1
459001003 459001021 458002002 459001024 459008001 459003035 459003040 459005019 459003044 459003036 459003009 459005001 459002035 459003001 459006005 459006006 459002036 459005013 459002051 459006001 459005017 459003034 459006004 459005028 459002052 459006003 459005005 459003041 459003031 459005018 459003039 459002032 459003029 459002048 459002072 459002055 459003008 459006002 459003038 459003033 459003030 459002057 459002046 459003042 459002033 459003005 459005020 459002034 459003048 459006009 459002050 459003007 459003003 459003045 459006011 459005004 459003002 459006012 459002031 459005014 459006010 459002047 459002063 459002070 459001025 459003004 459003046 459002066 459005029 459005008 459005022 459002067 459003047 459005026 459005021 459002039 459002071 459005027 459005023 459005012 Haena, Kauai, Hawaii 0 0 10km 10mi Kauai Haena Latitude/Longitude coordinates UTM coordinates 159 o 47'20" W 2431400mN N 85 84 83 2458600mN 2456500mN 66 67 68 69 70 82 71 72 73 74 75 76 77 78 79 80 81 96 97 98 99 4400 01 02 03 04 05 06 07 08 09 10 11 12 13 14 16 15 17 18 19 439500mE 20 21 22 23 442400mE 96 97 98 99 4400 01 02 03 04 05 06 07 08 09 10 11 12 13 14 16 15 17 18 19 439500mE 20 21 22 23 442400mE 66 67 68 69 70 71 72 73 74 2458600mN 75 76 77 78 79 80 81 82 83 84 85 2456500mN 50" 40" 30" 10" 20" 159 o 34' W 159 o 33'40" W 50" 159 o 35'10" W 159 o 35' W 50" 40" 30" 10" 20" 159 o 34' W 40" 50" 159 o 35'10" W 159 o 35' W 10" 22 o 13' N 20" 22 o 12'50'' N 30" 40" 22 o 13'50'' N 10" 22 o 13' N 20" 22 o 12'50'' N 30" 40" 22 o 13'50'' N 159 o 33'40" W 400 300 200 1200 900 600 100 300 0 0 100 300 Scale 1:3000 Meters Feet Contract C25514 Contract 7249 Charles Fletcher, Matthew Barbee, Siang-Chyn Lim, Matt Dyer, Craig Senter and Ayesha Genz University of Hawaii Coastal Geology Group School of Ocean and Earth Sciences and Technology 1680 East West Road, Honolulu, HI 96822, U.S.A. The preparation of this poster was financed in part by the Coastal Zone Management Act of 1972, as amended, administered by the Office of Ocean and Coastal Resource Man- agement, National Ocean Service, National Oceanic and Atmospheric Administration, United States Department of Commerce, through the Office of Planning, State of Hawaii. Kuhio Highway Kuhio Hi ghway Kuhio High way Kailio Point Haena Point Haena Beach Park Haena State Park AREA DESCRIPTION HISTORICAL SHORELINES Erosion rate measurement locations (shore-normal transects) Historical beach positions, color coded by year, are determined using orthorectified and georefer- enced aerial photographs and National Ocean Survey (NOS) topographic survey charts. The low water mark is used as the historical shore- line, or shoreline change reference feature (SCRF). Movement of the SCRF along shore-normal transects (spaced every 66 ft) is used to calcu- late erosion rates. T-sheet 1927 Feb 2002 Nov 1950 Oct Apr Jul Nov 1963 1975 1987 1995 1988 Mar Jan 2008 Erosion Rate Accretion Rate SHORELINE CHANGE RATES Historical shoreline positions are measured every 66 ft along the shoreline. These sites are denoted by yellow shore-perpendicular transects. Changes in the position of the shorelines through time are used to calculate shoreline change rates (ft/yr) at each transect location. Annual shoreline change rates are shown on the shore-parallel graph. Red bars on the graph indicate a trend of beach erosion, while blue bars indicate a trend of accretion. Approximately every fifth transect and bar of the graph is numbered. Where necessary, transects have been purposely deleted to maintain consistent alongshore spacing. As a result transect numbering is not consecutive everywhere. The rates are smoothed alongshore using a 1-3-5-3-1 technique to normalize rate differences on adjacent transects. The Haena study area (transects 0 – 156) is located on the north shore of Kauai. The area is bounded by the steep ridges of the Na Pali coast to the west and Haena Point to the east. The shoreline is composed of carbonate sand, exposed beach rock, and basalt boulders deposited by the several streams that interrupt the beach. An extensive fringing reef lies offshore resulting in varying wave approach directions at the shoreline 1 . The coast in this area is exposed to large seasonal swell during the winter months. Overall, the Haena study area is experiencing erosion at an average rate of -1.0 ft/yr. The study area is divided into three areas. Haena Beach Park is located in the eastern portion of the area (transects 101 – 156) and is eroding at an average rate of -1.3 ft/yr. The central portion of the area (transects 18 – 100) is eroding at an average rate of -1.0 ft/yr. The western portion of the area (transects 0 – 17), which covers Haena State Park and Kee Beach, is eroding at an average rate of -0.5 ft/yr. Study results generally agree with Sea Engineering (1992) 1 for this portion of coast except at Haena State Park where the vegetation line is difficult to identify with accuracy on the selected photography. 1 Makai Ocean Engineering and Sea Engineering, 1991 Aerial Photograph Analysis of Coastal Erosion on the Islands of Kauai, Molokai, Lanai, Maui, and Hawaii. State of Hawaii Office of Coastal Zone Management Program. -2 -1 0 -2 -1 0 0 5 10 15 17 Shoreline Change Rate (ft/yr) -2 -1 0 -2 -1 0 Shoreline Change Rate (ft/yr) 25 40 45 50 30 35 55 60 65 70 75 80 85 90 95 100 18 20 -2 -1 0 -2 -1 0 Shoreline Change Rate (ft/yr) 110 120 125 130 135 140 145 150 155 115 156 101 105 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 156 155 150 145 140 135 130 125

Haena, Kauai, Hawaii - SOEST | School of Ocean and Earth Science

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Page 1: Haena, Kauai, Hawaii - SOEST | School of Ocean and Earth Science

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Haena, Kauai, Hawaii

0

0 10km

10mi

KauaiHaena

Latitude/Longitude coordinatesUTM coordinates

159o47'20" W2431400mN

N

8584

8324586

00mN

2456500m

N66

6768

6970

8271

7273

7475

7677

7879

8081

96 97 98 99 4400 01 02 03 04 05 06 07 08 09 10 11 12 13 14 1615 17 18 19439500mE 20 21 22 23 442400mE

96 97 98 99 4400 01 02 03 04 05 06 07 08 09 10 11 12 13 14 1615 17 18 19439500mE 20 21 22 23 442400mE66

6768

6970

7172

7374

2458

600m

N75

7677

7879

8081

8283

8485

2456

500m

N

50"40" 30" 10"20" 159o34' W 159o33'40" W50" 159o35'10" W 159o35' W

50"40" 30" 10"20" 159o34' W 40"50" 159o35'10" W 159o35' W

10"

22o 13

' N20

"22

o 12'5

0'' N

30"

40"

22o 13

'50'

' N10"

22o13' N

20"22

o12'50'' N30"

40"22

o13'50'' N

159o33'40" W

400 300200

1200 900600

100

3000

0100

300

Scale 1:3000Meters

Feet

Contract C25514 Contract 7249

Charles Fletcher, Matthew Barbee, Siang-Chyn Lim,Matt Dyer, Craig Senter and Ayesha GenzUniversity of Hawaii Coastal Geology GroupSchool of Ocean and Earth Sciences and Technology1680 East West Road, Honolulu, HI 96822, U.S.A.

The preparation of this poster was financed in part by the Coastal Zone Management Act of 1972, as amended, administered by the Office of Ocean and Coastal Resource Man-agement, National Ocean Service, National Oceanic and Atmospheric Administration, United States Department of Commerce, through the Office of Planning, State of Hawaii.

Kuhio Highway

Kuhio Highway

Kuhio Highway

KailioPoint

HaenaPoint

HaenaBeach Park

HaenaState Park

AREA DESCRIPTION

HISTORICAL SHORELINES

Erosion rate measurement locations(shore-normal transects)

Historical beach positions, color coded by year, are determined using orthorectified and georefer-enced aerial photographs and National Ocean Survey (NOS) topographic survey charts. The low water mark is used as the historical shore-line, or shoreline change reference feature (SCRF).

Movement of the SCRF along shore-normal transects (spaced every 66 ft) is used to calcu-late erosion rates.

T-sheet 1927

Feb 2002

Nov 1950OctAprJul

Nov

196319751987

19951988Mar

Jan 2008

Erosion RateAccretion Rate

SHORELINE CHANGE RATES

Historical shoreline positions are measured every 66 ft along the shoreline. These sites are denoted by yellow shore-perpendicular transects. Changes in the position of the shorelines through time are used to calculate shoreline change rates (ft/yr) at each transect location.

Annual shoreline change rates are shown on the shore-parallel graph. Red bars on the graph indicate a trend of beach erosion, while blue bars indicate a trend of accretion. Approximately every fifth transect and bar of the graph is numbered. Where necessary, transects have been purposely deleted to maintain consistent alongshore spacing. As a result transect numbering is not consecutive everywhere. The rates are smoothed alongshore using a 1-3-5-3-1 technique to normalize rate differences on adjacent transects.

The Haena study area (transects 0 – 156) is located on the north shore of Kauai. The area is bounded by the steep ridges of the Na Pali coast to the west and Haena Point to the east. The shoreline is composed of carbonate sand, exposed beach rock, and basalt boulders deposited by the several streams that interrupt the beach. An extensive fringing reef lies offshore resulting in varying wave approach directions at the shoreline1. The coast in this area is exposed to large seasonal swell during the winter months.

Overall, the Haena study area is experiencing erosion at an average rate of -1.0 ft/yr. The study area is divided into three areas. Haena Beach Park is located in the eastern portion of the area (transects 101 – 156) and is eroding at an average rate of -1.3 ft/yr. The central portion of the area (transects 18 – 100) is eroding at an average rate of -1.0 ft/yr. The western portion of the area (transects 0 – 17), which covers Haena State Park and Kee Beach, is eroding at an average rate of -0.5 ft/yr.

Study results generally agree with Sea Engineering (1992) 1 for this portion of coast except at Haena State Park where the vegetation line is difficult to identify with accuracy on the selected photography.

1 Makai Ocean Engineering and Sea Engineering, 1991 Aerial Photograph Analysis of Coastal Erosion on the Islands of Kauai, Molokai, Lanai, Maui, and Hawaii. State of Hawaii Office of Coastal Zone Management Program.

-2

-1

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-2

-1

0

0

5

10

1517

Shor

elin

e Ch

ange

Rat

e (ft

/yr)

-2

-1

0

-2

-1

0

Shoreline Change Rate (ft/yr)25 40 45 5030 35 55 60 65 70 75 80 85 90 95 10018 20

-2-1

0

-2-1

0

Shoreline Change Rate (ft

/yr)

110

120

125

130

135

140

145

150

155

115

156

101

105

0

5

10

15

20

25

30

35

40

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100

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125