May 1999  

In this issue:

Schofield Barracks Effluent Reuse Study

Sponsoring Agency:
Department of Defense, US Army Corps of Engineers - Waterways Experiment Station
July 1, 1998 to August 31, 1999


There is general agreement that Oahu should adopt reclaimed wastewater irrigation in order to conserve the limited groundwater resources upon which the island is totally dependent for potable water. The Hawaii State Department of Health (DOH) promotes the reuse of wastewater in accordance with their "Guidelines for the treatment and use of reclaimed water" which prescribes treatment requirements, and acceptable uses and practices.

The US Army's Schofield Barracks Military Reservation in central Oahu includes a wastewater treatment plant which discharges some 2.8 millions of gallons of secondary effluent daily. Under an agreement with Dole Foods (formerly Waialua Sugar) this effluent is piped into an irrigation flume at the outlet of nearby Lake Wilson. This water is then used for irrigation of agricultural fields downstream. Thus, there is already de-facto irrigation with reclaimed wastewater in central Oahu. The Army has a seven-year contract with Dole for this arrangement, scheduled to end in 2001. Therefore the Army is exploring the feasibility of alternative long-term, cost-effective methods of disposing of this effluent, including using it for irrigation of two nearby military golf courses, Leilehua and Kalakaua. The Army has decided to apply for a permit to use reclaimed water on these golf courses. As part of their application they discussed the matter with the DOH and it was agreed that the current study should be done.

Schofield lies within the "no pass zone" some 600 feet over a very important potable aquifer. The need to protect the aquifer from contamination is obviously of paramount importance. The potential for contamination to occur beneath wastewater irrigation is dependent on numerous parameters, many of which are site specific. Dr. Roger Babcock's project is designed to assess the risk of such contamination beneath the military golf courses.


Some secondary (R-2) effluent from the Schofield plant undergoes additional treatment (sand filtration and UV disinfection) to meet the State's R-1 standard for irrigation. This R-1 water is being applied to unirrigated areas adjacent to Kalakaua golf course fairways. For purposes of comparison, R-2 water is being applied to similar areas on the Leilehua course. A small, solar-powered, irrigation system (see Figure 1) has been installed at each of the courses.

Each system is on a timer that controls the amount of irrigation water delivered to a single regular pop-up lawn sprinkler. Lysimeters (soil water samplers) have been installed beneath the sprinkler at each of the test sites: one at a depth of four feet and two at two feet. Eight additional control lysimeters are strategically located on irrigated fairways around the golf courses. Water from all the lysimeters is sampled on a regular basis, and this water is analyzed for a number of parameters (see Table 1). In practice it is expected that irrigation with effluent will not exceed the consumptive use of the turf; however, this would mean that water would only reach the lysimeters during heavy rainfall events. Therefore, at intervals, the areas around the sprinklers may be inundated with potable water to simulate a large rainfall event that could be expected to flush any contaminants down through the vadose zone.

Data obtained from the lysimeters will be supplemented with pan evaporation and rainfall data to create a water balance with which to estimate/predict the potential impacts of a reclaimed water irrigation program on the underlying aquifer. A 3-D model (FEMWATER) will be employed to predict transport through the deep unsaturated zone and into the potable aquifer beneath the site. The effect on the growth and appearance of the turf will also be evaluated.

Table 1. Parameters Monitored

DOH-prescribed parameters

specific conductivity chlorides total phosphorus field pH nitrate/nitrite nitrogen
field temperature total Kjeldahl nitrogen total suspended solids total dissolved solids .

Additional parameters (to be done at least once during the project)

arsenic copper turbidity selenium
antimony barium lead beryllium
chromium cadmium thallium alkalinity
mercury boron fecal coliform fecal streptococcus
trace organic compounds total organic carbon BOD5 COD

Researcher Profile - Dr. Roger Babcock

This issue of the WRRC Bulletin is devoted mainly to the activities of Dr. Roger Babcock. Dr. Babcock joined WRRC in September of 1995 and has been very actively engaged in a number of research projects, in addition to his duties as Professor of Civil Engineering. Roger sits on the thesis committees of many students. He is also in charge of WRRC's toxics chemistry laboratory, located in Holmes Hall at the University of Hawaii at Manoa.

Dr. Babcock received his bachelor's degree at U.C. Davis and his Ph.D. in Civil and Environmental Engineering from UCLA.


    Biological Water and Wastewater Treatment
    Biodegradation of Toxic/Hazardous Waste
    Adsorption Processes
    Water Reuse


    Phone: 956-7298
    Fax: 956-5014


Performance Evaluation for a Residential Wastewater Treatment System

Sponsoring Agency:
Best Industries USA
November 1997 to August 31, 1999


Many Hawaii residents are not hooked up to centralized sanitary sewer systems. People living in these areas rely on septic tanks or cesspools for their sewage disposal. The State Department of Health (DOH) estimates that there are some 185,000 cesspools (unlined holes in the ground) and 4,500 septic tanks (settling tanks with leach fields) in the state. Under ideal conditions cesspools and septic tanks can be an adequate way of disposing of sewage. Unfortunately in many cases in Hawaii the geology and topography are unsuitable for the siting of these units. The cost of connecting residences in remoter areas of the state to county sewer systems is prohibitive, and this is not a feasible solution in Hawaii's current economic climate.

In the absence of any alternative, people install cesspools and septic tanks. The result is that there are large numbers of poorly performing individual sewage disposal systems throughout the state, leading to inadequate treatment of human waste, contamination of ground and surface waters, and in some cases raw sewage seeping onto the ground surface. Because this situation poses a considerable risk to public health, and the DOH has set a goal of eliminating septic tanks/cesspools in the state.

One interesting solution, which is being successfully employed on the mainland and in Japan, is the use of individual residential package wastewater treatment units. The manufacturers of these units claim that they provide treatment of ordinary household sewage to secondary standards. Dr. Roger Babcock's research is focused on assessing and optimizing the performance of one such unit; Best Industries USA, model UCZ-5.


Testing of the Best Industries unit is being conducted in accordance with standardized procedures specified by the National Sanitation Foundation in "NSF Standard 40 for Individual Aerobic Wastewater Treatment Plants" Minimum performance for production of an NSF Standard 40 Class I effluent requires that the 30-consecutive-day mean effluent BOD5 and suspended solids be no greater than 30 mg/l. The current research is aimed at determining whether the Best Industries unit can achieve this level of performance, as well as nutrient removal capabilities. The test unit is situated at the City and County of Honolulu's Sand Island Wastewater Treatment Plant where a ready supply of municipal waste is available. Testing includes a six-month standard performance period during which 400 gallons of municipal sewage will flow through the unit each day. This flow rate is based on a family of four persons with each producing 100 gallons of sewage daily. Flow into the unit occurs during three three-hour periods each day in accordance with the NSF specifications. This interrupted flow pattern necessitates the addition of a pump, a holding tank, electronic valves, timers, and a programmable logic controller (PLC) to the unit.

In addition to this standard performance testing, the unit will be subjected to a two-month stress testing period during which real-world load conditions will be simulated. As with the standard performance test, the stress test follows a regimen prescribed by the NSF Standard 40. These stress tests basically vary the influent rate to the unit in ways that simulate several situations that could be expected to occur in the average household (multiple laundry loads and so on).

Instantaneous grab samples and 24-hour composite samples of influent and effluent are taken daily from the unit. Samples are analyzed for BOD5, suspended solids, volatile suspended solids, settleable solids, dissolved oxygen, pH, nitrogen, and phosphorus species.

Additional research is being conducted to determine the feasibility of creating a complete on-site water reclamation system. This involves the use of a small sand filter column and an in-line UV disinfection unit for production of R-1 quality reclaimed water. Bringing the effluent to R-1 standards would allow its use in surface or subsurface irrigation of yards, water features such as fountains, washing yards and sidewalks, and toilet flushing. Parameters to be monitored for this phase of the project include turbidity, UV transmittance, and fecal coliforms. Dose-response curves for the UV unit are being created with a collimated beam apparatus.


After five months of continuous operation and daily monitoring, the following averages represent the effluent quality of the UCZ-5 unit:

    BOD5 12.3 mg/L
    TSS 13.5 mg/L
    settleable solids 0.1 mL/L

Therefore the unit is producing effluent of a quality that exceeds the requirements of NSF Standard 40. As can be seen from the line graph at right, the BOD5 of the effluent is much reduced by the treatment it underwent in the Best unit. The unit is capable of producing a consistently high-quality effluent from an influent of variable quality.


The Best Industries unit being tested has performed well, without maintenance, over the five months that it has been online. However, these units do require periodic maintenance consisting of pumping out the sludge, servicing the air pump in the aerobic digestion chamber, and backflushing to clean off the media. People are notoriously bad at maintaining their cesspools and septic tanks, and it is likely that maintenance of systems like the Best Industries unit will be similarly neglected by the average homeowner. The required maintenance may be beyond the capabilities of many homeowners to perform themselves. It is understood that in Japan owners of these units pay a flat rate to the wastewater department, similar to the sewer charge that we pay in Honolulu. This fee entitles them to periodic maintenance and emergency service of their units. Therefore the adoption of this technology as a solution to the problems posed by the cesspools in Hawaii would require the simultaneous development of a maintenance network.

WRRC Graduate Researchers Participate in Recent HWEA Conference

Several WRRC research assistants presented posters at the annual Hawaii Water Environment Association conference which was held in Honolulu in the first week of March.

Ms. Jody Murata, MS student in Civil Engineering, produced a poster illustrating her research on Bioavailability of toxic organics in harbor sediments. This project looks at a method of determining the toxicity of contaminated soils. The research involves using supercritical carbon dioxide to extract chemicals from soil samples, and then testing the toxicity of these chemicals. To do this Ms. Murata is assessing several solvents and mediums to trap the chemicals during the extraction process, for ease of use with the Microtox assay. The Microtox system uses a type of bacteria which lights up under UV light when alive. Bacteria exposed to fatal doses of chemicals no longer light up. By measuring the light emitted by test tubes full of these bacteria, exposed to various concentrations of a chemical, one can determine the toxicity of that chemical. Ms. Arlene Sagayaga and Mr. Keith Oshiro, also master's degree students in Civil Engineering, presented posters describing projects looking at water quality parameters in some traditional Hawaiian fishponds on Molokai, Lanai, and Oahu. These ponds are currently being restored in order to return them to their function of raising fish. In order to get government approval for the restorations, water quality testing must be done. Those restoring the ponds hope to find an easy way to do this. Mr. Oshiro's work focused on assessing the equivalency of field-kit testing to standard EPA laboratory tests. Ms. Sagayaga's work focused on comparisons of water quality inside and outside the ponds in relation to State water quality criteria. More information about the fishpond restoration project can be seen at

Civil Engineering master's degree candidates Mr. Dan McNair and Mr. Lance Edling presented a poster describing experiments to assess the performance of the Best Industries individual residential wastewater system described elsewhere in this bulletin.

Master's degree candidate Dean Shirota presented a poster on a project that assessed the microbial quality of groundwater in the so-called caprock aquifer in Ewa. This study is being done to establish baseline quality parameters in advance of the land application of reclaimed Honouliuli Treatment Plant wastewater planned by the City and County of Honolulu.

The student researchers posters were well received at the conference, and cash prizes totaling $200 were awarded to the WRRC students. The posters are now on display in the WRRC offices in Holmes 283.

Hiroshi Yamauchi Retires From UH

Dr. Hiroshi Yamauchi, who was a joint WRRC/Agricultural Economics faculty member, retired this semester after 30 years of service to the University of Hawaii. Dr. Yamauchi was a great asset to the water center. His frequent collaborations with colleagues in Japan helped establish WRRC's friendly relations with water researchers at several universities in that country.

On March 16th a party was held in Sherman Hall to congratulate Dr. Yamauchi on his retirement and celebrate his achievements over the years. Dr. Yamauchi assured us that he will be in contact with us, and available to help with future projects.

WRRIP Is Underfunded But Back On Track

Director's Message: Dr. Roger Fujioka

The Water Resources Research Institute Program or WRRIP is the federal program which has funded a "Water Center" at the Land Grant University in every state since 1964. The Water Resources Research Center (WRRC) at the University of Hawaii is the Water Center for the state of Hawaii. From 1966 to the mid 1980s the federal government clearly supported the WRRIP and as a result, funding was available to meet the WRRIP mission of training future water resources scientists and conducting needed research to address critical water-related problems in the state of Hawaii.

During those years, funding was allotted to each state water center and a separate funding program was available to address water problems on a regional basis. However, during the Reagan, Bush and Clinton presidency, the federal government no longer included funding for the WRRIP, and the directors of each water center worked with their Congressional Delegates in a successful campaign to have Congress fund WRRIP. Although successful in this endeavor, the funding level for WRRIP has been systematically reduced from $10,776,000 in FY 1991 to $4,553,000 for each of fiscal years 1995-1998. In summary, we have Congress to thank for maintaining the WRRIP during the difficult years. Part of the price we paid was the reduced funding level.

We learned that Congress is run by powerful committees. In 1996, a powerful committee succeeded in derailing the mission of WRRIP by mandating that research funds under WRRIP would no longer be allotted to each state, and placed this money into a regional grant program. The centers were required to compete with each other for these funds to address regional water problems rather than state water problems. This program benefited only a few water centers, and placed the island water centers (Hawaii, Guam, Puerto Rico, Virgin Islands) at a disadvantage since water problems in individual islands did not fit into the established regions of the continental USA (islands are not recognized as a region). This mandate by Congress contradicted the original mission which led to the formation and operation of the WRRIP. Each year thereafter the directors of all the Water Centers petitioned Congress to return funding for research back to each state and to increase the funding level of WRRIP so state water problems could be addressed. The breakthrough occurred for the FY 1999 budget when Congress approved the following changes:

    1) Return research funding and authority to each state Water Center.
    2) Increasing the WRRIP budget from $4,553,000 to $5,057,000.
    3) Allotting a separate $1,000,000 for a national competitive grant program to address regional water problems.

I wish to point out that all of these changes are the direct result of Congress and the active yearly request made by Water Center's Directors to the state Congressional Delegates. In this regard, all four of Hawaii's Congressional delegates (Senators Inouye and Akaka, and Representatives Abercrombie and Mink) have always supported the WRRIP and have played critical roles in maintaining and finally in improving the conditions of WRRIP. Today, the WRRIP is back on the track it wants to be and heading in the right direction. However, funding for each water center has been reduced from approximately $110,000 in 1991 to only $68,178 in 1999. Of the $68,178, 78% or $53,273 is used to support two research projects, 13% or $8,905 is used to support WRRC technology transfer program and only 9% or $6,000 is used for administrative costs, including travel costs to attend the WRRIP meetings. This limited amount of funding is insufficient for WRRC to meet the WRRIP mission of conducting the necessary research to address the critical water related problems in the state of Hawaii. To meet this challenge, WRRC will implement the following four-step plan:

1. Continue to urge Congress to increase funding for WRRIP. This is much more likely to happen because WRRIP is now being supported by Congress, its parent organization (USGS), and the nation's economy is good. However, this option is currently limited by a Congressional Rule called "capping" which limits the amount of money Congress can spend for programs such as WRRIP which come under the category of "non-defense, discretionary funding". In practical terms, Congress must raise the ceiling of the cap before more money can be added to WRRIP. This is being pursed with Hawaii's Congressional Delegates.

2. Establish an Island Region for Water Centers. The island water centers have had difficulty in trying to fit into regions established for the continental USA. During this past year, the four island water centers (Hawaii, Guam, Puerto Rico, Virgin Island) petitioned the National Institute for Water Resources to allow all the island centers to form a single region based on commonality of climate, hydrology, geology and ecology. This petition was approved and will be implemented. The formation of an island region will now clearly establish that island water problems are of a regional nature. For many grants, fitting into a regional or national need is a pre-requisite to being funded.

3. Reorganize and Involve WRRC Technical Advisory Committee. Since authority to fund research projects has been returned back to the state Water Center, WRRC will reorganize the WRRC Technical Advisory Committee, which in the past has been used to set the research agenda for WRRC. Letters of invitation have been sent to all the agencies in Hawaii with authority or expertise in addressing the water-related and environmental problems in Hawaii. A meeting of this committee is being planned during the summer of 1999 to establish the research agenda for the next 5 years and to establish guidelines for closer working relationships with other agencies in Hawaii with that of WRRC.

4. Seeking Matching Grants to Expand the Capability of WRRIP. Funding of research projects under WRRIP requires a matching of $2 for every $1 federal funds. WRRC will seek agency support to match funding to this WRRIP program so as to leverage the federal funding program to obtain supplemental funding to be able to adequately complete research projects. In this regard, the agency supplying the matching funds will gain access to matching funds and the commitment of a dedicated scientist from the University of Hawaii who will be providing considerable expertise with no additional costs.

International Workshop on Environmental Information Exchange

During the last week of April, WRRC faculty participated in a workshop sponsored by the UH School of Public Health. The workshop was held for the Pollution Control Working Group of the China Council for International Cooperation on Environment and Development. The delegates of this group are mid- to high-level representatives of environmental management agencies from the People's Republic of China. The head of the delegation was Professor Qu Geping, Chairman of the Environment and Resource Protection Committee of the Chinese National People's Congress. The workshop was intended to showcase environmental conditions and protection activities in Hawaii as well as the state's capacity in the areas of air, water quality, watershed, and land use management. A consortium of Hawaii's environmental management experts has recently come together under the leadership of the UH School of Public Health with the goal of providing further short- and long-term training, technical consultation, and research collaboration for Chinese pollution control program managers. This consortium includes members of the WRRC faculty. During the five-day workshop WRRC faculty gave presentations regarding water-borne diseases and pollution monitoring, as well as drinking water treatment issues and technologies.