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Drink up: A reclaim to fame?

Since St. Petersburg pioneered the use of residential reclaimed water in 1976, Florida has solved complex technical dilemmas, built miles of pipelines and hundreds of treatment plants, started using reclaimed water in agriculture, and developed what are arguably the nation's most comprehensive and well-thought-out state regulations on reuse. But sometimes, people are still confused: Can we use it on our gardens? (Yes and no). And the question remains: Will we one day be drinking reclaimed water? (Yes.)

Florida is about midway on the Reclaimed Water Use continuum. It began in the late '60s with the It Can't Be Done stage, and ends When We Drink the Stuff _ which is very definitely on the drawing boards. In the meantime, use of reclaimed water has become as familiar as microwave cooking. Some 14 years after St. Petersburg started using treated wastewater on golf courses, pastures and lawns in selected neighborhoods, communities all over the state and the nation have signed onto the idea.

In Florida, 200 water treatment plants produce about 1-billion gallons of reusable, reclaimed water a day, according to the state Department of Environmental Regulation (DER). And reuse has jumped from 206-million gallons a day in 1986 to 320-million gallons a day in 1990, one third of the total amount available.

"That is a significant figure," says David York, reuse coordinator for DER. "We'd like it to be larger, and it's going to get larger, but it's not too shabby. We've come a long way pretty quickly."

On a daily average, about one-third of a potential amount of 280-million gallons of treated wastewater in 16 southwest Florida counties is reused, according to the Southwest Florida Water Management District (Swiftmud).

St. Petersburg, on an annual average, reuses nearly half its wastewater, 19-million gallons a day, says David Shulmister, manager of wastewater treatment in the city. Reuse exceeds 90 percent during peak water use times.

According to Swiftmud, there are seven reuse projects being financed this year in Hernando, Pinellas, Manatee, and Sarasota counties. New or expanded systems are in the works in St. Petersburg, Spring Hill, Palmetto, Venice, and Sarasota.

Clearwater is expanding its system. Hillsborough County has plans to increase its modest reuse of 6- or 7-million gallons daily, targeting in time residential, industrial and agricultural users. Pasco County uses reclaimed water on golf courses, Citrus on hayfields.

"Reuse is coming more into the fore-

front all the time," says James Crook, principal engineer at Camp, Dresser & McKee, an engineering consulting firm in Clearwater that designs reclaimed water pipeline systems. "As we have droughts and water shortages, people are realizing it's a resource."

Yes, but is it safe?

Working out the bugs

In St. Petersburg, there resides a woman known as the expert on viruses. Now retired, Flora Mae Wellings was director of the state's Epidemiology Research Center in Tampa, and worked with the city of St. Petersburg beginning in 1971, when it first examined water reuse. She sought to identify how many viruses domestic wastewater harbored, and to figure out how the viruses could be eliminated or neutralized.

That was back in the It Can't Be Done stage: Viruses? Where?

"When I first started," Wellings says, "they laughed at me. In fact, Dale Twachtmann said one time he enjoyed listening to me, but he didn't believe a word I said. And now he's head of environmental regulation. That was the attitude of engineers at the time. If they can't measure it or see it, it doesn't exist."

As it turned out, Wellings learned, there are at least 50 viruses that exist in the water "that can cause anything from a runny nose to encephalitis."

In the mid-1980s Wellings conducted studies that showed that the wastewater coming out of some Hillsborough County treatment plants contained viruses. As a result, filters were added to the plants. The filters are part of a process Wellings helped design to remove or inactivate viruses in wastewater today.

It is a multistep process. First, wastewater is cleared of large debris. Then it goes to a settling tank where heavier material settles to the bottom. The water sits in another, aerated basin that promotes certain microorganic growth and activity, which further cleanses the water. The water goes through a coal-sand filter. Finally, it is disinfected with chlorine.

The state requires an elaborate monitoring and testing system of the treatment plants and the water quality.

The final product, reclaimed water, has been used for years to sprinkle lawns, pastures, playgrounds, golf courses. There was no problem, no controversy.

But viruses have a way of lingering, even in debates. In 1989, the Department of Environmental Regulation proposed using reclaimed water directly on all edible crops. Suddenly, people had visions of sewage water on their salads.

The state Department of Health and Rehabilitative Services objected to the use of reclaimed water directly on vegetables that would be eaten raw _ such as lettuce, strawberries, tomatoes. Florida's tropical climate, HRS claimed, is kind to viruses, and allows them to "persist in a viable state for prolonged periods of time" _ presumably until they reached, via a piece of lettuce, your salad bowl.

Basically, says Wellings, "There are certain viruses we can't isolate," which poses a potential problem if reclaimed water is used on these vegetables. "That's the reason they don't want us to drink it, either."

Crook, who helped California write its reclaimed water regulations before coming to Florida, agrees. "There are still some answered questions about trace organic constituents, which may cause long-term health effects. Almost anything that goes down a toilet may end up in waste water. Why take the risk?"

But many say the alarm was completely unwarranted.

"Reclaimed water, in an appropriately designed, properly operated treatment plant, is going to be virus-free," says Shulmister in St. Petersburg. "And further more, you're not using reclaimed water for drinking." But, he claims that even for drinking, it is "virus-free."

The Department of Environmental Regulation compromised, even though, DER's York says, there is "no technical basis" for prohibiting direct contact of reclaimed water on certain vegetables. It was instead allowed to be used directly on citrus fruits and tobacco, and other edible crops that will be "peeled, skinned, cooked or thermally processed." Vegetables such as tomatoes and lettuce cannot be directly sprayed with reclaimed water. Furrow or drip irrigation and other non-contact irrigation is allowed, however.

These rules apply as much to back yard gardens as they do to farms. If your sprinkling system uses reclaimed water and hits your garden full of lettuce, tomatoes or other such raw-eaten vegetables, you need to redirect the spray.

Obviously, this is difficult to enforce, and widespread availability of the water to some degree reinforces the confidence experts feel about its safety.

"We recognize that when we make it available to some 6,000 residential customers," York says, "we are not going to have any direct control over what they're actually doing with it. There are going to be some people who are going to irrigate their tomatoes with reclaimed water."

The water poses no health hazard if, for example, your sprinklers accidentally spray you, if you roll on grass recently sprinkled with reclaimed water, or even if you gulp some inadvertently.

Reclaimed water is now widely used by the citrus industry. But few vegetables you buy in the store are raised with reclaimed water _ unless the vegetables are from California, which allows direct contact of reclaimed water on all crops.

This will change in time in Florida, as new systems gradually bring reclaimed water into Florida's farm fields.

Drinking water is next

Meanwhile, two major demonstration projects, in Tampa and in Denver, are focused on the possibility of using reclaimed water for drinking water.

The city of Tampa, working with West Coast Regional Water Supply Authority, has been studying for the past few years ways to further treat already purified reclaimed water and then add it to the raw drinking water supply _ the Hillsborough River.

The aim, says David Pickard, wastewater plant administrator for the city of Tampa, "would be to supplement the raw water supplies during drought conditions." This already is being done in some other areas, he says. The water drawn from the river for drinking is, of course, treated.

The Tampa project also is conducting extensive health tests, which should conclude in the next two years.

Denver's demonstration project, which will conclude in 1991, has for 20 years studied the technical and financial feasibility of using specially treated reclaimed wastewater for drinking.

"All tests indicate this water is as good or better than any now consumed routinely, including all purified bottled waters," stated William C. Lauer, Reuse Project Manager at the Denver Water Department, in a recent news release.

Denver, he said, soon will be able to use such water "when it is needed," although, "some have speculated that the public will not accept this supply. However, opinion surveys have indicated general acceptance if the need is demonstrated and the quality is assured."

Although reclaimed drinking water will not receive "wide application," Lauer says, technology learned during the project will be applicable in issues such as contaminated groundwater, toxic substance removal, hazardous waste clean-up, health effects, and water treatment in general.

Get out the water goblets. That, essentially, says Pickard, is the future of reclaimed water.

"We're not taking it lightly," Pickard says of the efforts to make reclaimed drinking water a reality. "We're all gonna be drinking the water. Someday it will become the next viable source _ maybe the last viable source _ of water."

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