Water - A Scarce Resource in Tobago?
Tobago’s forests, rivers and streams are our source of precious water and we must protect them.
Why is it in on an island blessed with abundant rainfall we are cursed with a sporadic and unreliable water supply? Why is it that our water is often murky with silt?
Water is one of the Earth’s most precious natural resources, upon which all life depends. Unfortunately in Tobago we are not able to manage this resource adequately to provide for the needs of the population, and we are continuing on a course of unsustainable management of our water resources.
Unsustainable use of water
Water is a renewable resource within the limits of the hydrological cycle, in which seawater evaporates and falls over land as precipitation. The renewable supply of water is the surface water in rivers and streams and the groundwater stored in underground aquifers. Although almost three quarters of the Earth’s surface is water, less than one percent is freshwater that humans can potentially access in rivers, lakes and groundwater.
Water can, in principle, be reused many times. However, our ability to reuse water can be limited by polluting surface and underground sources, watershed degradation caused by deforestation, pumping water from underground aquifers faster than they can be recharged, or diverting so much water from wetlands or rivers that freshwater ecosystems fail. These unsustainable practices are unfortunately commonplace, and increasing, in Tobago.
WASA report links deforestation with decreasing water supply and quality
Vegetation cover is essential to the proper functioning of a watershed, yet rampant deforestation and forest degradation continues in Tobago. This is caused by poor land use decisions detrimental to watershed integrity. Pressures include expanding human settlements, land clearing for agriculture, poor agricultural practices on steep slopes, and indiscriminate burning.
For example, a 1994 WASA report on the watershed protection programme for the Courland Catchment notes the degradation of this vital watershed that services the whole west and south coasts of Tobago. It reports a decline in "good" vegetation cover by 20% from 1987-1994 and a 14% increase in "over-exploited" land (as indicated by aerial photographs).
The same report noted that this watershed degradation was responsible for over sixty thousand cubic metres of water being lost from the Courland system from 1969 to 1992, representing an increase in runoff of 13.8%. A 42% decrease in dry season flow over this period was also documented. All this means less water available for Tobagonians.
Poor water quality is also a problem in Tobago. Turbidity in the water is caused by increasing amounts of soil running off the surfaces cleared of binding vegetation. WASA estimated that over half a million TT per year is needed for treatments to reduce this turbidity at Courland. In addition, turbidity was also identified as responsible for decreased supplies of an estimated $319,000 cubic metres/year at Courland and 371,400 cubic metres/year at Craighall.
Towards a sustainable water supply in Tobago
Tobago has the distinctive honour of having the first forest reserve in the world declared specifically to protect a watershed. The Main Ridge of Tobago was proclaimed in 1776 "for the purpose of attracting frequent showers of rain upon which the fertility of lands in these climates doth entirely depend".
Why have we forgotten this basic principle? Inter-American Water Day was celebrated on Saturday 7th October, but not a peep about this was heard in Tobago. Are we taking water resource management seriously? Why are we complacent about the erratic and dirty water supply? Tobagonians must call for their basic human right of access to a clean and reliable water supply.
The improvement works scheduled for our major waterworks are long overdue, and must be coupled with institutional and policy reforms that improve water resources management and protect watersheds. More efficient use of water needs to be promoted, and the various causes of water pollution addressed. There must be commitment to longer-term visions for Tobago's development that recognise that continued deforestation of our watersheds for short-term economic gains is unsustainable and will only lead to social, economic and environmental problems in the present and into the future.
Unfortunately limited water and unsustainable use of water is increasingly a global problem. The United Nations estimates that today one third of the world’s population does not have an adequate water supply. Next week’s article will continue to discuss this problem and some of the possible solutions. - Nicole Leotaud, Education Coordinator of Environment TOBAGO - 9th October 2000
Part II - Water A Global Crisis
The poor quality and irregular water supply in Tobago was examined in last week’s article. The current water supply in Tobago cannot even meet current demands; far less satisfy needs of the rapidly expanding tourism sector.
But this is not just a local problem. The World Resources Institute predicts, "The world's thirst for water is likely to become one of the most pressing resource issues of the 21st Century". Global water consumption rose six fold between 1900 and 1995, which is more than double the rate of population growth. Moreover, this demand continues to grow rapidly as agricultural, industrial, and domestic demand increases.
One third of world's population faces water shortages.
A 1997 United Nations (UN) assessment of freshwater resources found that one third of the world's population lives in countries experiencing moderate to high water stress and that this could rise to two thirds by 2025.
The UN assessment also makes clear that the global water situation will get considerably worse over the next 30 years as the human population continues to grow. The study found that from 1940 to 1990, withdrawals of fresh water from rivers, lakes, reservoirs, underground aquifers, and other sources increased by more than a factor of four.
Increasing demands are being made by every sector. Industrial water use, for example, is predicted to double by 2025 if current growth trends persist. Water use in agriculture is also expected to increase as world food demand rises. Agriculture already accounts for about 70% of water consumption worldwide and the UN projects the amount of water used in irrigation may double by 2025.
The result has been increased pressure on freshwater resources in most regions of the world and a lack of adequate supplies in some localities.
Critical water shortages could hamper sustainable development.
Water experts and international institutions warn that water shortages could become critical in some regions. In the absence of significant changes in policy and far more effective management of water resources, this could pose serious long-term obstacles to sustainable development in many countries.
In some areas of the world, water withdrawals are so high relative to supply that surface water supplies in lakes and rivers are literally shrinking and groundwater reserves are being depleted faster than they can be replenished by rain.
Pollution degrades water and decreases supply.
This situation is being exacerbated by pollution of water resources, which effectively decreases water available for human use. Pollution from industrial, domestic and agricultural sources continues to severely degrade water quality in many rivers, lakes, and groundwater sources.
Water quality in most of the developed countries has steadily improved in recent years, but in the developed world there is accelerating contamination of usable water supplies, especially in rapidly urbanizing areas. This scenario is very relevant to T&T.
T&T and other developing countries undergoing rapid industrialization are now faced with the full range of modern toxic pollution problems - eutrophication, heavy metals, acidification, persistent organic pollutants - while still struggling to deal with traditional problems of poor water supply and lack of sanitation services. The pollution threat is particularly serious when it affects groundwater supplies, where contamination is slow to dilute and purification measures are costly.
More efficient use of water can increase supply.
More efficient use of water is one of the key opportunities to improve the available supply of water.
According to the World Resources Institute, agriculture is responsible for about 70% of global water use, and 35% in T&T. Improved efficiency in irrigation systems thus has a huge potential to save water. Inefficient irrigation systems waste up to three quarters of the total water pumped through evaporation or runoff before it reaches the intended crop.
More efficient technologies - including drip irrigation systems, lining of irrigation canals, more efficient sprinklers, and better irrigation timing and volume control - are beginning to come into limited use in a few countries and have proved effective at reducing water use. However, these new technologies have not yet been widely adopted. For example, water-efficient drip irrigation is used in less than 1% of the world's irrigated areas.
Significant amounts of water are also lost from leaking collection and distribution municipal systems in T&T as well as worldwide.
Proper pricing of water as an essential and valuable resource will help provide incentives for conservation and greater efficiency. Wasteful subsidies provided to agriculture or industry need to be addressed so that charges are used that better reflect the cost and value of the resource.
World Bank says that new supplies of water will be costly.
However, even with measures to (1) contain the growth of demand and (2) use water more efficiently, new supplies will be needed. The World Bank has estimated that the financial and environmental costs of tapping new supplies will be, on average, two or three times those of existing investments, because most of the low-cost, accessible water reserves have already been exploited
A ridiculously costly desalinisation option is being pursued in south Trinidad. Surely other measures for better watershed protection, less leakage in distribution systems, and increased efficiency of use could have been pursued. What will be the solution for Tobago?
The right of the population to receive a clean and reliable supply of water must be recognised. Tobago needs a comprehensive programme including expansion of plants, repair of lines, proper costing of water to various users, and outreach programmes promoting water conservation methods for agriculture, tourism and in the home. - Nicole Leotaud, Education Coordinator, ET - 16th October 2000