The fire hydrants on Toas Island have been nothing more than dry street decorations for six decades. Today, they're flowing and residents are drinking fresh water again from the lake that surrounds them.
Toas Island is located in the middle of one of the world's largest fresh water lakes. Sadly, for the last 60 years, all that water might as well have been aqua-colored ink. In pursuit of petroleum under the lake, the lake has been channeled to the sea for freight traffic that, over time, has allowed for seawater to intrude, making the lake's waters unsuitable for drinking, cooking or other everyday needs.
Deteriorating Supply
Island residents were stranded, dependent on a corroded water pipeline from the mainland that only ran twice a week for four hours, and a rusted, undependable barge that would make two trips a week for water - when it wasn't broken down. “To the people on the island, water was like gold,” says Mainor Vega, WET's Latin America business manager.Thanks to WET, those problems are in the past and Toas Island is no longer dry. This past year, the Florida-based company completed the installation of a reverse osmosis desalinization system that is pumping nearly 400,000 gallons of water to Toas residents each day. For many islanders, the presence of fresh water feels like a miracle, but it's more a matter of smart engineering and hard work.
WET produces a variety of membrane-based water purification systems to an array of markets including commercial/industrial, municipal and seawater desalination for process, potable, high purity and wastewater applications.
Unique Application
WET has sold thousands of membrane-based water purification systems over the past three decades. Each application is unique and WET engineers treat each application as a stand-alone design. For example, in water desalination, the company uses ocean engineers who are trained extensively in water chemistry, fluid dynamics, corrosion and other related sciences, which are necessary to successfully design, build and apply proper water desalination techniques.One of the key design features of the desalination system for Toas Island was building a system that was flexible in its operating parameters. Depending on tide swings and seasonal shifts, the salt levels in this area of Lake Maracaibo change drastically - ranging from 8,000 parts-per-million all the way up to sea water levels of 32,000 ppm. The higher the salinity level, the more pressure is needed to push water through the reverse osmosis membranes.
This particular system was designed so operators could take constant measurements and make the appropriate pressure adjustments.
2,500 Households
The World Health Organization defines fresh water as having salinity levels of 1,000 ppm. In the United States, drinking water needs to be below 500 ppm. WET's seawater reverse osmosis systems installed in Toas Island provide water with salinity levels less than 100 ppm.After it was designed, the system had to be transported by boat and truck to the remote island. ITT Industries' Goulds pumps are used to transport the water from the lake to the clarification tanks, the multimedia filtration system and finally to the reverse osmosis systems. The water from the desalinization plant is sent through more than six miles of piping to a 390,000-gallon storage tank located at the highest point of the island. Gravity does the rest, supplying fresh water to the 2,500 households on the island.
Vega spent nearly a month on the island, working 15-hour days to oversee the installation of the system and to train the operators. He admits that some days were a struggle, dealing with tricky political issues and problems like a lack of dependable power sources. But he'll never forget how the treatment system changed the island on a very human level. “The first day with water, children were outside my window at 2 a.m., playing in the mud because they couldn't believe there was enough extra water to even create mud. The smiles were incredible and very real,” he remembers.
The water is transforming the island on a larger scale, too. “When we first got to the island, none of the fire hydrants operated. Now, they are thinking about putting up small hotels and trying to build tourism,” says Vega. “This is one of the poorest sections of Venezuela, but with water, they now have hope and a future.”
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