The gardens of a 16th-century Italian villa, damaged by hard water and bacterial pollution, recently were restored to a sparkling grandeur through an ambitious water treatment project.

Touted as a spectacle to rival Versailles, the estate of the Villa d'Este in the town of Tivoli (about 25 miles northwest of Rome) serves as backdrop for 50 fountains, 100 basins and 60 reflecting pools. All of this water is accentuated by waterfalls, lilies, rhododendrons and other floral displays and was all designed as a sort of paradise on earth by 16th-century architect Pirro Ligorio for Cardinal Ippolito d'Este.

But every earthly paradise has flaws, even a paradise owned by a cardinal, and Villa d'Este has been no exception. Even in Renaissance times, the water of the Anio River (which fed the pools and fountains) was "hard," and there was no filtration or purification system to counter its effects on the villa's waterworks. When the Italian government took over the estate in 1918, the property, and especially its fountain sculptures, was badly in need of restoration.

Work was done to restore the villa, but the problem stemming from the increasingly polluted waters of the Anio River was not addressed until the mid-1920s, when a new hydroelectric plant and reservoir were built nearby. The latter then served as the source of water for Villa d'Este.

But the pollution continued as the population grew and the economy of the Lazio region shifted from agricultural to industrial. In 1989, the villa was closed in response to a request from the an environmental group, headed at the time by Giovanni Hermanin.

"Analyses showed the presence of bacteria and fecal matter 100 times higher than the legal maximum," recalls Hermanin, "and I felt obliged to call this to the attention of the authorities. The villa and gardens had been in poor condition for some time, and a number of measures were taken right away: some fountains were closed, others operated with reduced water and others were surrounded by iron fences. Perhaps the biggest loss that was suffered was the closing of the Promenade of 100 Fountains; that had really given visitors the sense of an aquatic ambience."

The negative publicity and the reduced water spectacle had a dramatic effect on tourism in Tivoli and the surrounding area. Over the next decade, Villa d'Este lost up to 400,000 visitors annually and considerable indirect income from unrealized tourism.

Hermanin became head of environmental affairs for Lazio in 1995 and decided at that point to do something positive to improve the situation. He asked Sergio Lucianetti, an engineer based in Rome, to develop a solution that would be energy and cost-efficient as well as effective. "There were no unusual technical problems," says Lucianetti, "but we had three major issues to address. First, we needed to remove objectionable bacteria from the water. That meant cleaning the reservoir from which the water for the villa is taken because the community of Tivoli had been depositing its waste there for decades before we were able to intervene."

"Water is the symbol of the state of health of an environment," notes Hermanin, For that reason his department is spending $70 million (U.S.) on a project to address the problem of the polluted Anio River. Dozens of ITT Flygt pumps already are operating in water purification stations in many small communities throughout the region. About 30 percent of the project is completed; the rest will be completed by the end of next year.

A second problem was the mud that gradually was blocking the hydraulic flow throughout the villa's fountains and waterways. Every year the complex had to be closed for at least two weeks to clean up about 130 cubic yards of solids and mud that had accumulated. A third problem was the hard water and accumulation of calcium that had long marred and deformed the sculptures in the fountains.

Lucianetti's solution to the bacterial pollution was to expose the water to ultraviolet light from medium-pressure lamps. Exposure to UV modifies the DNA of bacteria, making reproduction impossible. This choice was more energy-efficient and less bulky than the more traditional solution of low-pressure UV lamps.

The blockage of hydraulic flows was eliminated by a series of five self-cleaning filters able to handle water flows of 130 gal./sec. For this part of the project, ITT Flygt's submersible pumps played a key role in bringing the water to the filters with minimal environmental impact. This was especially important in an environment as aesthetically sensitive as that of Villa d'Este.

Calcium deposits were handled by subjecting the water to high-frequency signals that transform the calcium bicarbonate into aragonite rombica. The latter is not only non-damaging, but it actually has a positive effect: It automatically cleans the sculptures, returning them to their original color. "In fact," admits Lucianetti, "we have set up a committee that will tell us when this has gone far enough, so we can reduce the self-cleaning effect."

The fountains of the historic site were re-inaugurated in the presence of Carlo Ciampi, president of Italy, and a host of dignitaries. The economic impact was immediate. Attendance at Villa d'Este increased at such a rate that payback for the project will be achieved within 18 months. "In the first month alone, there was a 200 million Lira ($100,000 U.S.) increase in ticket sales compared to the previous year," notes Hermanin, and adds with a smile, "I have become a pretty popular guy in Tivoli because of this."