I can remember when my husband and I, and our four children, would play touch football on Lanikai Beach in the 1970s. We could walk along the shoreline from the Kailua end of Lanikai all the way to the Waimanalo end of the loop.

That was before shoreline erosion took its toll.

In its present state, Lanikai Beach is cramped — with canoe clubs, fishermen, paddlers, sunbathers and swimmers all crammed onto a tiny stretch of shoreline that is a pittance of what it once was. Swells now slap menacingly against seawalls throughout much of Lanikai, creating backwash and providing an example of what happens when we fail to recognize and address coastal erosion.

Just around the corner from Lanikai is Kailua Beach — a unique jewel within the Hawaiian Island chain, as one of only a few accreting, urban coastlines that is entirely unarmored. Kailua Beach's development history, with large open areas makai of beachfront homes, has allowed the beach and dune system to remain intact and healthy while residential lots have been used to their highest and fullest potential.

This has created a win-win situation where private property owners and the general public each enjoy full use of this beautiful coastline. With erosion beginning to threaten this natural treasure, it is imperative that we act this legislative session to protect Kailua Beach.

The southern (boat ramp) end of Kailua Beach is eroding. This most heavily utilized portion of the beach is eroding at the alarming rate of 2-3 feet per year. The area includes Kailua Beach Park, which is used by large numbers of tourists and local residents alike. The area between the mouth of Ka'elepulu Stream and the Kailua Boat Ramp used to be a wide, sandy beach, where tourists could spend a day picnicking, swimming, or reclining.

That beach is no more. Cinder blocks and rebar - once buried deep under sand - protrude, and waves eat away at the dune system, exposing the roots of pine trees. To make matters worse, the erosion is propagating northward along the beach, toward beachfront homes and the widest areas of Kailua Beach.

For the past year, I've worked together with shoreline specialists from the University of Hawai'i and other government agencies to assess and identify the best course of action in dealing with erosion on Kailua Beach. In analyzing the rates of erosion and northward propagation along Kailua Beach, and the potential for degradation of property values, we determined that an interim moratorium on construction makai of existing structures was in the public's best interest.

Eight other members of the House Committee on Water, Land, and Ocean Resources and I have co-sponsored House Bill 593. The bill establishes an interim coastal construction line that temporarily restricts new construction makai of existing structures on beachfront properties in Kailua. It directs government agencies to assess the resource, giving special consideration to the natural processes of accretion and erosion that are unique to Kailua Beach.

Rules will then be determined regarding shoreline setback and the mauka extent of shoreline conservation districts in Kailua. The bill sunsets upon the adoption of rules, or in 2011, whichever is sooner.

It's important to note that some recent beachfront construction degrades the views of several existing homes and has generated backlash from the public. The makai footprint of one of these homes under construction rests on sand that at one time was under the shoreline surf.

Property values of beachfront homes are largely a reflection of their open view plain, a vista that is enjoyed by the thousands of people who use Kailua Beach for daily recreation. House Bill 593, in addition to protecting the value of existing properties, will prevent new development in areas that may be threatened by the recent erosion problem.

The Kailua shoreline is one of our community's most valuable resources. The wide, sandy beach is not only a community treasure — it is the reason that property values are so high along the shoreline. By supporting House Bill 593, we are preserving a natural resource for community use, and protecting property values for owners of beachside residences, while acting to ensure that this natural resource will be available for future generations.

Rep. Cynthia Thielen represents the 50th District (Kailua-Kane'ohe Bay). She wrote this commentary for The Advertiser.