Researchers to probe beach restoration options in Kahana
KAHANA – Funding has been released by the county for a study on a much-needed facelift at Kahana Beach.
Driven by two local authorities, Jim Buika and Tara Owens, a Request for Proposals (RFP) was issued for a “Scoping Study for Kahana Beach Erosion Mitigation through Regional Beach Nourishment.”
Read the full article in Lahaina News website:
Coral Reef Ecosystems, Water Quality, and Upland Activities
The health of beaches is closely tied to the health of the coral reef ecosystem, which is itself closely tied to upland land practices. Hence, effective beach management requires a geographically broader approach
known as integrated coastal zone management. Although this report has focused mainly on the shoreline area-the beach, the dunes, and the coastal plain-we have included some recommendations for more effective protection of the coral reef ecosystem and better management of upland land practices.In many cases, improper control of runoff at agricultural lands and construction sites, even those far from the coast, has degraded the water quality of coastal areas. For example, recent construction without adequate erosion control measures for the Maui Ocean Center has led to frequent silt plumes in Ma’alaea Bay and negative impacts on the coral reef. Silt diminishes light penetration and eventually settles out on
the seafloor. This harms coral and other marine organisms (e.g.,
foraminifera, an important component of beach sand) and limits safe and enjoyable ocean recreation. Runoff also transports nutrients, pesticides,
and other pollutants to coastal waters compounding the impacts on water quality. [excerpt from the “Beach Management Plan for Maui”]
Beach Restoration and Nourishment Activities
Shoreline protection, conservation, and restoration projects are a major objective of the County’s Coastal Zone Management Program.
The Planning Department works closely with the Hawaii Office of Coastal & Conservation Lands to facilitate long-term solutions to coastal erosion and coastal hazards.
Sea Grant Program
Technical assistance provided through the University of Hawaii’s Sea Grant Program and financial assistance provided by the Hawaii State Coastal Zone
Management Program support a wide range of management options for shoreline protection. Site visits, regularly scheduled communication, and networking with other coastal practitioners assists Maui County in using recent research results and technologies to improve coastal protection and shoreline conservation.
Visit the Maui County website for the full story:
300,000 cubic yards of sand have been discovered off Kahana Bay in April, and the offshore sand is intended to be dredged to re-nourish eroding beaches in west Maui.
“It’s a long process to get the sand to shore, said Tara Owns, coastal processes and hazards specialist for the University of Hawaii Sea Grant. Research, planning and permitting could take five years with costs estimated between $15 million and $20 million…”
Read Full Article, Hawaii Tribune Herald
Study to deter Maui beach erosion finds offshore sand
Beach nourishment—also referred to as beach renourishment, beach replenishment or sand replenishment—describes a process by which sediment (usually sand) lost through longshore drift or erosion is replaced from sources outside of the eroding beach. A wider beach can reduce storm damage to coastal structures by dissipating energy across the surf zone, protecting upland structures and infrastructure from storm surges, tsunamis and unusually high tides. Beach nourishment is typically part of a larger coastal defense scheme. Nourishment is typically a repetitive process, since it does not remove the physical forces that cause erosion, but simply mitigates their effects.
The first nourishment project in the U.S. was at Coney Island, New York in 1922–23 and is now a common shore protection measure utilized by public and private entities.
‘Beach-quality sand’ discovered as erosion reaches ‘crisis’ level
KAHANA BAY – Maui County shoreline planners are “elated” after discovering more than 300,000 cubic yards of “beach-quality sand” off Kahana Bay, which could replenish the beachfronts of numerous condominiums that have been slowly disappearing into the ocean.
However, the discovery may be too little, too late.
Condo and resort owners have spent hundreds of thousands of dollars constructing barriers and making repairs to protect their properties from the ocean over the past few years, and coastal experts say this winter was “the worst” so far. El Nino-generated high tides and strong swells eroded the West Maui coastline and destroyed pool decks, stairs, walkways and small structures.
Hawaii’s Coastal Erosion Predicted To Double By 2050, New Study Says
If you think there’s not much beach space left in Waikiki right now, chances are it’s going to be a lot worse in 35 years.
Scientists at the University of Hawaii’s School of Ocean and Earth Sciences and Technology (SOEST) studied data from 10 retreating beaches on Oahu, Maui and Kauai islands and found that beaches will erode as much as 20 feet by 2050 and 40 feet by 2100.
The study, titled “Doubling Of Coastal Erosion Under Rising Sea Level By Mid-Century In Hawaii,” was published this week in the journal “Natural Hazards.”
Hawaii Coastal Erosion
The Hawaii Shoreline Study provides shoreline change data to the public and government partners to assist in decision-making in the coastal zone. Shorelines are highly variable environments characterized by a number of natural hazards. These include: tsunami, storm surge, high winds, coastal erosion, sea-level rise, and high wave overtopping. Building on eroding coasts increases vulnerability to all these hazards. A direct step to mitigating the impact of coastal hazards is to exercise avoidance (Hwang, 2005) by mapping high hazard zones designed, in part, on data such as found in this study.