State Seal

 

DEPARTMENT OF LAND AND NATURAL RESOURCES

 

News Release

     LINDA LINGLE              

           GOVERNOR

_________________________________________________________________________________________________________

                                                                                                                                                                                               

                                                                                                                                              PETER T. YOUNG, CHAIRPERSON

                                                                                                                                              Phone: (808) 587-0401

                                                                                                                                              Fax: (808) 587-0390

                                                                                                                                             

_________________________________________________________________________________________________________

For Immediate Release: March 17, 2006

  

DLNR Activities

BLNR Holds Emergency Meeting

The Board of Land and Natural Resources (BLNR) held an emergency meeting March 16, 2006 to authorize the Department of the Attorney General and its agents, employees, consultants, and investigators to enter upon private property for the purposes of investigating and inspecting dams and reservoirs located within the County of Kauai pursuant to Hawaii Revised Statutes Chapter 179D.

The Board unanimously approved the emergency measure.

Hawaii Revised Statutes §92-8 (Cum. Supp. 2005) states that a board such as the Board of Land and Natural Resources (the board) may hold an emergency meeting in less time than usually required for notice under Haw. Rev. Stat. §92-7 (Cum. Supp. 2005) if the board finds that an imminent peril to the public health, safety, or welfare requires the meeting, or if an unanticipated event requires a board to take action within less time than provided by Haw. Rev. Stat. § 92-7 (Cum. Supp. 2005).

Dam Hazard Classifications

Federal Guidelines for Dam Safety
Hazard Potential Classification System for Dams
U.S. Department of Homeland Security
Federal Emergency Management Agency

Common practice among federal and state dam safety offices is to classify a dam according to the potential impact a dam failure (breach) or mis-operation (unscheduled release) would have on upstream and/or downstream areas or at locations remote from the dam.

Three classification levels are adopted as follows: Low, Significant and High, listed in order of increasing adverse incremental consequences. The classification levels build on each other, i.e., the higher order classification levels add to the list of consequences for the lower classification levels.

This hazard potential classification system categorizes dams based on the probable loss of human life and the impacts on economic, environmental, and lifeline interests. Improbable loss of life exists where persons are only temporarily in the potential inundation area.

For instance, this hazard potential classification system does not contemplate the improbable loss of life of the occasional recreational user of the river and downstream lands, passer-by, or non-overnight outdoor user of downstream lands. It should be understood that in any classification system, all possibilities cannot be defined. High usage areas of any type should be considered appropriately.

Judgment and common sense must ultimately be a part of any decision on classification. Further, no allowances for evacuation or other emergency actions by the population should be considered because emergency procedures should not be a substitute for appropriate design, construction, and maintenance of dam structures.

Dam hazard classifications refer to the potential loss of human life or property damage in the area downstream of the dam in event of failure or mis-operation of the dam or appurtenant facilities. It is not related to the present condition of the dam nor its stability.

Dams are classified with a hazard potential depending upon the downstream losses anticipated in event of failure. Hazard potential is not related to the structural integrity of a dam but strictly to the potential for adverse downstream effects if the dam were to fail.

High Hazard: Dams in the highest hazard potential category will be those located where failure will most likely result in the loss of life and cause serious damage to homes, extensive agricultural, industrial and commercial facilities, important public utilities, main highways, or railroads.

Significant Hazard: Significant potential category structures will be located in predominantly rural or agricultural areas where failure may result in the loss of life and damage isolated homes, secondary highways or minor railroads or cause interruption of use or service of relatively important public utilities.

Low Hazard: Dams conforming to criteria for the low hazard potential category generally will be located in rural or agricultural areas where failures may damage farm buildings, limited agricultural land, or township and county roads.

Conclusions of Task Force formed to recommend the Dam Hazard Potential system noted:

1. The proposed Hazard Potential Classification System for Dams provides a clear, simple, concise, and adaptable system to classify the hazard potential for dams.
2. The hazard potential rating does not reflect in any way on the current safety, structural integrity, or flood routing capability of the project water retaining structures.
3. The proposed classification system should be submitted to ICODS with a recommendation for peer review by ASDSO, USCOLD, ASCE, and the Canadian Dam Safety Association.
4. Future task groups should be established to consider design criteria associated with the various hazard classification systems.
5. The proposed Hazard Potential Classification System should be adopted in lieu of existing numerical and alphabetical systems. This is necessary to eliminate confusion in the dam safety community and to educate the public on the importance of dam safety.

Classifications of Dams in Hawaii

There are 133 dams in DLNR?s Hawaii Inventory of Dams. A majority of dams are on neighbor islands: Kauai has 53 (13 State-owned/40 privately-owned), Oahu has 16 (1 State-owned/15 privately-owned), Maui/Molokai/Lanai have 51 (1 State-owned/50 privately-owned), and Hawaii has 13 (4 State-owned/9 privately-owned).

There are 75 high risk dams in the State, 21 significant risk dams, 20 low risk dams and 17 dams with an undetermined risk.

Kauai (23-High, 8-Significant, 15-Low, 7-Undetermined)
Oahu (9-High, 5-Significant, 1-Low, 1-Undetermined)
Maui/Molokai/Lanai (36-High, 7-Significant, 3-Low, 3-Undetermined)
Hawaii (7-High, 1-Significant, 1-Low, 4-Undetermined)

DLNR Instructing Dam Owners to Inspect Dams and Provide Reports

DLNR is instructing all dam or reservoir owners to immediately inspect and report back to the Department the nature and condition of their dams or reservoirs. In addition to the inspection update, all recent maintenance records and documentation of operations and inspections are being requested.

DLNR is also instructing dam or reservoir owners to evaluate, and update if necessary, their emergency preparedness plans, including evaluation of potential downstream impacts should the dam or reservoir breach or partially breach.

Included in the letter are these types of requests:

· to update records of maintenance, operation and inspection activities on their dams and reservoirs;

· to update dam failure inundation maps, indicating downstream improvements that may be affected.

· to provide for the adequate and timely maintenance, operation, engineering and inspection of their dams and reservoirs and shall be responsible for any engineering and geologic investigations which may be required to insure public safety.

· to keep available and in good order records of original construction and any modifications, and shall report to the department their maintenance, operation and engineering activities, including piezometric data collection and geologic investigations.

· to advise the department of any sudden or unprecedented flood or unusual or alarming circumstance or occurrence existing or anticipated which may adversely affect the dam or reservoir.

Should an owner decide to remove a dam or reservoir, DLNR has offered to assist a property owner with the permit process and present the request to the BLNR or CWRM for action, as appropriate.

Recent Activities of DLNR Personnel

Engineering:

Four DLNR Engineers are on Kauai to inspect reservoirs and dams: The DLNR Dam Safety Section Head is consulting with Kauai County Public Works Engineers on addressing Ka Loko Reservoir; one DLNR Engineer is focusing inspections on Puu Ka Ele, Wailua, Upper Kapahi, Okinawa, Tanaka and Twin Reservoirs; another DLNR Engineer will be checking reservoirs on the south side of Kauai, including Elua and Waita Reservoirs; and another DLNR Engineer is stationed in the Kauai Civil Defense Operations Center.

DLNR Forestry Staff Monitoring continues:
· Upper Kapahi Reservoir, 96 million gallons maximum storage (State) (above Kapaa Town)
· Wailua Reservoir, 293 million gallons maximum storage (State) (above Wailua Homesteads)

DLNR has positioned a representative in the State Civil Defense operations center; in addition, Bob Masuda, DLNR Deputy Director, is positioned at the Kauai Civil Defense operations center. DLNR is working with the team of emergency response agencies in this effort.

State Parks Update:

Park camping permits have been suspended for the island of Kauai. Closure signs at the head end of the trail at Na Pali have been posted and the trail will remain closed as long as the severe weather persists. Polihale is closed and the road is impassible due to flooding. DLNR is also monitoring storm damage to the road to Kokee.

DLNR has closed the Fern Grotto due to damage to the landing dock. Weather permitting and pending assessments at the grotto, DLNR will attempt to have a portion of the landing dock rebuilt in the next few days so tours to the grotto can resume once the weather clears and the threat of flooding is diminished.

On Oahu, DLNR is working to remove two trees washed into the stream bed below Sacred Falls and conduct a clean up of the beach at Kahana.

Other DLNR Updates:

DLNR is engaged in debris clean up in the Ala Wai and is monitoring navigational hazards in State waters.

DLNR advises the public to stay off of Hawaii's trails and avoid swollen streams during the stormy conditions due to dangers from flash floods. People should not attempt to cross high, swift flowing water on roadways.


Assistance from US Geological Survey (USGS)

The USGS Pacific Islands Water Science Center will be working with DLNR and Hawaii State Civil Defense to assist with the following:

1. Installation of radio-equipped water-level gages on reservoirs where overtopping is a concern. They have ordered equipment from the mainland, which should arrive on Kauai today or Saturday. USGS is planning to work over the weekend so that they can install the equipment as soon as the decision is made one where the gages are to be located. The decision will be made at the local level on Kauai. USGS should be able to install up to 4 gages by the end of next week.

2. Monitoring of dam structural integrity using laser (LIDAR) equipment. The equipment and trained personnel from USGS?s California center should be on Kauai by early next week.
LIDAR is an acronym for LI ght D etection A nd Ranging. L IDAR is the technology of using pulses of laser light striking the surfaces of the earth and measuring the time of pulse return. LIDAR can measure distance, speed, rotation and chemical composition and concentration of a remote target where the target can be a clearly defined object. (In this case, it will measure any changes of a dam surface.)

3. Hydrologic and hydraulic assessment of the Ka Loko dam break flood:

· Document the distribution of rainfall in the area prior to and during the event.
· Document the runoff conditions in the area prior to and during the event.
· Document maximum water levels in Ka Loko Reservoir prior to failure and in the Morita Reservoir subsequent to the Ka Loko failure.
· Document the status of inflow and outflow to the Ka Loko Reservoir prior to the failure (inflow appears to be partly via the Kaloko Ditch).
· Compute the volume of water that was released from the Ka Loko Reservoir as a result of the failure.
· Compute peak discharge rates in Wailapa Stream between the Ka Loko and Morita Reservoirs and in Wailapa Stream downstream from Morita Reservoir.
· Document maximum water levels and areas of inundation associated with the flooding along Wailapa Stream.
· Determine amounts of scour and deposition of sediment along Wailapa Stream channel between Ka Loko Reservoir and the ocean

USGS headquarters has provided some funding from the national flood reserve to offset some costs of a hydrologic/hydraulic assessment and the local USGS office has some federal matching funds available. The State is expected to reimburse some of the USGS costs.

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For more information, media contact:
Clifford Inn
DLNR Education and Outreach Coordinator
Phone: (808) 587-0407