Laura Island, which is located about 50 km away from
downtown, is a source of water supply in Majuro atoll, which is the
capital of the Republic of the Marshall Islands. Low and flat Majuro
atoll has neither river nor lake. It is very important for Majuro atoll to
ensure the conservation of its water resources. However, upconing,
which is the process of partial rising of the freshwater-saltwater
boundary near the water-supply well, was caused by the excess
pumping from it during the severe drought in 1998. Upconing will
make the water usage of the freshwater lens difficult. Thus,
appropriate water usage is required to prevent up coning in the
freshwater lens because there is no other water source during drought. Numerical simulation of water usage applying SEAWAT model
was conducted at the central part of Laura Island, including the water
supply well, which was affected by upconing. The freshwater lens was
created as a result of infiltration of consistent average rainfall. The lens
shape was almost the same as the one in 1985. 0 of monthly rainfall
and variable daily pump discharge were used to calculate the
sustainable pump discharge from the water supply well. Consequently,
the total amount of pump discharge was increased as the daily pump
discharge was increased, indicating that it needs more time to recover
from upconing. Thus, a pump standard to reduce the pump intensity is
being proposed, which is based on numerical simulation concerning
the occurrence of the up-coning phenomenon in Laura Island during
the drought.
[1] A. C. Falkland, “Hydrology and Water Management on Small Tropical
Islands, Hydrology of Warm Humid Regions (Proceedings of the
Yokohama Symposium),” IAHS Publication No.216, 1993, pp.263-303.
[2] S. S. Anthony, and L.F.Peterson, et. al., “Geohydrology of the Laura
Freshwater Lens, Majuro Atoll: A Hydro-geochemical Approach,” GSA
Bulletin, Vol.101, No.8, 1989, pp.1066-1075.
[3] S. S. Anthony, “Techniques for Appraisal of Groundwater Resources on
Atoll Islands: Case Studies from Micronesia,” Tropical Hydrology and
Caribbean Water Resources American Water Resources Association,
1990, pp.291-300.
[4] W. Guo, and D. L.Christian, “User’s Guide to SEAWAT: A Computer
Program for Simulation of Three-Dimensional Variable-Density
Ground-Water Flow,” USGS Techniques of Water-Resources
Investigations 6-A7, 2002, pp.7-18.
[5] K. Koda, and T. Kobayashi, et al., “Estimation of Hydraulic Parameters of
Laura Lens Aquifer (Japanese),” Journal of the JSIDRE, Vol.81, No.7,
2013, pp.541-545.
[6] K. Koda, and T. Kobayashi, et al., “Situation of the Freshwater Lens in
Laura Islands, Majuro Atoll, the Republic of the Marshall Islands
(Japanese),” Journal of the Japanese Geothechnical Society, Vol.62,
No.682/683, 2014, pp.30-33.
[7] K. T. Presley, “Effect of the 1998 Drought on the Freshwater Lens in the
Laura Area, Majuro Atoll, Republic of the Marshall Islands,” USGS
Scientific Investigation Report 2005-5098, 2005, pp.1-40.
[8] USAID, “Adaptation to Climate Change: Case Study - Freshwater
Resources in Majuro, RMI,” 2009, pp.1-72.
[1] A. C. Falkland, “Hydrology and Water Management on Small Tropical
Islands, Hydrology of Warm Humid Regions (Proceedings of the
Yokohama Symposium),” IAHS Publication No.216, 1993, pp.263-303.
[2] S. S. Anthony, and L.F.Peterson, et. al., “Geohydrology of the Laura
Freshwater Lens, Majuro Atoll: A Hydro-geochemical Approach,” GSA
Bulletin, Vol.101, No.8, 1989, pp.1066-1075.
[3] S. S. Anthony, “Techniques for Appraisal of Groundwater Resources on
Atoll Islands: Case Studies from Micronesia,” Tropical Hydrology and
Caribbean Water Resources American Water Resources Association,
1990, pp.291-300.
[4] W. Guo, and D. L.Christian, “User’s Guide to SEAWAT: A Computer
Program for Simulation of Three-Dimensional Variable-Density
Ground-Water Flow,” USGS Techniques of Water-Resources
Investigations 6-A7, 2002, pp.7-18.
[5] K. Koda, and T. Kobayashi, et al., “Estimation of Hydraulic Parameters of
Laura Lens Aquifer (Japanese),” Journal of the JSIDRE, Vol.81, No.7,
2013, pp.541-545.
[6] K. Koda, and T. Kobayashi, et al., “Situation of the Freshwater Lens in
Laura Islands, Majuro Atoll, the Republic of the Marshall Islands
(Japanese),” Journal of the Japanese Geothechnical Society, Vol.62,
No.682/683, 2014, pp.30-33.
[7] K. T. Presley, “Effect of the 1998 Drought on the Freshwater Lens in the
Laura Area, Majuro Atoll, Republic of the Marshall Islands,” USGS
Scientific Investigation Report 2005-5098, 2005, pp.1-40.
[8] USAID, “Adaptation to Climate Change: Case Study - Freshwater
Resources in Majuro, RMI,” 2009, pp.1-72.
@article{"International Journal of Biological, Life and Agricultural Sciences:71594", author = "Kazuhisa Koda and Tsutomu Kobayashi", title = "Sustainable Use of Laura Lens during Drought", abstract = "Laura Island, which is located about 50 km away from
downtown, is a source of water supply in Majuro atoll, which is the
capital of the Republic of the Marshall Islands. Low and flat Majuro
atoll has neither river nor lake. It is very important for Majuro atoll to
ensure the conservation of its water resources. However, upconing,
which is the process of partial rising of the freshwater-saltwater
boundary near the water-supply well, was caused by the excess
pumping from it during the severe drought in 1998. Upconing will
make the water usage of the freshwater lens difficult. Thus,
appropriate water usage is required to prevent up coning in the
freshwater lens because there is no other water source during drought. Numerical simulation of water usage applying SEAWAT model
was conducted at the central part of Laura Island, including the water
supply well, which was affected by upconing. The freshwater lens was
created as a result of infiltration of consistent average rainfall. The lens
shape was almost the same as the one in 1985. 0 of monthly rainfall
and variable daily pump discharge were used to calculate the
sustainable pump discharge from the water supply well. Consequently,
the total amount of pump discharge was increased as the daily pump
discharge was increased, indicating that it needs more time to recover
from upconing. Thus, a pump standard to reduce the pump intensity is
being proposed, which is based on numerical simulation concerning
the occurrence of the up-coning phenomenon in Laura Island during
the drought.", keywords = "Freshwater lens, islands, numerical simulation,
sustainable water use.", volume = "9", number = "12", pages = "1253-4", }