159 palama, kauai, hawaiipalama, kauai, hawaii the palama study area extends from koheo point in the...

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423010001 422001001 423010002 423010010 423010004 159 o 33' W 159 o 33'30" W 40" 20" 10" 40" 50" 159 o 31'20" W 30" 159 o 32' W 20" 30" 10" 50" 21 o 52'50" N 30" 20" 10" 21 o 53'40" N 21 o 53' N 21 o 52'50" N 30" 20" 10" 21 o 53'40" N 21 o 53' N 159 o 33' W 159 o 33'30" W 40" 10" 40" 50" 159 o 31'20" W 30" 159 o 32' W 20" 30" 10" 50" 20" Palama, Kauai, Hawaii The Palama study area extends from Koheo Point in the west to Palama Beach in the east. The area is comprised of basalt rock bluffs and headlands with boulders, cobble, and sand dominating the shoreline. The coastline is exposed to swell from the south during the summer months. The two sandy beaches within this study area are located at the eastern end, to the south and east of Nomilu Fishpond. The average shoreline change at the beach at Makaokahai Point (transects 98 – 100) is experiencing slight erosion at an average rate of -0.2 ft/yr. Palama Beach (transects 102 - 121) also exhibits erosion with an average shoreline change rate of -0.5 ft/yr. Previous studies 1 do not include the Palama region in their analysis. 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. AREA DESCRIPTION HISTORICAL SHORELINES Jan 1928 Apr 1975 Oct 1981 Jul 1987 Mar 1988 Nov 2006 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. 400 300 200 1200 900 600 100 300 0 0 100 300 Scale 1:3000 Meters Feet Latitude/Longitude coordinates UTM coordinates 159 o 33'30" W 2415700mN N 0 0 10km 10mi Kauai Palama 446100mE 442300mE 37 38 39 40 41 42 43 50 24 35 34 33 32 31 25 30 36 29 28 26 27 44 45 47 48 49 51 52 53 54 60 46 58 57 56 55 59 446100mE 442300mE 37 38 39 40 41 42 43 50 24 35 34 33 32 31 25 30 36 29 28 26 27 44 45 47 48 49 51 52 53 54 60 46 58 57 56 55 59 12 11 10 09 08 07 06 05 04 02 03 01 24200 99 2419600mN 2421300mN 97 98 12 11 10 09 08 07 06 05 04 02 03 01 24200 99 2419600mN 2421300mN 97 98 100 102 105 110 115 120 121 98 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. Shoreline Change Rate (ft/yr) -1 0 1 -1 0 1 98 100 Shoreline Change Rate (ft/yr) -1 0 1 -1 0 1 102 105 110 115 120121 Contract C25514 Contract 7249 Charles Fletcher, Matthew Barbee, Siang-Chyn Lim, Matt Dyer 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. Nomilu Fishpond Palama Beach Makaokahai Pt. Nahunakueu Koheo Point

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Page 1: 159 Palama, Kauai, HawaiiPalama, Kauai, Hawaii The Palama study area extends from Koheo Point in the west to Palama Beach in the east. The area is comprised of basalt rock bluffs and

423010001

422001001

423010002

423010010

423010004

422001010

159o33' W159o33'30" W 40"20" 10" 40"50" 159o31'20" W30" 159o32' W20" 30"10" 50"

21o 52

'50"

N30

"20

"10

"21

o 53'4

0" N

21o 53

' N

21o52'50" N

30"20"

10"21

o53'40" N21

o53' N

159o33' W159o33'30" W 40"10" 40"50" 159o31'20" W30" 159o32' W20" 30"10" 50"20"

Palama, Kauai, HawaiiThe Palama study area extends from Koheo Point in the west to Palama Beach in the east. The area is comprised of basalt rock bluffs and headlands with boulders, cobble, and sand dominating the shoreline. The coastline is exposed to swell from the south during the summer months. The two sandy beaches within this study area are located at the eastern end, to the south and east of Nomilu Fishpond.

The average shoreline change at the beach at Makaokahai Point (transects 98 – 100) is experiencing slight erosion at an average rate of -0.2 ft/yr. Palama Beach (transects 102 - 121) also exhibits erosion with an average shoreline change rate of -0.5 ft/yr. Previous studies1 do not include the Palama region in their analysis.

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.

AREA DESCRIPTION HISTORICAL SHORELINES

Jan 1928Apr 1975Oct 1981Jul 1987Mar

1988Nov

2006

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.

400 300200

1200 900600

100

3000

0100

300

Scale 1:3000Meters

FeetLatitude/Longitude coordinatesUTM coordinates

159o33'30" W2415700mN

N 0

0 10km

10mi

Kauai

Palama

446100mE442300mE 37 38 39 40 41 42 43 5024 353433323125 30 36292826 27 44 45 47 48 49 51 52 53 54 6046 58575655 59

446100mE442300mE 37 38 39 40 41 42 43 5024 353433323125 30 36292826 27 44 45 47 48 49 51 52 53 54 6046 58575655 59

1211

1009

0807

0605

0402

0301

2420099

2419600m

N24213

00mN

9798

1211

1009

0807

0605

0402

0301

2420

099

2419

600m

N24

2130

0mN

9798

100

102

105

110

115

120 12

1

98

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.

ShorelineChange Rate (ft/yr)

-1

0

1

-1

0

1

98 100

Shoreline Change Rate (ft/yr)

-1

0

1

-1

0

1

102105

110

115

120121

Contract C25514 Contract 7249

Charles Fletcher, Matthew Barbee, Siang-Chyn Lim,Matt Dyer 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.

NomiluFishpond

Palama Beach

Makaokahai Pt.

Nahunakueu

Koheo Point