Keawakapu Reef Remediation Options Considered

Courtesy Image.

By Wendy Osher

The Department of Land and Natural Resources will hold a public information meeting this week to present a technical report and corrective action plan for the Keawakapu artificial reef in South Maui.

The purpose of the plan is to remediate coral accidentally damaged when concrete modules were placed at the Keawakapu artificial reef in early December, 2009.

The meeting will run from 6 to 8 p.m. on Thursday, January 10, 2013, at the Hawaiian Islands Humpback Whale National Marine Sanctuary education center, located at 726 South Kihei Road.

The technical report, prepared for DLNR’s Division of Aquatic Resources, provides three remediation options that include: 1) leaving all modules in place; 2) partial removal of some modules to minimize further coral damage; and 3) removal of all 125 modules that landed on live coral.

Based on the technical report recommendations, officials with the DAR propose to remove all of the 125 modules that are on the reef.

DAR staff, along with staff from Planning Solutions, Inc., will explain the scope of the 110-page technical report and the options under consideration.

The full report is available for viewing at the following direct LINK.

Incident Report:

Dec. 2, 2009:  Approximately 1,400 “Z”-shaped concrete fish habitats were deployed at the Keawakapu Artificial Reef, offshore of Keawakapu, Maui.

Subsequently, DLNR staff surveyed the placement of the Z blocks. The majority of the Z blocks, about 1,200, were located within the designated artificial reef boundaries. However, approximately 125 Z blocks fell on live coral outside the artificial reef boundaries. DLNR conducted an internal investigation and invited National Oceanic and Atmospheric Administration and US Fish and Wildlife Service to conduct an independent investigation to develop new standard operating procedures so this kind of incident does not occur in the future.

March 2010: DLNR held a public information meeting on Maui to present the findings and recommendations of the investigation by NOAA and USFWS. At that meeting the public provided additional information about what should be done. The preferred option was total removal of all modules outside the designated area.

DLNR provided the NOAA and USFWS investigation to Planning Solutions, Inc. to analyze the data and develop an environmental assessment to determine the most appropriate remedial strategy. DLNR submitted an application to the US Army Corps of Engineers to reduce the boundaries of the artificial reef site from approximately 52 acres to approximately 37 acres. If accepted, this revision will mean that all Z blocks deployed in December 2009 are within the designated artificial reef site. All re-deployed modules will be located in the revised smaller site.

Background:

In 1962, the State created the Keawakapu Artificial Reef. It is approximately 52 acres and consists of 150 cars, 2,250 tire modules, 35 concrete slabs, and 1 vessel–“St. Anthony”–that was added in 1997. The 1,400 concrete modules was the first deployment since 1990.

DLNR has four shallow water (50-100 foot) artificial reefs and one deepwater (300-420 foot) artificial reef. Three of the shallow water reefs are located off O‘ahu at Wai‘anae, in Maunalua Bay, and Kualoa. The fourth is located off Keawakapu on Maui. The deep water artificial reef is located off ‘Ewa Beach, O‘ahu.

State officials point to studies which they say have shown that artificial reefs are effective in enhancing reef habitat, increasing fish biomass, and diversifying the species of fish within the reef site.

Artificial reefs are also identified as a key component in the State fishery enhancement programs as well as a substrate for the settlement of coral polyps, and serve as SCUBA and snorkel dive sites.

***Supporting information courtesy State of Hawai’i, Department of Land and Natural Resources.