Two groups yesterday filed a lawsuit against the state Board of Land and Natural Resources, seeking a change in the way shoreline boundaries are determined, although state officials say they are already responding to those concerns.

The issue affects shoreline property owners but also can affect the beachgoing public, since poor decisions can result in a loss of access along the beach and loss of a sandy beach on which to sit.

Earthjustice filed the suit in 1st Circuit Court in Honolulu, representing the Sierra Club Hawai'i chapter and PASH, Public Access Shoreline Hawai'i.

"PASH remains hopeful that the ongoing efforts to reform the shoreline certification process and setback laws will produce real progress to the benefit of the public. In the meantime, we must work together to stem the tide of beach loss by all means possible," said the group's president, Isaac Harp.

"Hawai'i has a proud history of ensuring public access for all to beaches and shorelines, but the rules being applied today frequently certify the shoreline too close to the water, creating a tangible loss of the public's resources," said Jeff Mikulina, director of the Sierra Club in Hawai'i.

That may have been the case in the past, but the issue has been addressed and is continuing to be fine-tuned, said Sam Lemmo, administrator of the state's Office of Conservation and Coastal Lands.

"We have a new system, as of about a year ago," he said.

Today, any shoreline certification is reviewed by four agencies: the state surveyor's office; Lemmo's office; the Department of Land and Natural Resources' Land Division; and the Sea Grant program at the University of Hawai'i.

The Earthjustice suit argues that the state has, in many cases, improperly focused on the coastal vegetation line as an indicator of the shoreline, even when the debris line left by waves is well inland of growing plants. Some landowners have used irrigation and fertilization to encourage plants to grow toward the ocean, covering more of the beach.

Certification of the shoreline is important to landowners, because it is the seaward boundary from which building setbacks are measured.

Structures built too close to the beach are at risk during high surf or coastal erosion, and many owners have claimed the right to build seawalls to protect their homes.

As many as a quarter of O'ahu beaches and a third of Maui beaches are estimated to have been so armored. In some cases, that means waves lap right up against a wall, removing any sandy beach for the public.

Earthjustice says language in the land bureau rules allow the debris line to be used as a shoreline indicator only when there is no vegetation, creating "an absolute preference for the vegetation line."

Lemmo said that in practice, the department is using a broader view and it is no longer "as simple as just looking at the vegetation line."

He also said that under a mandate from the Legislature this year, a coastal working group has been established to study alternatives.