From September 1st to September 3rd, 2019, Hurricane Dorian struck the Abaco Islands and the Grand Bahama Island. As a Category 5 storm with sustained winds of up to 185 miles per hour and storm surges of about 20 feet, Hurricane Dorian knocked out critical infrastructure and left some 70,000 people homeless.
After a disaster like this, water becomes the most pressing need. But how do you provide emergency water when the infrastructure is destroyed? We looked into that question on The Outfall podcast as we talked with George Greene IV, president of Charleston-based international humanitarian group Water Mission. We learned about Water Mission’s work providing emergency safe water solutions and the unique and costly challenges to providing clean, safe water to the Bahamian communities hit by Hurricane Dorian.
Hurricane Dorian hit this area of The Bahamas with 185 miles per hour sustained winds, gusts up to 220 miles per hour, 20-foot storm surge, and then also on top of that, 30 inches of rain.
George Greene, President of Water Mission
George explained that Water Mission’s response to the Bahamas was unique because of the way that the area collects and stores water. Many Bahamians collect rainwater for use, but the 20-foot storm surge damaged the collection basins and contaminated the stored water. With no other freshwater sources available on the islands, seawater was the best available supply for emergency water production. Seawater, however, can be the most difficult kind of water to treat, which is where reverse osmosis technology comes into play.
Water Mission is unique in that it does not have its own stock of reverse osmosis systems but rather works with corporate partners to find available systems and parts throughout the country. It then uses its own team of skilled engineers to assemble the systems onsite. At the time of our discussion, George said they had close to 20 reverse osmosis units deployed in the Bahamas. The units range in size from being able to purify a couple of hundred gallons per day to 30,000 gallons per day.
While there are many technical details involved in setting up a reverse osmosis system, cost and energy are major factors. One reverse osmosis unit can cost up to $25,000 and has a high energy requirement. George noted that a 4,000 gallon per day system requires a 20-kilowatt diesel generator, whereas one of their freshwater treatment systems only needs a six-kilowatt generator. When saltwater needs to be purified, a reverse osmosis unit requires three times the power and produces less than half the water.
