“This beach,” says Sam Lemmo, gesturing toward Waikiki, “is almost completely manufactured.” As the administrator of coastal lands for the Department of Land and Natural Resources, Lemmo is the state’s point man for the current renewal. He sees the project as the key to preserving Waikiki Beach, but it’s only the latest chapter in the long engineering history of this fabled waterfront. For nearly a hundred years, landowners have studded the shoreline with sea walls, groins (stone jetties extending from the beach) and crib basins in a futile attempt to hold onto their little bit of sand. Between 1927 and 1930 alone, eleven groins were built along the beach. That temporary solution, though, is part of the ongoing problem at Waikiki.
Chip Fletcher, a coastal geologist at the University of Hawai‘i, points out that the name “Waikiki Beach” is misleading. That makes it sound like a single, contiguous entity, but the shoreline has in fact been divided into sections over the last century. Tara Owens, one of Fletcher’s grad students, has identified seven current compartments: Kaimana Beach, Queen’s Beach, Kapi‘olani Beach, Kuhio Beach, Royal Hawaiian Beach, Gray’s Beach and Fort DeRussy Beach. The names might conjure all kinds of romantic associations, but this segmentation lies at the root of Waikiki’s sand problems. To understand why, you have to imagine Waikiki as it once was, without its groins and sea walls.
Old drawings of Waikiki Beach depict a low, narrow dune backed by marshes and ponds—a kind of thin barrier island. This architecture represents the dynamic relationship between sand and waves. Without human intervention, beaches wax and wane with the seasons. They narrow and expand, move inshore and off, heap up in dunes and spread out in shoals. On a natural beach this ebb and flow is fluid and continuous.
“High waves tend to be seasonal or storm-related,” Fletcher explains. “The waves come in and erode the sand, and the sand will migrate off the beach.” Often this forms a sandbar, which makes the sea floor shallower, causing the waves to break farther offshore, which protects the beach. “Then when the high waves are done,” says Fletcher, “the low, fair-weather waves gradually migrate the sand back onto the beach, and the winds pick it up and rebuild the dunes. Beaches are built by waves; you cannot isolate a beach from waves and expect it to do very well.”
But of course, that’s precisely what all the groins and sea walls along Waikiki Beach have done. “Whatever natural processes that used to exist there have been interrupted,” Fletcher says. Groins are designed to reach out into the sea and interrupt the natural long-shore movement of the sand, but even as sand accretes on the upstream side of the groin, it erodes on the downstream side. So instead of a single long beach stretching from Kaimana to Fort DeRussy, we’re left with a scalloped coast of small, artificial beaches, each slowly starving its neighbor.
The groins, however, might not be the worst of the problem. During storms, when a natural beach erodes, large waves can reach up and take additional sand from the dunes. Fletcher likens this to a bank. “The beach is a sort of checking account, with lots of withdrawals and deposits. But when you have truly massive waves, you need a withdrawal from your savings account: the dune field.” From the very beginning, though, Waikiki’s hotels have been built atop the dunes. Like the groins, the hotels and their sea walls starve the beach of sand.
And there really wasn’t that much sand to begin with; the original barrier island at Waikiki was relatively anemic. Even more astonishing is how little sand there is offshore in Hawai‘i as a whole. There are some exceptions—there are pockets of deep sand at Waimea Bay and Kailua Bay, for example—but typically, most of the sand is sitting right there on the beach. That’s why the reservoir of sand off Waikiki is so valuable.
As Fletcher points out, much of the sand on Waikiki Beach isn’t from Waikiki at all. Over the years, the beach has been renewed countless times with imported sand. A fair amount of that sand, he says, is from Päpohaku, on the west side of Moloka‘i, and some might also have come from Maui. Most of the imported sand, though, was trucked in from other parts of O‘ahu. “Some came from Kahuku,” Fletcher says. “They mined the dunes there up until fifteen or twenty years ago. There was also a lot of sand mining in Waimea Bay in the 1940s, but we’re not sure if any of that went to Waikiki. Most of it went to make lime that they put on the cane fields as fertilizer. But if you go to the Los Angeles area, they have a stretch of beaches there called the Grand Strand. There’s a long bikeway that goes through Venice Beach, Marina Del Rey and Manhattan Beach, and apparently there’s a plaque there that says, ‘Sand from this beach was used to build Waikiki.’”