WAILUKU, Maui — Maui residents and businesses will experience higher water and sewer rates when the county's fiscal year 2007-2008 budget takes effect today.

County officials said the increases are necessary to keep both utilities self-supporting without subsidies from the general fund.

Under the new rates, the bimonthly water bill for an average household using 30,000 gallons will increase by $5 to $82.50, a 6.4 percent hike.

The maximum monthly sewer charge for a single-family home will rise to $46.65, which is an increase of $8.40, or 8 percent.

Department of Water Supply director Jeffrey Eng said water rates were restructured to have the least impact on low-income residents, who typically consume less water, and on farmers, who have been encouraged to play an increasing role in diversifying the county's economy.

Along with increases in monthly water service charges, water usage rates are rising at most levels.

While residential consumers will continue to pay $1.55 per 1,000 gallons for the first 10,000 gallons, second-tier rates for each 1,000 gallons above that will increase to $2.60, a 20-cent jump.

Also under the new rate structure, the second tier of water usage will cover 10,001 to 30,000 gallons instead of up to 25,000 gallons.

Water consumption at the third tier, usage beyond 30,000 gallons, will be charged at a rate of $3.50 per 1,000 gallons, a 66-cent increase.

Eng said officials hope the much higher third-tier rates will encourage water conservation.

Agricultural users will pay the same first- and second-tier rates of $1.55 and $2.60 per 1,000 gallons that residential customers pay.

But after 30,000 gallons, agricultural usage rates will increase only a nickel to 90 cents per 1,000 gallons.

Nonpotable-water users, namely tenants in the county's Kula Agricultural Park, will pay 90 cents per 1,000 gallons for all levels of usage, also just a 5-cent increase.

Eng said the new water rates are expected to generate approximately $6.7 million in extra revenue for the Department of Water Supply, which is needed to offset higher costs for electricity, operations and maintenance.

New sewer rates put the maximum monthly charge for multifamily units at $38.10, an increase of $6.60.

The flat monthly rate will increase from $29 to $35.25 for residents hooked up to private systems on the island of Lana'i; in Ka'anapali and Kapalua on Maui; and in Kualapu'u on Moloka'i.

The charge for cesspool pumping will rise from $390 to $456 per call, for up to two calls a year.

Higher sewer rates also will affect nonresidential customers, with various fee structures established for hotels, churches, government operations, restaurants and other commercial interests.

Also starting today, the county's sewer system will be placed in the hands of the new Department of Environmental Management.

Reach Christie Wilson at cwilson@honoluluadvertiser.com.