RESEARCH: HYDROLOGICAL SCIENCES

Demonstration Study of High-Rate Flotation/Contactor Treatment of Raw Wastewater

SPONSOR:
R.M. Towill Corporation

PROJECT PERIOD:
03/01/2016-02/28/2017

ABSTRACT:
The Honouliuli Wastewater Treatment Plant (HWWTP) is the second largest treatment plant in Hawaii. At HWWTP, an average of 26 million gallons per day (MGD) of sewage is treated via primary clarifiers and then 13 MGD is further treated
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Removal of Nitrogenous Aquaculture Wastes by a Wind Powered Reverse Osmosis System

SPONSOR:
U.S. Geological Survey

PROJECT PERIOD:
Year 1: 03/01/01 – 02/28/02
Year 2: 03/02/02 – 02/28/03

ABSTRACT:
Tilapia fish are a major source of protein around the world. In the United States, tilapia farming is the fastest growing segment of aquaculture, and over the last year, domestic
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Sequential Anaerobic-Aerobic Biodegradation of PCBs and PAHs in Phytoremediation Cuttings Using Slurry Reactors and Composters

SPONSOR:
Environet, Inc.

PROJECT PERIOD:
05/01/02 – 10/31/03

ABSTRACT:
The use of phytoextraction for clean-up of soils contaminated with heavy metals is an attractive alternative to excavation and treatment/removal operations that is quite well documented (Raskin, 2000). The use of plants to extract toxic organic compounds such
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Removal of Nitrogenous Aquaculture Wastes by a Wind-Powered Reverse Osmosis System, Year 2

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2002 – 2/28/2005

ABSTRACT:
Advanced treatment must be provided to wastewater used for freshwater aquaculture in order to meet effluent water quality standards. Because such treatment can be expensive and because freshwater is also
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Development and Implementation of a Water Monitoring Plan to Prepare for Criminal and Terroristic Contamination of a Drinking Water System

SPONSOR:
Honolulu Board of Water Supply

PROJECT PERIOD:
2/15/02 – 12/31/04

ABSTRACT:
The recent acts of terrorism in the U.S. have clearly shown that agencies in the U.S. and throughout the world are not prepared to defend against terroristic acts on their citizenry. As a result, agencies
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An Accurate Evaluation of Water Balance to Predict Surface Runoff and Percolation

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/02 – 2/28/05

ABSTRACT:
Hawaii, like many other states, has a number of unlined landfills that are potential groundwater contamination sources. Infiltration control is a major means of reducing leachate generation at unlined landfill
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Prevention of Colloidal Fouling in Crossflow Membrane Filtration: Searching for Optimal Operation Conditions Year 2

SPONSOR:
U.S. Geological Survey

PROJECT PERIOD:
03/01/03 – 02/28/05

ABSTRACT:

Crossflow membrane filtration processes involving reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF), and microfiltration (MF) have steadily gained importance in environmental engineering separations over the past decade. Numerous improvements in the technology have spurred widespread adaptation
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Wind-Powered Reverse Osmosis Water Desalination for Pacific Islands and Remote Coastal Communities

SPONSOR:
US Bureau of Reclamation (USBR)

PROJECT PERIOD:
10/01/04 – 06/30/06

ABSTRACT:
Water and energy are closely linked natural resources – the transportation, treatment, and distribution of water depends on low-cost energy; while power generation requires large volumes of water. Seawater desalination is a mature technology for
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Evaluating the Effectiveness and Feasibility of Commercial Ozone Technologies Used for Sanitation of Work Area and Laundry Services

SPONSOR:
U.S. Army

PROJECT PERIOD:
09/01/05 – 12/31/06

ABSTRACT:
The primary goal of this study was to obtain independent, laboratory-based, performance data to evaluate the effectiveness, feasibility and safety in the application of one commercial ozone technology (Ozone Industries, Inc.) for cleaning and disinfection of workplace surface
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Diffusive Tortuosity of Reactive Porous Media: Application to Colloidal Fouling and Biofouling During Membrane Filtration

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2005 – 2/28/2006

ABSTRACT:
Fouling in microfiltration (MF) and ultrafiltration (UF) processes has been extensively studied for the crossflow filtration technique in which the flow direction is parallel to the membrane surface but perpendicular
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Development of a New Technique for the Use of Dissolved Helium as an Environmental Groundwater Tracer

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2005 – 2/28/2006

ABSTRACT:
Tracer tests are an important method for determining the flow characteristics and patterns of subsurface water (such as groundwater aquifers) and surface water bodies (such as streams and the ocean).
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RAM2 Modeling and the Determination of Sustainable Yields of Hawaii Basal Aquifers

SPONSOR:
Hawaii Commission on Water Resources Management (CWRM)

PROJECT PERIOD:
2006 – 2008

ABSTRACT:
Basal aquifers, in which freshwater floats on top of saltwater, are the major freshwater supply for the Hawaiian Islands, as well as many other coastal regions around the world. Under unexploited or natural
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Influence of Soluble Organic Matter on Cryptosporidium Parvum Oocyst Mobility in Variable Charge Soils

SPONSOR:
USDA

PROJECT PERIOD:
07/15/06 – 07/14/09

ABSTRACT:

Cryptosporidia are pathogenic protozoa that are present in the digestive tracts of a wide range of vertebrates. Runoff water can carry Cryptosporidium oocysts (a tough dormant form) from manure to source waters (such as rivers and lakes). If
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Survey and Modeling Analysis of MS4 Highway Storm Runoff on Oahu, Hawaii

SPONSOR:
Hawaii Department of Transportation

PROJECT PERIOD:
09/01/08 – 08/31/10

ABSTRACT:
Under Section 402 of the U.S. Clean Water Act, highway storm runoff is considered to be part of urban point source pollution and is regulated by the National Pollutant Discharge Elimination System (NPDES). As a NPDES
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Determination of the Relationship Between Biodiversity and Trophic Status of Wahiawa Reservoir

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
Nutrient enrichment in rivers and lakes has been a changing phenomenon in the past three decades in the United States. Contribution from point sources, such as wastewater discharge, has been
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Modeling and Drainage Design for the Kaloi Gulch Watershed in Southern Oahu – Phase II

SPONSOR:
R.M. Towill Corporation

PROJECT PERIOD:
05/27/08 – present

ABSTRACT:
Haseko (Ewa), Inc. proposed an 1,100-acre development at the lowermost reaches of the Kaloi Gulch watershed on Oahu, Hawai. According to the City’s storm drainage standard, the 100-year storm peak flow at the lowermost reaches of the
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Improving Water Resource Assessment in Hawaii by Using LiDAR Measurements of Canopy Structure to Estimate Rainfall Interception

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
Water resources in Hawaii continue to experience increasing demand, putting pressure on existing sources and increasing the need for better estimates of resource capacity (Oki 2002). For ground-water sources, in
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Experimental Study of Humidification-Dehumidification (HDH) Seawater Desalination Driven by Solar Energy

SPONSOR:
USGS

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
relatively new desalination process called humidification-dehumidification (HDH) was proposed as a feasible solution to the freshwater shortage problem in Hawaii. HDH operates under near ambient pressure and low temperature and can be driven by renewable solar energy as well
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Determination of the Relationship Between Biodiversity and Trophic Status of Wahiawa Reservoir

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
Nutrient enrichment in rivers and lakes has been a changing phenomenon in the past three decades in the United States. Contribution from point sources, such as wastewater discharge, has been
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Application of Radar Imagery as Input to a Rainfall-Runoff Model for the Kawela Watershed, Molokai

SPONSOR:
USGS – WRIP

PROJECT PERIOD:
9/01/2008 – 12/31/2009

ABSTRACT:
Watershed-scale studies in Hawaii can integrate several aspects of basin hydrology, such as stream flow, ground-water recharge, pollutant transport, streambed erosion, and sediment discharge. In addition, the effects of rainfall or land cover changes on any of
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A Decision Support Tool for Managing the Pipe Network of the Honolulu Board of Water Supply

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2009 – 2/28/2010

ABSTRACT:
The development of asset management plans for public facilities was strongly recommended by the EPA and GAO. At the Honolulu Board of Water Supply (BWS), there was an apparent need
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Measuring Soil Water Content and Electrical Conductivity Under High Salinity Conditions Using a Novel TDR Method

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2010 – 2/28/2011

ABSTRACT:
Salt accumulation from irrigation is a significant and growing problem on many agricultural lands. The efficient operation of an irrigation system relies on, among other factors, the correct reading of
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A Decision Support Tool for Managing the Pipe Network of the Honolulu Board of Water Supply (Year 2)

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2010 – 2/28/2011

ABSTRACT:
Similar to numerous other cities, Honolulu’s municipal water systems has many aging and unreliable components. The Board of Water Supply contends with a number of water main breaks and leaks,
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Development of an Advanced Surface Tensiometer for Measuring Water Quality

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2011 – 2/28/2013

ABSTRACT:
Characterizing the physical, chemical and biological properties of potable and recreational waters plays a vital role in assessing and controlling water quality. The objective of this proposal was to develop
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Experimental Study of Humidification-Dehumidification (HDH) Seawater Desalination Driven by Solar Energy

SPONSOR:
USGS

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
A relatively new desalination process called humidification-dehumidification (HDH) was proposed as a feasible solution to the freshwater shortage problem in Hawaii. HDH operates under near ambient pressure and low temperature and can be driven by renewable solar energy as
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Improving Water Resource Assessment in Hawaii by Using LiDAR Measurements of Canopy Structure to Estimate Rainfall Interception

SPONSOR:
WRRIP 2008

PROJECT PERIOD:
03/01/08 – 02/28/09

ABSTRACT:
Water resources in Hawaii continue to experience increasing demand, putting pressure on existing sources and increasing the need for better estimates of resource capacity (Oki 2002). For ground-water sources, in particular, reliable estimates of sustainable yield limits are
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Quality Assurance Plan for Water Quality Monitoring During the Reconstruction and Aquaculture Operation of Traditional Coastal Fishponds on the Island of Molokai

SPONSOR:
U.H. College of Tropical Agriculture and Human Resources (CTAHR)

PROJECT PERIOD:
09/01/00 – 03/31/01

ABSTRACT:
CTAHR personnel have prepared a Quality Assurance Plan (QAP) for the U.S. Environmental Protection Agency (EPA) regarding the project “Water Quality Monitoring During the Reconstruction and Aquaculture Operation of Traditional Coastal
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Measuring Soil Water Content and Electrical Conductivity Under High Salinity Conditions Using a Novel TDR Method

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2010 – 2/28/2011

ABSTRACT:

Salt accumulation from irrigation is a significant and growing problem on many agricultural lands. The efficient operation of an irrigation system relies on, among other factors, the correct reading
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Fate and Transport of Pharmaceutically Active Compounds in Simulated Bank Filtration System

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2012 – 2/28/2013

ABSTRACT:
Riverbank filtration (RBF) represents a natural filtration technique that has been used for providing drinking water for more than a century in Europe and half a
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Acquire Sedimentation Data to Promote Reservoir Sustainability and Advance Watershed Science

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2012 – 2/28/2013

ABSTRACT:
Hawaii’s reservoirs face growing scrutiny due to heightened dam safety and flood control concerns, increasing water demands, and uncertain water pollution effects. Although the National Inventory
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Evaluation of Next-Generation Sequencing Technologies for Environmental Monitoring: Characterization of Microbial Communities from Wastewater Plants and Selected Beaches of Hawaii Using a Metagenomics Approach

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2013 – 2/28/2014

ABSTRACT:

Microbes are the most abundant and diverse group of organisms on Earth and the major drivers of biogeochemical cycles in all environments. Hence having an
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Evaluation of the Impact of Drought Conditions upon the Waiahole Ditch System Development Tunnels: Ground Water Sustainability Implications under Adverse Climate Change Conditions

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2013 – 2/28/2014

ABSTRACT:
Reductions in the base-flow discharges of the high-level development tunnels of the Waiahole Ditch System are believed to be associated with regional recharge distribution shortfalls to
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Monthly Rainfall Maps for the Islands of Kauai, Oahu, Molokai, Maui, and Hawaii, 2008-2010

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/2013-02/28/2014

ABSTRACT:

The Hawaiian Islands have one of the most diverse rainfall patterns on Earth. The mountainous terrain, the persistent trade winds, the heating and cooling of the land,
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Evaluation of Portable Multi-use Automated Concentration System (PMACS) for the analysis of indicator bacteria and microbial source tracking markers in Hawaii

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/2014-02/29/2016

ABSTRACT:

Problem and Research Objectives

Problem I: Distribution of microorganisms in beach water and sand is patchy. It is well established that distribution of microbes in the environment
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Geochemical Delineation of Aquifer Boundaries and Assessment of Groundwater Quality on Tutuila Island, American Samoa

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
07/20/2015-07/08/2017

ABSTRACT:

Deteriorating water quality and resulting water shortage is an ongoing threat to the sustainability of domestic water supplies on Tutuila, the main island in the territory of
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Identifying future hotspots for algal blooms: A multi-dimensional analysis evaluating impacts of potential land-based sources of pollution on the health of American Samoa’s coasts

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2016

ABSTRACT:
Land-based sources of pollution (LBSP) drive coastal algal blooms, growth of opportunistic seaweeds that can persist for years and in many parts of the world. In
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A Novel Approach for Estimation of Evapotranspiration

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2016

ABSTRACT:
Understanding of the amount, spatial distribution, and temporal variability of evapotranspiration (ET) in Hawaii is essential for assessment of water resource availability and management of water
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Numerical Simulation of Cold Intermediate Depth Seawater Circulation Through the Keauhou Aquifer in North Kona, Hawaii

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2016

ABSTRACT:
Recent drilling log and depth profile data acquired from boreholes drilled through the basal lens in the northern Keauhou aquifer suggest that cold, intermediate depth seawater
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Rainwater Harvesting in American Samoa: Current Practices and Health Risks

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2016

ABSTRACT:

Island ecosystems have low buffering capacity, hence are highly vulnerable to change. Shifts in rainfall and temperature driven by climate change can compromise available water
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Assessing Feasibility of Storm-Water Harvesting by Groundwater Injection in Nuuanu Reservoir No. 4, Oahu, Hawaii

SPONSOR:
Honolulu Board of Water Supply

PROJECT PERIOD:
07/20/2015-07/08/2017

ABSTRACT:
Surface water harvesting is a conservation method used to augment groundwater supply. The method is a form of Aquifer Storage and Recovery (ASR), which involves capturing excess water during wet periods and injecting
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Understanding the Hydrology of a Rainforest Watershed in Hawaii

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2017

ABSTRACT:

Recent studies have shown an increase in rainfall intensity in Hawaii. However, total rainfall has been on the decline in the last two decades and stream
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Understanding the Hydrology of a Rainforest Watershed in Hawaii

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2017

ABSTRACT:
Recent studies have shown an increase in rainfall intensity in Hawaii. However, total rainfall has been on the decline in the last two decades and stream
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Identifying Groundwater Flow and Contamination to Streams: Kahaluu Watershed, Oahu

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2017

ABSTRACT:
The surface waters in the Kahaluu Lagoon on the windward side of Oahu fronted by Kaneohe Bay have been shown to have very high levels of
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Tsunami Observer Program

SPONSOR:
Department of Defense, State of Hawaii (Civil Defense Division)

PROJECT PERIOD:
03/01/2010-ongoing

ABSTRACT:

The mission of the Tsunami Observer Program (TOP) is to obtain accurate measurements of water run-up (elevation above mean sea level) and inundation distances resulting from tsunami waves for
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2015 WRRC Capacity Building and Science Communications for Groundwater Sustainability Work in American Samoa

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
3/1/2015 – 2/28/2016

ABSTRACT:
The sustainability of groundwater use on Tutuila, the main island in American Samoa, is currently in question. Water demand is increasing and the island’s aquifers are
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Microbial communities and sources of bacteria in Honolulu’s water supply

SPONSOR:
National Institute for Water Resources, Water Resources Research Institute Program

PROJECT PERIOD:
03/01/2015-02/29/2017

ABSTRACT:
The overarching goal of the project is to characterize microbial communities and sources of microbes in Honolulu’s water supply. This is the first in-depth analysis of microbes in
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