3/6/2009 12:08:00 PM Part II of II Making saltwater drinkable could leave a sour legacy Desalination might ease water shortages but cause irreparable, long-term damage
Rowan Hallett Guest columnist
Sometimes you can't see the ocean on account of the salt. Sustainability: the environmental buzzword for the 21st century, and Bermuda's Government is determined to prove that this time, they aren't simply paying lip service.
To many, the planned Tynes Bay reverse osmosis facility appears to be a viable solution to the problem of water shortages. This plant will convert saltwater to drinkable freshwater by compressing it through a semi-permeable membrane, which traps the salt while allowing the fresh water to pass through.
But we need to look more closely at what it being proposed.
It is difficult to believe that anyone could stand on one of the South Shore beaches, peer across the ocean stretching to the horizon and see it as a yet-untapped resevoir. Are we about to undermine a vast and largely unexplored ecosystem?
The planned development of the Tynes Bay desalination facility suggets that the pragmatic resource potential of the ocean outweighs any other inherent value. If this comes as a shock, it shouldn't. The new reverse osmosis plant will represent yet another symptom of the plague of consumerism that now pervades our island.
Each day, 600,000 gallons of water will be removed from the ocean to supply the country's demand. Furthermore, the facility will have the capacity to expand production to 1.2 million gallons per day.
The notion that we can rely on the ocean to subsidise our water production is based on a deeply flawed premise that these natural resources are unlimited and renewable. Rather than solve the problem of water shortage, the desalination plant will only exacerbate the underlying cultural problem - rampant consumerism - that is causing it.
The Department of Works and Engineering has been reluctant to detail the process to be used in the new facility. Typically, approximately half of the intake of seawater becomes freshwater, while the remaining salt-concentrate by-product is recycled back into the ocean. As a result, the run-off contains approximately twice the salt of natural seawater. Common sense and a moment of reflection should tell us that such a system cannot possibly be sustainable.
The sad fact is, we've lost touch with nature and we don't realise that the consequences of these choices will stay with us in the long term. We are essentially polluting our oceans with their own by-product. Increases in the salt concentration could turn our underwater nirvana into the new Dead Sea.
While it may be entertaining for locals to watch our summer tourists bobbing about like sunburned beach-balls on our newly-buoyant waters, corals and other marine life will not be able to withstand the toxic levels of salt. The delicate ecosystems built on this foundation will collapse - taking our tourism industry with them.
Environmental catastrophe
If this doomsday prophecy seems too difficult to bear, one tiny consolation is that it probably won't happen in our lifetimes. But a generation as yet unborn might never know what it's like to snorkel at Church Bay or watch humpback whales frolic on a chilly March morning. As long as we continue to perceive nature as a standing resource for our exploitation, environmental catastrophe is inevitable.
So, what can we do? The best way to reduce our dependence on the desalination plant is to use alternate methods of water production, and there are plenty available to us.
Dehumidifiers that collect the water extracted from the air are readily available on the island, and can collect 6 to 10 gallons of drinkable water at a time, while also cutting home cooling costs.
National water catches island-wide have not been adequately maintained so the water collected is no longer fit to drink. Perhaps if the Government had invested some of the $10 million earmarked for the desalination plant to restore these catches, Bermuda wouldn't need the plant. The prisons' labour force could serve the island by working on these catches and also benefit from training in water treatment.
Why not look at a progressive way of charging for excess water consusmption? We meter our electricity consumption, so why not our water? We could figure out reasonable montly averages and those consumers who use more than most would have to pay. Few things curb wastefulness quicker than the threat of a financial penalty.
Government could implement a luxury tax on high water-consumption products, such as swimming pools, in order to re-establish the boundaries of luxury and necessity. A positive reinforcement system, rewarding companies and establishments that have water-conservation practices in place, is another option.
Maybe putting a price tag on our consumer-driven lifestyles could be the first step in motivating us to rethink how we perceive the natural world.
We shouldn't blame ourselves for losing sight of the ocean on account of the water, but we do have to hold ourselves accountable for the consequences of the choices we make today. It seems we need to choose between short-term fixes and more difficult, sutainable solutions.
Posted: Thursday, March 19, 2009
Comment by:
David Chapman
The author's main theme of sustainability is laudable, especially in consideration of his call for more conservation of water use and the upgrading of present low carbon water harvesting solutions such as water catchment.
However, his rally against reverse osmosis (RO) is not scientifically valid. The input of hyper-saline water (salty byproduct from RO) is in no way a detriment to the incredibly huge volume of sea water contained in our oceans. Indeed, this is just a drop in the proverbial bucket and the sun's evaporative power causes more concentration of salinity to the ocean then man could ever think to.
The real negative to reverse osmosis comes in the form of the high energy cost required to carry out the process. The Tyne's Bay Incinerator has an inherent ability to desalinate water thermally through distillation which it does and the water produced is used in the plant's own processes. However, the new RO plant requires electricity to run the pumps. If this electricity is being sourced from the Waste to Energy plant (incinerator) then it is "semi-sustainable" but if it is reliant on grid-sourced electricity then it is not. Much environmental impact studies into this introduction of salty water into local ecosystems have been conducted globally.
The author is also obviously not aware of the RO use of major beverage companies like Barrit's which take their water from the underground freshwater aquifer - this is more of a valid threat to water management and sustainability then the Government desalination plant. Luckily Bermuda has an extremely well managed hydrology through the Government Department of Environmental Protection that prevents over harvesting, pollution and provides constant volume and water quality monitoring. In this vein, the author also doesn't make the connection between the over harvesting of Bermuda's aquifer's from extraction and how desalination is an important positive that will help to conserve the fragile and limited underground fresh water lens.
The author also calls for use of dehumidifiers - 6 - 10 gallons. He is obviously not aware of the volumes required on a daily basis by the average home or building in Bermuda. These dehumidifiers would also have a high energy cost if we are talking about the size needed to make any real contribution unless they are run on renewable energy such as solar. There are some commercial untested concepts for the purfication of water through natural condensation using cold seawater running through pipes as the condenser, however these would need to be absolutely enormous to provide us with our water needs.
As to the "national" water catchment- what national water catchchments? Most of the large water catchments seen around Bermuda are privately owned by golf courses and the ones that are owned by government are maintained meticulously.
The author states "but a generation as yet unborn might never know what it's like to snorkel at Church Bay or watch humpback whales frolic on a chilly March morning" - is he trying to suggest that desalination would cause this? I challenge him to show me a realistic scenario for how this would happen based on desalination and the input of hyper saline water.
The author needs to do a considerable amount more research before making such ludicrous and unscientifically sound statements. Sounds like "scare-mongering" to me...
David Chapman
Environmental Scientist
Posted: Sunday, March 08, 2009
Comment by:
Tom
The end portion of this article is an excellent way for government to fix SOME of the issues with water consumption. Bermuda needs to BETTER educate Bermudians on water consumption. However, Bermuda should also implement reverse osmosis facility, as this is a viable source of fresh water. Other countries use this method and it has been proven to be successful (if done right)! This would create additional jobs for Bermudians and show that Bermuda can adapt with the times. Or what if Bermuda implements a faculty that purifies our own wastewater? It has been done and successful for other countries, why not ours? This would allow us to reduce our environmental footprint by reducing our waste output. We need to evolve with technology or we will be left behind!
