Waialua; Master Drainage Plan

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

HOUSE OF REPRESENTATIVES                H.B. NO.           
TWENTIETH LEGISLATURE, 2000                                     
STATE OF HAWAII                                                 

                   A  BILL  FOR  AN  ACT



 1      SECTION 1.  (a)  Development has resulted in the
 2 urbanization of lowlands, stream valley areas, and flat coastal
 3 areas.  In the course of this process, man has progressively
 4 encroached on the flood plains in the low inland areas and the
 5 coast areas, where urged by the desire to protect his life and
 6 property, man has found it necessary to resort to structural or
 7 non-structural measures, or both, such as the constructions of
 8 levees along the rivers, and land use management. 
 9      Flooding is the primary natural hazard that has inflicted
10 extensive damage in the State of Hawaii.   Floods in Hawaii can
11 be classified into two categories, according to their origins:
12 flash floods caused by heavy rainfall and oceanic floods caused
13 by tsunamis, high seas, and high surf.  Flash floods can also
14 occur concurrently with strong winds during a hurricane.
15      (b)  The Waialua-Haleiwa flood plain is located on the
16 northwestern coast of Oahu and has an approximate area of two
17 square miles.  The watershed above the Waialua-Haleiwa flood
18 plain is the largest on Oahu, containing an area of 96.5 square
19 miles.  On December 2, 1999, a storm occurred in the Koolaus

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 1 which caused water to spill over the emergency spillway at
 2 Wahiawa Reservoir into Kaukonahua Stream and caused flood waters
 3 to rise up to the floorboards of resident's homes at Otake Camp.
 4      (c)  The primary purpose of the Waialua-Haleiwa stormwater
 5 drainage master plan is to provide residents of Waialua and the
 6 city and county of Honolulu with specific engineering
 7 recommendations for the control of storm drainage throughout the
 8 study area, to reduce repetitive flooding to residents and
 9 businesses in the area, and to reduce the constant drain on city,
10 state, and federal resources whenever a flood occurs.
11      Other important goals to be accomplished are complying with
12 new federal and state requirements for reducing pollution
13 associated with the city and county's storm drainage system, and
14 protecting natural resource areas that are or may be affected by
15 stormwater drainage.
16      Specific objectives of the plan are to:
17      (1)  Identify the major drainage basins and provide a
18           delineation of the basin boundaries and the major
19           drainage system;
20     (2)  Identify the hydraulic capacities and associated levels
21          of protection afforded by the existing major drainage
22          systems;
23     (3)  Identify the houses that are or are not covered by flood

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                                     H.B. NO.           

 1          insurance that are repeatedly flooded;
 2     (4)  Look at various ways to elevate, relocate, retrofit, and
 3          floodproof those insurable houses;
 4     (5)  Identify needs and opportunities to reduce stormwater
 5          pollution loading, and to protect or enhance natural
 6          resource areas that are, or may be, affected by
 7          stormwater drainage;
 8     (6)  Identify the capital improvement projects that will
 9          solve or reduce existing drainage problems and provide
10          acceptable flood protection for the study area under
11          ultimate planned development conditions; and
12     (7)  Identify the criteria to plan, design, maintain, and
13          monitor storm drainage facilities.
14     (d)  The scope of the master plan will include the following:
15     (1)  Initial problem identification report;
16     (2)  System evaluation report; and
17     (3)  Implementation of the master plan.
18     (e)  The organization of the master plan will include:
19     (1)  A description of the study area;
20     (2)  Evaluation of known drainage, water quality, and natural
21          resource related problems and issues; 
22     (3)  Improvement alternatives and processes used to rank
23          projects;

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                                     H.B. NO.           

 1     (4)  Development of project cost estimates and overview of
 2          the capital improvement plan;
 3     (5)  Design standards for flood control and water quality
 4          projects;
 5     (6)  Recommendations for operation and maintenance of storm
 6          drainage facilities; and
 7     (7)  Conceptual design for monitoring water quality and flows
 8          to assist the county in meeting the storm water
 9          management goals.
10     The Waialua-Haleiwa stormwater drainage master plan will
11 benefit the city, State, and Federal Emergency Management Agency
12 by identifying the houses that are repeatedly damaged by floods
13 and methods will be utilized to get them out of harm's way.  This
14 will reduce the cost incurred by residents due to the floods,
15 reduce strain to the city and state government's resources in
16 responding to floods, and will cause less disruption to
17 residents.
18     SECTION 2.  There is appropriated out of the general revenues
19 of the State of Hawaii the sum of $500,000, or so much thereof as
20 may be necessary for fiscal year 2000-2001, for the formation of
21 a Waialua-Haleiwa stormwater drainage master plan.
22     SECTION 3.  The sum appropriated shall be expended by the
23 department of land and natural resources for the purposes of this
24 Act.

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                                     H.B. NO.           

 1     SECTION 4.  This Act shall take effect on July 1, 2000.
 3                           INTRODUCED BY:  _______________________