WET Unit Provides Water to Dry Island
The fire hydrants on Toas Island have been nothing more than dry street decorations for six decades.
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 freshwater again from the lake that surrounds them thank to ITT Aquious’ Water Equipment Technologies (WET) desalinization system.
Toas Island in Venezuela is in the middle of Lake Maracaibo, once one of the world’s largest freshwater 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 allowed for seawater to intrude, making the lake’s waters unsuitable for drinking, cooking or other everyday needs.
Deteriorating Water 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 made 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 the ITT unit, those problems are in the past and Toas Island is no longer dry. In 2003, the company completed the installation of a reverse osmosis (RO) desalinization system that pumps 1.5 million liters of water to Toas residents each day. For many islanders, the presence of freshwater feels like a miracle, but it’s more a matter of smart engineering and hard work by the WET team. Founded in 1975, WET produces a variety of high technology, membrane-based water purification systems to an array of markets including commercial/industrial, municipal and sea water desalination for process, potable, high purity and wastewater applications.
“A lot of other companies are like robots, selling out of catalogs, but we knew this job demanded a system engineered for the difficult site conditions,” says Vega.
Pure Water for All
One of the key design features of the desalination system for Toas Island was building a system flexible in its operating parameters. Depending on tide swings and seasonal shifts, salt levels in this area of Lake Maracaibo change drastically – ranging from 8,000 parts-per-million up to seawater levels of 32,000 ppm. The higher the salinity, the more pressure needed to push water through the RO membranes.
With water chemistry and fluid dynamics in mind, WET’s system allows operators to take constant measurements and make appropriate pressure and other adjustments. The World Health Organization defines freshwater as having salinity levels of 1,000 ppm. In the USA, drinking water needs to be below 500 ppm. WET’s seawater RO systems installed in Toas Island provide water with salinity levels under 100 ppm.
After being designed, the system had to be transported by boat and truck to the remote island. ITT Goulds pumps are used to move the water from the lake to clarification tanks, multimedia filtration and RO systems. Water from the desalination plant is sent through over 10km of piping to a 1.5 million liter storage tank at the island’s highest point. Gravity does the rest, supplying freshwater to the 2,500 households on the island.
Vega spent nearly a month on the island, working 15-hour days to oversee the system’s installation and train 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 WET’s 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. They couldn’t believe there was extra water to even create mud. The smiles were incredible and very real,” he recalls.
Now, not only do fire hydrants work again, but the island is considering small hotels to build tourism. One of the poorest sections of Venezuela, the island now has hope and a future with water.
ITT Water Equipment Technologies is based in West Palm Beach, Florida, USA.