A dramatic reduction in rainfall has increased the risk of brushfires as the Islands enter the hottest and driest months of the year.

Rainfall is down 60 percent from last year. Heavy rainfall in 2005 prompted a lot of growth that has since died and turned into potential fuel, especially in leeward areas.

"Brushfires endanger lives, property, and cause major traffic tie-ups depending on the area of the fire, not to mention the amount of public safety resources that are diverted from their response to routine emergencies," said Honolulu police Major Michael K.S. Moses, head of the department's District 8, which covers the Wai'anae coast and the 'Ewa plain.

In addition to the unusually dry conditions, officials are concerned about a recent increase in the number of deliberately set fires. Cases of arson on O'ahu rose for the fourth year in a row in 2006.

Arson is a felony. Tougher sentencing laws, enacted last year, state that anyone convicted of arson resulting in the burning of 10,000 square feet of brush may be required to reimburse agencies for putting the fire out.

The provision also makes the parents of a minor convicted of arson liable for any monetary fine or cost of extinguishing the fire.

Another danger that concerns fire officials is careless campers and hikers.

"The majority of the fires have been man-caused," said Wayne F. Ching, fire management officer for the state division of forestry and wildlife. "People need to be more vigilant when they are out there camping and hiking and doing recreational activity.

Ching said his division maintains miles of fire breaks each year. "But even with that, we need people to be more aware of what can happen."

Kevin Kodama, a hydrologist with the National Weather Service, said, "We had some wet seasons so a lot of grass and brush grew and a lot of that is not very green anymore. We aren't expecting substantial relief until October when the wet season picks up again."

Through June 1, there have been 235 wildfires on O'ahu, compared with 625 in all of 2006. However, most of the brushfires tend to occur during the dry summer months still to come. Fires hit a seven-year high of 992 in 2005.

Firefighters last night were dispatched to a small brushfire in 'Ewa Beach off Iroquois Road; the night before they extinguished a brushfire above Waimea Bay that threatened to close Kamehameha Highway because of a burned power pole feared to be in danger of toppling.

"Wildland firefighting is a team effort," said Honolulu Fire Chief Kenneth G. Silva. "The HFD works with numerous city, state, federal and private agencies to prevent and control wildfires. But we need help. We need all citizens to be part of our team and prevent wildfires from starting. We all lose every time there is a wildland fire because part of what makes O'ahu such a special place is gone forever."

There were 580 fires classified as arson in Honolulu last year, up from 547 in 2005, 427 in 2004 and 389 in 2003, according to FBI statistics. That's a 49.1 percent increase over that four-year period.

Moses said police and fire officials met in March to share information and discuss strategies.

"My beat officers have been tasked to be more vigilant and patrol those areas prone to brushfires more frequently," he said.

Reach Peter Boylan at pboylan@honoluluadvertiser.com.