Rising Sea Level Taking a Toll on Maui’s Shoreline

“Our coastal ecosystem and our development are on a collision course.”

January 30, 2014

Celeste Keele - Contributing Writer , Maui Weekly

After the holidays and the annual, year-end, members-only party, the Kihei Community Association (KCA) is back in action. January's meeting (meetings are held on the third Tuesday of each month, open to members and nonmembers alike) started the new year with an informative hour-and-a-half studded with facts and discussion of a timely concern--coastal erosion. Maui's coasts are eroding, and will continue to erode a lot more in the next century as ocean levels rise. So how long can we populate the dynamic coast, what do we do about property and infrastructure already there, and how do we take care of our beaches and dunes long-term?

There to explain the problems and possible solutions were Coastal Geologists Tara Owens, coastal hazards specialist with the University of Hawai'i Sea Grant College Program and a liaison to Maui County, and Jim Buika, Maui County's coastal resource planner.

So what's the problem? Through the years, Maui leaders, like those of other islands, chose to build roads and houses and buildings right on the coast.
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“Our requirement is to protect our coastal ecosystem and protect our development, too,” said Jim Buika, Maui County’s coast-al resource planner.

Tara Owens, coastal hazards specialist with the University of Hawai‘i Sea Grant College Program, explained the difficulties of managing coastal erosion.

We are doing a “very, very good job in South Maui with dune restoration,” said Tara Owens, coastal hazards specialist.



"Our coastal ecosystem and our development are on a collision course," explained Buika.

Our beaches are being eaten away by erosion and by secondary influences, such as sea walls, which were built to protect homes and condos. Meanwhile, our roads and houses are being threatened by the encroaching ocean.

As Owens said, "We generally can't protect both our personal property and the beach," but that's what we are attempting to do.

Sea walls are being undermined and many new ones are being built. All of them create a domino effect, protecting a few homes or a condo complex, and forcing the ocean's mass onto the beaches on either side, rapidly speeding up erosion and ruining other beaches.

Halama Street in Kihei is a good example of the domino effect, the geologists explained. Once homeowners start building sea walls, almost everyone eventually has to, as their beach and dunes start to erode because of the waves rolling around the sea walls.

"Maui has lost more than four miles of sandy beach in the past century, and we're going now to lose another mile," said Buika.

Owens gave the example of Sunset Beach on O'ahu, an iconic beach that is disappearing. She showed photos of homes just about to fall into the ocean. These houses were built on coastal dunes, the only thing that supplies a beach with sand and protects it from erosion, explained Owens.
The state gave homeowners permission to push around sand to shore up house foundations, but as Owens pointed out, it's just a matter of time... Long-term, these homeowners will most likely ask for a sea wall, a cost-effective but shortsighted and hazardous solution. What happens with O'ahu's coastal erosion crisis will be a litmus test for the future of the problem on the other islands, including Maui. And Maui's beaches are experiencing the fastest erosion of the Hawaiian Islands, with the highest percentage of beach loss--11 percent.
Humans are partially responsible for this erosion through sand mining and building artificial sea walls. Currents and wave conditions are other factors. And lastly is the much-discussed rising of sea levels. (Go to www.csc.noaa.gov/slr/viewer/ to use an interactive graphic that illustrates how rising sea levels will affect American coasts.)
Scientists estimate that sea levels will rise one foot by 2050 and three feet by 2100, said Owens. Hawai'i's sea level has risen six inches (more for Maui) over the past century, and is already threatening a lot of property damage.
"A one foot vertical rise will cover a long distance horizontally," Owens warned.
What are our response options? First, we can do nothing and let the houses fall into the sea (some audience members liked that). We can continue to build sea walls. We can build elevated homes. We can take on more beach management and dune restoration (of which Maui is leading the charge), and we can sand bag and sand push. We can also set up a managed retreat, like the newer setback rules for building near the shoreline.
Buika insisted that we need to make beach management and beach nourishment more cost-effective. People want a sea wall to protect their property because it's a cheap option. If the state subsidized better long-term solutions, people would choose those, he explained. We need to stabilize the beaches, create access for people (like dune walkovers, already successful at Kama'ole Beaches I, II and III), and protect and rebuild the dunes, explained Buika.
Other ideas included protecting the sand we do have, both inland and on the coast. For example, inland sand dunes are scattered across the island. When a development comes in and builds a shopping center, they ship that Maui sand to Honolulu for transformation into concrete for buildings on O'ahu. Buika proposed that we enact laws to protect our existing sand and to stop deportation as soon as possible.
There's also an idea circulating about government land acquisition and land buyouts, so we can start moving buildings and infrastructure and re-ordering our island.
As it stands now, with buildings and roads right on the water and coastal erosion only increasing, "We have sort of a management nightmare right now," said Owens.
To volunteer to help nourish beaches and dunes, visit www.southmauivolunteers.com.
The next KCA meeting is Tuesday, Feb. 18, starting at 6:30 p.m., at Kihei Charter School, 41 East Lipoa St.

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