LIHU'E, Kaua'i — Owners of Kaua'i agriculture and open-zoned lands who hope to build additional dwelling or " 'ohana" units on their land have six months to lock in their rights to do so.

New county ordinance 183 extends until June 15, 2007, the end of a measure that permitted 'ohana units on agriculture and open-zoned lots that normally qualify for just one house. Many residents have used the ordinance to build a second home on the lots, and subdivided the lots using condominium laws so they could be sold independent of the primary residence.

Landowners seeking to take advantage of the opportunity to build the second unit have until June 15 to obtain an additional dwelling unit, or ADU, Facilities Clearance Form, and until Dec. 15, 2009, to receive a building permit for the unit.

The county in 1989 extended 'ohana home rights, which continue to be permitted on residential lots, to agricultural and open properties as a way to increase the island's housing supply. The 1989 ordinance was extended four times. But ordinance 183 suggests that the 1989 ordinance was poor planning from the start.

"By not ensuring that infrastructure would be available to qualifying lots before they were granted the privilege of an additional dwelling unit, the law has distorted the planning process and created a demand for infrastructure that is not in accordance with orderly community development," the ordinance says.

The 1989 measure's loophole would have closed at the end of this year, but real estate agents and property owners petitioned the County Council for an extension, arguing in part that many property owners had not been informed that their right to a second home could be lost.

"In order to mitigate the lack of notice that so many have experienced under the expiring law, the Council reluctantly finds it is appropriate to create a limited right" extending the authority, but warned that any further extensions are considered "detrimental and unwarranted."

The extension does not apply to any lot created after the end of 2006, or to lots created through moving a kuleana property.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.