The Advertiser's article on beach erosion (Aug. 6) offered a good introduction to the problem of managing our precious beaches.

Ensuring that beaches are here for our grandchildren to enjoy, in the face of rising sea level, and intense development pressure, requires more than simply stopping seawalls and nourishing our beaches with sand.

If we wish to leave a legacy of healthy beaches, we must choose that goal, define the steps to getting there and fund the process. As the dismal data on beach loss and seawall construction in Mike Leidemann's article plainly illustrate, the present system of coastal management is leading us in the opposite direction.

We must implement a legacy beaches program based on purchasing appropriate abutting lands.

Unless we purchase undeveloped coastal lands that are rich with sand, much of the Hawaiian shoreline will look unhealthy in a few decades.

We might choose to continue fine-tuning and slowly improving the present beach management system as we have for years. However, sea levels that have been rising minimally for the past century are rising faster now. This will accelerate coastal erosion, increase the number of vulnerable lands, and threaten more homes and roadways.

We are not prepared to meet this situation. In truth, there is precious little sand for beach nourishment. And what will we say to homeowners requesting a seawall when their homes are undermined by the ocean and the entire family economy is tied up in the land? Sorry, no seawall for you, you'll have to abandon all your assets and join the homeless?

There is 30 percent more carbon dioxide in the atmosphere now than 100 years ago. This greenhouse gas is effective at trapping heat in the lower atmosphere. Researchers report that sea- surface temperatures in 2004 were the third warmest in the past 125 years, land surface temperatures were the fourth warmest, and globally averaged temperatures ranked fourth-highest.

In 2005, the highest global annual average surface temperature in more than a century was recorded. As water warms, it expands, leading to a rise in sea level.

Warming also melts ice. Studies this year have found both the Greenland and Antarctic ice sheets experiencing net loss totaling approximately 70 cubic miles of water per year pouring into the oceans. The rate of melting on Greenland has doubled in the past decade.

Tide-gauge data show that global average sea levels rose 4 to 8 inches during the 20th century. Two satellites mapping the ocean surface now record a rate equivalent to 12 inches a century. This is approximately twice the rate of the past century.

Simultaneous to this increased threat from the oceans, but ironically, coastal land has skyrocketed in value.

Relatively modest ranch-style homes on the beach routinely list for $5 million to $15 million throughout the state. The promise of immense wealth by developing our shores has never been greater, and is compelling strong growth in sectors of the real-estate, architecture and construction industries.

How does our present coastal management system handle this situation? Along the Hawai'i coast, environmental management takes place parcel by parcel through a largely ad hoc system of government permits needed to develop lands that abut beaches. Permit applications to build on coastal lots must follow broad overarching guidelines, but these are not tuned to the coastal resource and do not recognize the complexities of the coastal environment.

For instance, a 40-foot setback for construction applies on rocky shores, sandy shores, eroding shores, stable shores, coastal highways, coastal neighborhoods and every other type of coastal setting.

Worse, we divide the sand-storing dunes from the sand-needing beaches. Dunes are managed by the counties, and beaches are managed by the state. This might work better if the two jurisdictions were truly integrated under one policy. However, that is not the case.

Coastal lots could be arranged to accommodate retreat from an eroding shore, and homes designed to be moved for the same purpose. However, usually we build poured-concrete homes on square lots and ignore erosion until it arrives at our doorstep and it is time to apply for a seawall.

Land use under this model becomes a patchwork affair not oriented to a particular outcome. It is certainly not oriented to beach conservation. We cannot claim to be "managing" our beaches under this system because we are not following a plan.

In fact, there is little true "planning" involved. What we have is a coastal permit processing system, not a coastal planning system. How can we leave a legacy of future beaches without a plan? The answer is that we cannot — and that is why beaches are disappearing.

There have been amazing efforts by agencies that manage our beaches. The new setback on Maui that recognizes annual erosion rates in siting construction is the first of its kind in the Pacific. Recently, the Kaua'i Planning Commission, with full cooperation of the developer, enacted a combination of erosion rates and a broad 200-foot buffer to set back a new resort from the shoreline, thus guaranteeing a long life to public access and a healthy beach.

The Honolulu Department of Planning and Permitting is developing a new database of erosion rates for every beach on O'ahu and plans to use this information in its permitting process. And the state Department of Land and Natural Resources has not permitted a seawall on a sandy beach in nearly a decade, despite very heavy pressure from applicants.

These are strong steps that embrace science as an underpinning to smart land use and abandon the old "one size fits all," unscientific 40-foot setback. However, most of our coastline is already developed, and even stronger steps are needed if we want beaches in our future.

The state and counties have policies emphasizing beach conservation. However, as we see time and time again, the current management system fails to meet the goal of a sustainable environment.

Let's achieve a legacy of beaches with a new planning effort focusing on coastal land conservation that recognizes the following: