuations of almost 2,000 people, mostly in the hard-hit Leilani Estates area. Areas near the volcano have been evacuated but the Hawaii Volcano National Park remains open. The U.S. Geological Survey said a recent lowering of the lava lake at the volcano's Halemaumau crater has raised the potential for explosive eruptions at the volcano.More news: Happy 1 month, True: Khloe Kardashian debuts her baby
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"It's down to one gravel road, that's what also pushed us over the edge", said Rob Guzman, who with his husband Bob Kirk chose to leave their home in the Kalapana Seaview Estates subdivision around 3.5 miles (5.6 km) south of Leilani Estates.
But it will be hard to warn residents who may be in the path of such an eruption.
The eruption of lava from Hawaii's Kilauea volcano might have you wondering about Washington state's own volcanoes. To the east of the summit, toxic gas emanating from steaming gashes around 25 miles (40 km) towards the coast added to the danger facing residents, whose escape routes are threatened with closure because of lava flows, officials said.
Christian and Maritza Ricks, who moved to the area from California in April, stopped at the side of the road to watch and listen to the latest eruption.
"In a way, it's kind of exciting to see what's going on and be this close to it", Christian Ricks said.
Two more fissures opened in the last 24 hours, bringing the total to 19.
As a precaution, plant workers last week removed 50,000 gallons of a flammable liquid stored at the site.