State lawmakers are considering several bills designed to encourage agriculture businesses to preserve their farmland and resist the urge to sell it to developers.

One of the broadest incentives is a 100 percent income tax credit for expenditures on cultivation and processing equipment, water systems, roads, utilities and housing for laborers as long as more than half of the land a business owns, leases or uses is designated "important agricultural land."

Two forms of the so-called agricultural business tax credit — House Bill 902 and Senate Bill 1221 — appear headed for passage. This incentive is estimated to cost about $120 million over six years.

Another advancing bill, HB 1639, makes rental income from important agricultural lands not taxable for income and general excise tax purposes. Estimated six-year cost: $2 million.

SB 1877 would provide a 100 percent state credit for county property taxes paid on important agricultural lands. Estimated cost (in the sixth year): $11 million to $14 million.

Potentially helping farm businesses borrow money are HB 401 and SB 662, which would allow the state to guarantee loans that provide a below-market interest rate for projects on important agricultural lands. Estimated six-year cost: $10 million.

One of the more tested incentives being considered is the purchase of development rights, or deed restrictions. SB 1756 proposes that landowners could sell the state rights to their important agricultural land that guarantees no one could develop the property for nonagricultural purposes.

The Department of Business, Economic Development & Tourism said 27 states have similar programs that have protected 1.5 million acres at a cost of $2 billion.

Under the Hawai'i proposal, a landowner after 30 years could seek to buy back development rights if farming is no longer viable. The bill, however, doesn't appropriate any money for purchasing rights.

Several bills related to important agricultural lands have not advanced, including two that would give important agricultural lands higher priorities for obtaining water.

The water bills, HB 407 and SB 658, were the top priority for the Hawai'i Farm Bureau Federation, but didn't get an initial hearing.

A broader bill giving a 100 percent tax credit to investors in agricultural businesses — HB 901 — also did not advance. This bill's estimated six-year cost is $160 million.

Also dying were bills that would have imposed a moratorium on Land Use Commission decisions to reclassify agricultural land for other uses until the protection program is implemented.

Reach Andrew Gomes at agomes@honoluluadvertiser.com.