Hawaii's beaches are infamous. The sparkling sands here attract around 7.5 million people a year who spend nearly $13 billion on their lodging, food, and souvenirs. But this bustling industry is under siege, as Hawaii's beaches are shrinking dramatically every year.
Already, estimates published in 1997 found that ~24% of Oahu's sandy shores had been lost. Now geologists warn that the other islands are shrinking, too - up to 70% of Kauai's beaches may be eroding, with Maui's shores in hot pursuit. It's not just hawaii's problem. Experts have estimated that 60% to 80% of the nation's shoreline is chronically
eroding, but Hawaii's economy is so dependent on healthy beaches that the loss of shoreline here is a much bigger deal.
A huge part of the problem is that Hawaiian homes and businesses were built right on the water. When walls or other shoreline structures are built, it prevents the beach from gaining sand from the land. Called "hardening the shoreline," these structures actually increase the rate of beach erosion because they prevent natural cycles of growth and retreat of beach sands. Naturally, higher waves are buffered by a shifting of sands from the beach and its dunes to further offshore, temporarily shortening the beach. But when a seawall is present, it doesn't allow for sand from the land to replenish the shifting beach, and it intensifies the strength of the waves, leading to erosion. Although the walls might initially protect property, they often result in beach loss and chronically eroded shores.
But even without the coastal development, Hawaii's beaches would be crawling slowly inward in response to sea levels that have been rising since the 19th century. As climate change threatens even higher sea levels in the future, Hawaii's beaches are only going to get smaller.
The state is torn about what to do with its shrinking coastlines. Already, the state and hotels have spent over $3 million pumping in sand from offshore to preserve the width of Waikiki beach, a tourist hot spot. However, the cost to do so to all of Hawaii's beaches would be astronomical.
It's not just about the tourists, either. Hawaii's beaches are critical habitat for the highly endangered Hawaiian monk seal and other native flora and fauna, like the green sea turtle. And as more beaches are lost to the sea, more tourists will move into beaches that had been largely ignored by them, causing even more habitat loss and disturbance for these creatures. The beaches also act as natural buffers to prevent property damage from storm waves, and as these beaches narrow, waterfront areas become increasingly at risk to damage.
The state is considering a radical plan of buying up the waterfront land and demolishing the buildings there to allow the beach to retreat naturally. However, again, the cost of such an initiative will be high, especially with space at such a premium on the islands. Not many are going to be so eager to see their waterfront properties demolished.
Already, beaches like Lanikai and Ewa are likely too far gone to be saved, and they're lined with seawalls that just exacerbate the problem. Whatever the government is going to do, they'd better figure it out sooner rather than later. Hawaii's beaches are disappearing, and before we know it, there won't be much left to protect.
References
1. Charles H. Fletcher, Robert A. Mullane and Bruce M. Richmond (1997). Beach loss along armoured shorelines on Oahu, Hawaiian Islands. Journal of Coastal Research, v.13, no. 1, pp. 209-215.
2. State of Hawaii Financial Facts <http://hawaii.gov/dbedt/info/economic/library/facts/state>
Already, estimates published in 1997 found that ~24% of Oahu's sandy shores had been lost. Now geologists warn that the other islands are shrinking, too - up to 70% of Kauai's beaches may be eroding, with Maui's shores in hot pursuit. It's not just hawaii's problem. Experts have estimated that 60% to 80% of the nation's shoreline is chronically
eroding, but Hawaii's economy is so dependent on healthy beaches that the loss of shoreline here is a much bigger deal.
A huge part of the problem is that Hawaiian homes and businesses were built right on the water. When walls or other shoreline structures are built, it prevents the beach from gaining sand from the land. Called "hardening the shoreline," these structures actually increase the rate of beach erosion because they prevent natural cycles of growth and retreat of beach sands. Naturally, higher waves are buffered by a shifting of sands from the beach and its dunes to further offshore, temporarily shortening the beach. But when a seawall is present, it doesn't allow for sand from the land to replenish the shifting beach, and it intensifies the strength of the waves, leading to erosion. Although the walls might initially protect property, they often result in beach loss and chronically eroded shores.But even without the coastal development, Hawaii's beaches would be crawling slowly inward in response to sea levels that have been rising since the 19th century. As climate change threatens even higher sea levels in the future, Hawaii's beaches are only going to get smaller.
The state is torn about what to do with its shrinking coastlines. Already, the state and hotels have spent over $3 million pumping in sand from offshore to preserve the width of Waikiki beach, a tourist hot spot. However, the cost to do so to all of Hawaii's beaches would be astronomical.
It's not just about the tourists, either. Hawaii's beaches are critical habitat for the highly endangered Hawaiian monk seal and other native flora and fauna, like the green sea turtle. And as more beaches are lost to the sea, more tourists will move into beaches that had been largely ignored by them, causing even more habitat loss and disturbance for these creatures. The beaches also act as natural buffers to prevent property damage from storm waves, and as these beaches narrow, waterfront areas become increasingly at risk to damage.
The state is considering a radical plan of buying up the waterfront land and demolishing the buildings there to allow the beach to retreat naturally. However, again, the cost of such an initiative will be high, especially with space at such a premium on the islands. Not many are going to be so eager to see their waterfront properties demolished.
Already, beaches like Lanikai and Ewa are likely too far gone to be saved, and they're lined with seawalls that just exacerbate the problem. Whatever the government is going to do, they'd better figure it out sooner rather than later. Hawaii's beaches are disappearing, and before we know it, there won't be much left to protect.
References
1. Charles H. Fletcher, Robert A. Mullane and Bruce M. Richmond (1997). Beach loss along armoured shorelines on Oahu, Hawaiian Islands. Journal of Coastal Research, v.13, no. 1, pp. 209-215.
2. State of Hawaii Financial Facts <http://hawaii.gov/dbedt/info/economic/library/facts/state>
