County wastewater chief: Small plants may be better

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WAILUKU - For decades, the county has contemplated addressing several wastewater issues by building a big, centralized treatment plant inland. The cost of nearly half a billion dollars has always kept the idea on the shelf.

But now, thanks to technological innovations and the gradual creation of a private wastewater service business, there may be a third way: Dave Taylor, the head of the Wastewater Reclamation Division in the Department of Environmental Management, says the third way - small, private "package" plants - is not only feasible but in many ways desirable.

There is no urgency to expand the county's sewage treatment plants in Kahului, Kihei or Lahaina, which have unused capacity to last for years. Nor is there any practical possibility of expanding county sewerage to unserved and thinly built-up areas of the county.

But package plants could be a practical solution even for quite small developments of a few hundred houses, says Taylor. John Wilkinson, sales managers of WSI International LLC in Honolulu, which sells package plants, says his company just delivered a plant for only 20 homes on the Big Island, and WSI is introducing single-family plants that replace septic tanks.

Charlie Jencks, who is developing Honua'ula in South Maui, is planning to build a package plant for the wastewater, but if county collection lines ever get to his project, he will close the plant and hook up to municipal services.

It's not a matter of cost, he said, but of regulation. As a former county director of public works, he says the consequences of dealing with state and federal regulators if there is a spill are not worth the headaches.

"It ain't pretty."

For years, the state Department of Health did more than frown on package treatment systems. Bad experiences at Maalaea and Kihei in the '80s contributed to the disfavor. However, Tom See, the head of the Wastewater Branch in the DOH, said that package plants were legal then and are legal now.

Developers have to show that they can meet effluent standards. Now they really can.

Taylor says that in the old days, package plants for condominiums were left in the care of facilities managers, who had no training in maintaining them. It's a skilled job, and too often the supposed "treatment plant" turned into a big, dysfunctional septic tank - right on the shoreline.

Today, the plants are better designed, can be monitored by computers and overseen by trained operators. (See related story.)

"The technology really has changed," says Taylor. The new plants "are very reliable and produce very high-quality wastewater."

There are many manufacturers, and all use the same basic approach: Microbes feast on the polluted water, with plenty of air. The county plants do the same thing, on a bigger scale (around 5 million gallons a day at each of the three plants).

Advantages claimed for package plants include:

Few or no odor problems. Controlling odor is mainly a matter of age, says Taylor. The older it is, the more it smells. Central plants with long collection lines age the sewage. Local plants with short lines get the incoming sewage treated before it has a chance to stink.

Big savings in collection lines. Steve Parabicoli, who supervises reclaimed water reuse for the county, says laying pipe in Kihei costs $250-$300 a foot. This frustrates him, because he has high-quality (R1) effluent that could be used for irrigation, but the potential customers are far away. So the effluent is disposed of in injection wells.

If it could be reused, it would help the Department of Water Supply by displacing the use of treated drinking water to water lawns, and the Wastewater Reclamation Division by generating revenue.

With a package plant, the effluent can be used on the spot to irrigate lawns and roadsides. Developer Jesse Spencer, who is proposing to build a 1,000-house development at Maalaea, plans to build a package plant and use the effluent to water ballfields and a greenbelt on the dry hillside above the property.

Wilkinson said a WSI plant easily beats even the strictest California standards for both biological oxygen demand and chemical oxygen demand, as well as denitrifying the effluent. R1 quality effluent is easy, he said.

R1 is the highest-quality effluent, approved for most uses except drinking after being filtered, treated and disinfected. The Lahaina and Kihei county plants produce R1 water. Kahului produces R2 but could be upgraded to R1 with the addition of ultraviolet light disinfection.

Big savings in power. Sewage treatment plants are usually located as low as possible, to take advantage of gravity to move the sewage. On Maui, that means on valuable shoreline, as at Kahului. If the plant is inland, as with the Kihei treatment plant, lift stations to pump the sewage up to the plant. If the effluent is to be reused, that's more power to move it around.

By being near the source, package plants require little pumping if at all. Package plants can promise lower costs for the life of a system, Taylor said.

Wilkinson claims an extra advantage for his technology: resale value. If a project outgrows its plant, or if a homeowner moves, he can pick up the plant and move it. There's no leachfield required.

On Maui, sewage sludge is trucked to the Central Maui Landfill, where it is used as an ingredient in compost. Package plants would do the same.

Taylor said he has no plans to experiment with package plants, because Maui's department is too small to have a research and development budget.

But he expects large municipalities, including Honolulu, to do so.

Wilkinson is lobbying for Honolulu to adopt distributed treatment to address Environmental Protection Agency demands that the City & County upgrade its huge Sand Island treatment plant. He claims it could halve the cost, estimated at $2 billion for large-scale technology.

Each development will have somewhat different characteristics, of terrain and type of sewage. Experience gained elsewhere should be useful on Maui.

"We try not to reinvent the wheel," Wilkinson said.

He notes that Maui, with no significant industry, does not have to worry about dealing with heavy metals and other troublesome components of wastewater. Jencks said his project will generate "high quality sewage - if there is such a thing - that will be easy to treat."

Taylor estimates that about 70 percent of the wastewater in the county is handled by his division. The revenue is in the $35 milllion to $40 million range, and in recent years his capital improvement budget has ranged between $20 million to $30 million a year.

That has not been enough to build extensive lines to deliver reclaimed water. In Lahaina, for example, the cost of a first expansion of the R1 delivery system is probably at least $25 million.

The county has been concentrating on replacing old lines, such as the one that skirts Kahului Bay, to avoid potentially disastrous breaks - such as the one that occurred in Waikiki when a broken main line polluted the Ala Wai Canal and the shoreline around Waikiki.

Maui had a smaller but similar situation a few years ago, when sewage had to be directed into lakes at Kaanapali until a line could be repaired.

If sewage were treated locally instead of in large central plants, "it would be a huge advantage not to have to transport it both ways," Taylor said.

Although Jencks would like to have access to the county wastewater treatment system because of the cost, there's no chance he will get it any time soon.

During the hearings on his zoning, Taylor's department had no position about whether the land should be rezoned, but if it were, "we lobbied very strongly that we thought he should build his own plant."

Honua'ula got its zoning and the County Council made building an independent treatment plant a condition.

Taylor says that during the Honua'ula hearings, he spent a lot of effort to explain the intricacies of wastewater, including its implications for power demand, water consumption and the environment.

"I hope it's pretty well understood," he said.

People did speak against the decentralized plant, he acknowledged, but said they should understand that the Wastewater Reclamation Division was speaking only of engineering and upkeep matters. The decision to develop or not develop is someone else's responsibility.

"Just because someone doesn't like a development proposal, that doesn't mean the technology is bad."

Harry Eagar can be reached at heagar@mauinews.com.