Report Title:

Appropriation; Waialua-Haleiwa; Master Drainage Plan

 

Description:

Appropriates $500,000 for drafting a Waialua-Haleiwa stormwater drainage master plan.

 

THE SENATE

S.B. NO.

1387

TWENTY-FIRST LEGISLATURE, 2001

 

STATE OF HAWAII

 


 

A BILL FOR AN ACT

 

making an appropriation for a waialua-haleiwa stormwater drainage master plan.

 

BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF HAWAII:

SECTION 1. (a) Development has resulted in the urbanization of lowlands, stream valley areas, and flat coastal areas. In the course of this process, humanity has progressively encroached on the flood plains in the low inland areas and the coastal areas. Where urged by the desire to protect life and property, humanity has found it necessary to resort to structural or non-structural measures, or both, such as the constructions of levees along the rivers, and land use management.

Flooding is the primary natural hazard that has inflicted extensive damage in the State of Hawaii. Floods in Hawaii can be classified into two categories, according to their origins: flash floods caused by heavy rainfall and oceanic floods caused by tsunamis, high seas, and high surf. Flash floods can also occur concurrently with strong winds during a hurricane.

(b) The Waialua-Haleiwa flood plain is located on the northwestern coast of Oahu and is approximately two square miles. The watershed above the Waialua-Haleiwa flood plain is the largest on Oahu, containing an area of 96.5 square miles. On December 2, 1999, a storm occurred in the Koolaus which caused water to spill over the emergency spillway at Wahiawa Reservoir into Kaukonahua Stream and caused flood waters to rise up to the floorboards of resident's homes at Otake Camp.

(c) The primary purpose of the Waialua-Haleiwa stormwater drainage master plan is to provide residents of Waialua and the city and county of Honolulu with specific engineering recommendations for the control of storm drainage throughout the study area, to reduce repetitive flooding to residents and businesses in the area, and to reduce the constant drain on city, state, and federal resources whenever a flood occurs.

Other important goals to be accomplished are complying with new federal and state requirements for reducing pollution associated with the city and county's storm drainage system, and protecting natural resource areas that are, or may be affected by, stormwater drainage.

Specific objectives of the plan are to:

(1) Identify the major drainage basins and provide a delineation of the basin boundaries and the major drainage system;

(2) Identify the hydraulic capacities and associated levels of protection afforded by the existing major drainage systems;

(3) Identify the houses that are or are not covered by flood insurance that are repeatedly flooded;

(4) Look at various ways to elevate, relocate, retrofit, and floodproof those insurable houses;

(5) Identify needs and opportunities to reduce stormwater pollution loading, and to protect or enhance natural resource areas that are, or may be, affected by stormwater drainage;

(6) Identify the capital improvement projects that will solve or reduce existing drainage problems and provide acceptable flood protection for the study area under ultimate planned development conditions; and

(7) Identify the criteria to plan, design, maintain, and monitor storm drainage facilities.

(d) The scope of the master plan shall include the following:

(1) Initial problem identification report;

(2) System evaluation report; and

(3) Implementation of the master plan.

(e) The organization of the master plan shall include:

(1) A description of the study area;

(2) Evaluation of known drainage, water quality, and natural resource related problems and issues;

(3) Improvement alternatives and processes used to rank projects;

(4) Development of project cost estimates and overview of the capital improvement plan;

(5) Design standards for flood control and water quality projects;

(6) Recommendations for operation and maintenance of storm drainage facilities; and

(7) Conceptual design for monitoring water quality and flows to assist the county in meeting the stormwater management goals.

The Waialua-Haleiwa stormwater drainage master plan will benefit the city, state, and Federal Emergency Management Agency by identifying the houses that are repeatedly damaged by floods, and methods will be utilized to get them out of harm's way. This will reduce the cost incurred by residents due to the floods, reduce strain to the city and state government's resources in responding to floods, and will cause less disruption to residents.

SECTION 2. There is appropriated out of the general revenues of the State of Hawaii the sum of $500,000, or so much thereof as may be necessary for fiscal year 2001-2002, for the formation of a Waialua-Haleiwa stormwater drainage master plan.

SECTION 3. The sum appropriated shall be expended by the department of land and natural resources for the purposes of this Act.

SECTION 4. This Act shall take effect on July 1, 2001.

INTRODUCED BY:

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