A 36-hour spate of heavy rains on O'ahu and Kaua'i last week did little to improve the conditions.

"One rain event doesn't alleviate a drought," said Tom Birchard, National Weather Service forecaster.

Meanwhile, no heavy rain is forecast through this week.

The lack of rain is especially hurting farmers, who are irrigating more to keep their crops alive or losing some crops altogether. In Waimanalo, farmers are also struggling under 20 percent mandatory water cutbacks for use of the state's surface-level irrigation system, threatened with severe depletion because of the dry weather. The system isn't connected to the city's groundwater system, but farmers use it because it is much cheaper.

Using city water can cost thousands of dollars more a month.

Waimanalo farmer Grant Hamachi, who grows radishes, corn and leafy vegetables, is using city water for some of his crops, which has increased the price of farming — a cost he isn't sure he'll be able to pass on to customers on top of increased fuel prices and the other rising costs of farming.

"All crops need water," he said. "You've got to do what you've got to do."

Dean Okimoto, owner of Nalo Farms and president of the Hawaii Farm Bureau Federation, said the sparse rainfall has created another problem, too — more bugs.

"Rain would naturally knock it (the bug problem) down," said Okimoto, who uses a drip irrigation system at his farm in Waimanalo but wants to install sprinklers to mimic rain.

'ABNORMALLY DRY'

This month, 99 percent of the state was classified as experiencing "abnormally dry" conditions, compared with 75 percent a year ago, according to the National Drought Mitigation Center. And in April, typically one of the wettest months of the year, nearly all the rain gauges on O'ahu got below-normal rainfall, with more than half seeing 50 percent of normal.

The lack of rain is especially worrisome on Maui and the Big Island, whose surface-level water systems depend on the annual wet season for replenishment. Parts of the two islands are so dry that the National Weather Service says they could soon develop drought conditions.

And things probably won't get better anytime soon: The state officially entered its dry season this month.

"We've kind of passed the period where we would expect really big rain events," said Kevin Kodama, NWS hydrologist.

From January to April, Kahuku saw just 5 inches of rain, 25 percent of normal levels, Kane'ohe got 2.6 inches of rain, compared with 18 inches in a normal year, and the rainfall total at Makua Range was just 8 percent of normal. On Maui, Kihei saw just 16 percent of its normal rainfall.

And all but four of 24 rain gauges on the Big Island saw below-normal rain.

The sparse rainfall has created what's expected to be a summer of headaches for everyone from O'ahu and Neighbor Island water officials to farmers to firefighters. With no heavy rain in the short-term forecast, many are anxiously awaiting the wet season's return in October. Other than the brief downpour last week, the last extended heavy rains O'ahu saw were in February.

FIREFIGHTERS 'READY'

Fire Capt. Terry Seelig, Honolulu Fire Department spokesman, said firefighters are planning for a busy brushfire season.

"We plan to be ready to respond," he said, adding that firefighters are taking all their usual measures of training and readying equipment to prepare for brushfires.

The danger of brushfires is evident, looking at the dry hillsides on the Wai'anae Coast. Even Diamond Head shows precious few patches of green, and in neighborhoods across the state, grassy expanses are dead or dying.

Kodama, of the National Weather Service, said no single phenomenon is to blame for the dry weather. Forecasters actually went into the wet season expecting a wetter-than-normal year, as more rain is a usual byproduct of a La Niña weather pattern. But the rain never developed.

Water officials on O'ahu are worried because people tend to use more water during dry periods, sapping the resource. Last month, O'ahu residents and businesses used 4.38 billion gallons of water for everything from drinking to watering their lawns. Water consumption is slightly down from a year ago, but higher than in April 2006 — a month with lots of rain, when residents used 4.1 billion gallons of water.

"We're heading into what is typically the dry season, and we're heading into it having had below-average rainfall," said Su Shin, a Honolulu Board of Water Supply spokeswoman. "We're keeping a close eye on all of our sources. This is a good time to remind people to ... conserve."

It won't be long until Maui and the Big Island see water restrictions, said Neal Fujii, the state drought and water conservation coordinator with the Commission on Water Resource Management, of the Department of Land and Natural Resources.

Maui Department of Water Supply officials say they are increasingly worried about the situation in Upcountry Maui, where levels at the three main reservoirs are dropping steadily. On Thursday, the Maui Board of Water Supply asked residents and businesses to voluntarily cut back on water use by 5 percent.

Water in the three reservoirs that serve Upcountry Maui totaled about 91 million gallons in mid-May — or half of their combined capacity.

Upcountry Maui also went through a drought last year. In June 2007, water officials issued a mandatory 10 percent cutback in use and didn't lift the restriction until December.

Central and South Maui residents also are being urged to cut water use.

Big Island residents also are being encouraged to voluntarily conserve. Areas most affected by the dry weather are Waimea Town to Kawaihae, upper Pa'auilo, Ahualoa and districts of South Kohala and Hamakua. Last summer, the areas were under either mandatory or voluntary water restrictions.