A reader asks: What is happening with the state’s desalination plant at the Campbell Industrial Park on O`ahu?
Construction of the plant was completed in August 1990 at a cost of $6.2 million. Campbell Estate contributed $2 million and land. The remainder was paid for by the state. Planning and designing the plant cost $554,770. Drilling the caprock and basal “feedwater wells” added $1,427,000 to the facility’s expense, making the total cost come to some $8.2 million.
Water from the facility — 200,000 to 250,000 gallons per day — is fed into the City and County of Honolulu Board of Water Supply system. The cost of producing the water is more than $10 per thousand gallons. The BWS, however, pays the state nothing.
When the plant was proposed, the idea was that the Board of Water Supply would operate it. The 1.25 million gallons of fresh water that the plant was designed to produce each day would be fed into the city’s municipal water delivery system. Campbell Estate, for its part, would receive up to 1 million gallons a day in water credits from the city for projects in the `Ewa region that the estate had planned. The state’s interest in all this would be to have a working desalination plant that made use of three separate technologies for removing salt from water: reverse osmosis, electrodialysis, and electrodialysis reversal.
Not as Planned
The tri-party agreement spelling all this out was never signed. A December 28, 1992, memorandum from Manabu Tagomori, director of the state Department of Land and Natural Resources’ Division of Water and Land Development, to DLNR Chairman William Paty attempts to explain the Board of Water Supply’s reluctance to participate in the project: “We [DOWALD] went to a contract operation because in late 1990 BWS indicated it did not want to operate the plant until the agreement was approved by the Board and City Council.” And even if BWS signed the agreement, it might still desire to have a contractor run the plant, Tagomori said, until a decision was reached to have the city accept the plant, since the Board of Water Supply did not want to have to layoff employees should it not be running the plant indefinitely.
Up until last year, DOWALD continued its efforts to get the Board of Water Supply to participate. Those efforts were ultimately frustrated by the Board of Water Supply’s insistence that the state provide a backup source of potable well water.
Finally, in June 1994, Tagomori presented to the Board of Land and Natural Resources a request that the state enter into a two-party agreement — with Campbell Estate — covering operation of the desal facility.
The agreement provides for the state to give Campbell Estate “potable water from the Board of Water Supply … equivalent to an allocation of 1.0 MGD [million gallons per day] average day capacity for use” in certain projects of the estate. The state “intends to meet its obligations … from its source development program with the BWS,” the agreement states.
According to Alyson Yim of DOWALD, Campbell Estate has not been getting its 1 million gallons a day. Production of fresh water from the desal facility, which has been fed into BWS lines since mid-1992, has not come close to the 1.25 million gallon daily capacity projected. Instead, production comes closer to about 1.25 million gallons per week, or 250,000 gallons per day.
Promises, Promises
The agreement makes allowance for the state’s inability to deliver the promised water: “The Estate understands that the water commitments are not currently available to the state… However, the State agrees to make deliberate efforts to fund the requirements for said water commitments at the earliest possible date and to continue those efforts for funding until the full satisfaction of the water commitment… In order to fulfill its obligations to the Estate, the State agrees to set aside for the Estate’s benefit from the State’s proposed Leeward Well and each subsequent potable water source developed by the State on O`ahu the lesser of (I) 250,000 gallons per day or (II) twenty-five percent of the actual capacity in each such water source which the BWS determines may be allocated until the full potable water commitment of 1.0 MGD has been satisfied. Furthermore, the State agrees to provide the Estate its full potable water commitment of 1.0 MGD average day capacity no later than December 31, 1998.”
If the water commitment cannot be fulfilled, the land and the feed wells will revert to Campbell Estate, and the estate will be offered the right of first refusal for purchase of the plant.
M&E Gets O&M
When the Board of Water Supply elected not to participate, DOWALD selected a contractor, M&E Pacific, Inc., to operate and maintain the facility. From February 1991 through June 1995, M&E will have received $1,755,000 for this work.
M&E Pacific never had to bid on the operation and maintenance contract. That contract, in fact, is but a continuation of the original non-bid design contract for the plant, issued in 1987 to Mitsunaga & Associates, with M&E Pacific as the chief subcontractor. The initial design work came to $337,350. Five “Supplemental Agreements” increased the total contract to $2,092,350, which covers work through June 30 of this year in addition to $155,000 for preparation of an operations manual.
Operation of the plant has not been problem-free. From August 1992 to January 1993, the plant did not operate at all because of equipment breakdowns.
Well Problems
Five wells were drilled to provide source water to the plant. One well takes water from the basal aquifer. Four wells were drilled into the caprock aquifer. Comparing efficiencies in treating basal and caprock water was to be an important element in the “demonstration” of desalination processes, which was the purpose of the plant.
A host of difficulties has attended the caprock wells. The caprock well at the plant site was not able to produce enough water to satisfy production needs. Three more caprock wells were drilled off-site. Because of a surveying error, the first two were in the wrong location. One of those was sealed; the other one, as well as the third off-site caprock well, continue to be regarded as potential sources of feed water. According to DOWALD’s Yim, the state did not pay for the surveying error; either Campbell Estate, which was responsible for the surveying, or the contractor paid, but not the state, Yim said.
When would a permanent hook-up be made between the plant and a caprock source? Yim’s best guess was sometime in the next six months.
As a result of the delays in bring the caprock water source into the plant, practically all of the water treated has been from the basal aquifer, where salinity levels are much lower.
(Typically, chloride levels in the caprock water range from 600 to 700 parts per million; the basal well used as a source by the desalination facility shows chloride levels of 500 to 550 parts per million. Neither the caprock nor the basal feed water is so brackish as to be unfit to drink without treatment. While no state maximum contaminant levels for chloride exists, Los Angeles has a standard of 550 ppm. Many countries have standards that are 1000 ppm. In fact, several years ago, when Maui County had to use coastal wells to supply water to West Maui after a landslide took out its primary source of mountain water, salinity in the domestic water system approached 800 ppm — so salty, in fact, that plants irrigated with the water began to wither.
(In Honolulu, the Board of Water Supply has adopted a standard of 160 ppm chloride in the distribution system. According to Erwin Kawata of the BWS, some individual sources of water may have chloride content of up to 250 ppm, but that saltier water is blended with fresher water so that what comes out of the tap has a chloride content of no more than 160 ppm.)
Finally, the use of relatively sweet water in the desalination process may undermine the very point of the plant, which is, after all, to demonstrate the efficiency of three different processes in removing salt from water with a high chloride content. As one University of Hawai`i researcher put it in a memo to DOWALD, the “existing well turned out to be ‘sweeter’ than expected; hence perhaps current experience tells us less than we think.”
The Bottom Line
The desalination plant was originally supposed to be in operation 24 hours a day, seven days a week (except for maintenance). Since it began operation, however, it has run at most eight hours a day, five days a week. For this reason, the cost of water produced by the plant is far higher than anything the Department of Land and Natural Resources predicted.
In July 1993, M&E Pacific provided the Division of Water and Land Development with an evaluation of production costs. Excluded from the evaluation were capital costs (land acquisition and construction). Still, all three processes in place at the plant had production costs in excess of $7.00 per thousand gallons. What’s more, had the treated water not been blended, in an 85/15 mix, with untreated water, production costs would have been even higher.
By comparison, non-commercial customers receiving water from the Board of Water Supply pay $1.65 per thousand gallons.
When capital costs are added into the desalination expenses, the figure rises substantially. Yim acknowledges that $10 per thousand gallons is a conservative figure.
One University of Hawai`i graduate student, Ravindra B. Gogineni, undertook an extensive study of the desalination plant costs. His conclusion (based on data available in 1991) was that the product water cost $15.84 per thousand gallons.
Although conventional wisdom holds that costs rise as production falls, this is not necessarily the case with desalination. The Kona Village Resort, on the arid Kona Coast, has been operating two small desalination plants, with a combined production of 70,000 gallons per day, since the mid-1970s. According to the resort’s engineering chief, the cost of producing the water is about $5 per thousand gallons.
Volume 5, Number 10 April 1995