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White Water to Blue Water Partnership Conference March 22-26 2004, Miami, FL
Global Coral Reef Alliance Comments On: 1) Water Quality
Standards, Monitoring, and Sewage Treatment
Water Quality Standards, Monitoring, and Sewage Treatment Comments at Bonaire sewage system and treatment plant and Marina waste management at Elizabeth Harbor, Bahamas presentations at Sewage Session Coral reefs are the most nutrient-sensitive of all marine ecosystems and are killed and overgrown by weedy algae at nutrient levels that would not affect any other ecosystem. As a result they require the most stringent nutrient limits and the highest level of waste treatment of any ecosystem. The Bonaire project is very important because they are trying to keep their reefs in good condition by nipping pollution in the bud at the very first signs, while most other parts of the Caribbean waited until it was too late. There is another important part of the Bonaire project. They are planning to use state of the art equipment to map the distribution of nutrients so that they can identify every single nutrient source and track them back to their origin. Coastal zone management is still in the dark ages because no coastal zone manager knows how many nutrients are entering their coastal zone or where they are coming from, except for the most obvious sewage outfalls. As a result they cannot properly devise policies to control the nutrient inputs. In recent years monitoring equipment has been developed that is affordable, portable, and capable of being used to continuously and instantaneously map nutrients and related water quality parameters. This allows every source of nutrients to be found, their seasonal variations to be measured, and the effectiveness of management policies to reduce them to be determined. Use of such methods will place coastal zone management on a scientific basis at last. If Bonaire gets this program going, they may be the first place anywhere to do so. Only recently have we come to understand just what the critical nutrient limits are for coral reefs, their acceptable water quality standards. These are based on measurements of nutrients with regard to the abundance of algae and corals, and measurements of the effects of nutrients on the growth of algae. The critical limits are very low, only 1 micromole per liter of available nitrogen as ammonium plus nitrate, or 0.014 parts per million of available nitrogen. For phosphorus they are only 0.1 micromole per liter of phosphorus as orthophosphate plus dissolved organic phosphorus, or 0.003 parts per million of available phosphorus. Because nutrients can be rapidly taken up by algae, the nutrient levels can fall to low levels in the water even in areas that have excessive nutrient input. This is because nutrients are tied up in the biomass, and can be rapidly released again when it decomposes. Nutrients that have been taken up by phytoplankton and turn the water green can be measured by the amount of chlorophyll in the water. Therefore we also recommend a critical acceptable limit for chlorophyll A as 0.5 parts per billion (or milligrams per cubic meter). Water quality standards based on cold-water ecosystems are much higher, and inappropriate for coral reefs, as are those based on human health, since humans and cold-water ecosystems can tolerate nutrient levels hundreds of times higher than corals can. There is a complete consensus on these limits by all people who have directly measured nutrients in coral reefs and their effect on algae. Unfortunately, they have been controversial because there has been a large cottage industry of people who have NOT measured nutrients and tried to explain algae by other factors. This has led to bad science and worse policy by distracting attention from the need to keep nutrients out of the water. At the recent UN Expert Meeting on Waste Management in Small Island Developing States (http://www.sidsnet.org/workshop/experts_meetings.html), we called for ZERO human caused nutrient inputs to the coastal zone. While this may seem an unreachable goal because of natural backgrounds and variability, it is what we must aim for if we wish to protect our coral reefs from pollution. With regard to the proposal for deep well injection disposal of sewage in the Exuma Islands in the Bahamas, it sounds as though they have hired consultants from Florida, where "out of sight out of mind" seems to be the motto. The sewage that is pumped into the ground in Florida emerges from underground rocks into the coastal zone, where it is killing the reefs. All this does is to delay the problem and kill corals from the offshore side instead of from the land side. Ironically, the Exuma Islands are the site of a very important recently published study by Brian Lapointe that conclusively shows that excess nutrients are the cause of excessive algae, not lack of animals that eat them. Long-term protection of these reefs would be served by applying the work that has been done locally. It is much better to treat the sewage on land, recycle the nutrients, and make the land green by growing more plants, preventing the nutrients from getting into the sea and killing corals. Even if you don't have space to grow a cash crop, you can water lawns, ornamental vegetation, or even wild vegetation whose plants are starving from lack of nutrients. In the UN Expert Meeting, Hugh Sealy from Barbados presented a very important paper. Garbage decomposition is limited by lack of water and nutrients. He shows how sewage effluents can be applied to garbage to increase the rate of decomposition and minimizing pollution, by lining the bottom to prevent contamination of groundwater, while maximizing energy production by lining the top to trap the methane produced. By combining solid and liquid waste treatment, instead of doing so separately, many environmental problems can be solved, and renewable energy generated. Larger Impacts of Cruise Ships on Coral Reefs Comments at Session on Charting a Course: An International Congress for Coral Reef Protection from Ship-based Tourism I am Tom Goreau of the Global Coral Reef Alliance. I have just finished a review of measures to protect corals from nutrients for the UN Expert Meeting on Waste Management in Small Island Developing States (http://www.globalcoral.org/WASTE NUTRIENTS IMPACTS ON COASTAL CORAL REEFS.pdf). We strongly support all efforts to reduce nutrients that are damaging coral reefs, and welcome the efforts of the cruise ship industry to install advanced wastewater treatment facilities to treat cruise ship wastes. But to be effective all nutrient sources affecting reefs must be reduced, including those of local populations. If they don't also benefit from sewage treatment there will not be lasting results. I have recently looked at the reefs near the cruise ship terminal at Cozumel. I could find no impact from the cruise ships on the downstream reef. I was very surprised but I know the Caribbean algae well and there was no sign of algae increases. So I'm convinced that they are not discharging cruise ship wastes in port and that these operations can be done in a clean way, and are at Cozumel. That's the good news. The bad news is that if you go a few miles down to the coast to the dolphin attractions, a kilometer of reef has been overgrown by algae. (http://www.globalcoral.org/Dolphin enclosures and algae distributions at Chankanaab, Co.htm). All around the dolphin area you can see dense slimy mats of the same kind of bacteria that you can see right offshore from here if you dive on the Miami sewage outfall pipes (http://www.globalcoral.org/What Should the Policy of the Municipality of Cozumel.htm) It seems incredible that around 20 dolphins can be polluting more coral reef than thousands of cruise ship passengers a day, but that is what we see. The largest market of visitors to the dolphin attractions is cruise ship passengers, who are constantly barraged with videos, brochures, and posters to see or swim with dolphins. So these impacts are directly related to the cruise ship business. The political aspect of this problem is that dolphin attractions are so profitable that every Caribbean cruise ship destination is trying to develop them. Place after place now says that they can't compete if they don't have dolphins too. All the wild dolphins in the Caribbean are now under threat of capture for tourist attractions, largely driven by the expansion of the cruise ship business. This is a serious local threat to coral reefs near these proposed attractions as well as to the wild dolphin populations. I just want to bring to your attention that there are real environmental impacts that are indirectly caused by the cruise ship business and that you need to deal with all the pollution impacts while you try to clean up the pollution directly caused by ship wastes. If you don't deal with this the cruise ship passengers disembarking at the piers will soon start to be met by local animal rights activists carrying signs saying "Swim with dolphins, kill the reef".
Effective Community Based Coral Reef Restoration Comments at Restoring reefs and rural livelihoods/Coral Gardens Initiative presentation at Session on Community Participation in Integrated Watershed Management GCRA strongly supports all efforts to restore coral reef restoration, but we believe it is very important to use methods that are effective. Before the Coral Gardens Initiative in Fiji began, we warned them that the methods being used would only work if the waters were very clean, and that the transplanted corals would die if the water became too hot, muddy, or polluted. Our colleagues in Fiji say that these corals all died when the waters became very hot in 2002, as we had predicted. The loss of coral reefs is rapidly escalating worldwide, and large-scale restoration of coral reefs and fisheries is crucial and far more urgent than is recognized. However, it is essential to focus on methods that really work, especially in the Caribbean where the effects of pollution and global warming are more concentrated than in the Indo-Pacific. We have developed methods that allow us to keep corals alive under conditions of high temperatures, pollution, and sediments that would normally kill them, and to restore coral reefs and fisheries where they cannot recover naturally. We need to use methods that really work, in settings where there is long-term community commitment to them. GCRA is prepared to work with all groups that are seriously committed to restoring their coral reefs. |
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