Water Pollution In The Republic Of Trinidad And Tobago

  • May 2020
  • PDF

This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA


Overview

Download & View Water Pollution In The Republic Of Trinidad And Tobago as PDF for free.

More details

  • Words: 4,668
  • Pages: 14
1

CHAPTER ONE INTRODUCTION The Republic of Trinidad and Tobago is the southern most isles of the Caribbean, and is completely surrounded by waters of the Caribbean Sea. The two islands, Trinidad (4,828km²) and Tobago (300km²), both have tropical climates, the mean temperature averaging 27°C. Both islands experience a dry season between January and May and a wet season from June to December, although there is sufficient evidence to suggest that there may be now two wet seasons, but that is a different story. The annual rainfall in Trinidad is approximately 200cm (40in). Trinidad lies on the tectonic boundary between the South American and Caribbean plates, with a geology largely composed of faulted sediments and lowgrade metamorphic rocks. The fissured limestone northwest of the Northern Range has small springs, while the alluvial deposits within the metamorphic rocks form coastal aquifers. To the east, the Port-of-Spain ‘Gravels’ consists of gravels, limestone and alluvial deposits, which form the coastal Port-of-Spain aquifer and is over 91.4m (300ft) deep and extremely porous. Apart from seawater and rainfall, water is also accessible from rivers, swamps, reservoirs, dams, watersheds, aquifers and mangroves. Ultimately, only 0.014% of the earth's total volume of water is easily available to us for agricultural, industrial, and domestic purposes. This water exists in a variety of forms, including surface water, soil moisture, groundwater, water vapour, and rivers. Through the Water and Sewerage Authority (WASA), water is distributed throughout the republic, but is first treated in its various water treatment plants. The plants addressed in this project include the following: • • • • •

Caroni - 63 million galvanized surface water from a river; Navet - 20 million gal/d surface water from a dam impoundment; North Oropouche - 20 million gal/d surface water from a river; Freeport - 3 million gal/d groundwater plant removing iron; and Hollis - 1.2 million gal/d surface water from a dam impoundment

This report will seek to identify the role, function and mandate of WASA, including, but not limited to, the all too important responsibility it plays in managing and / or controlling water pollution. The report will also explore the areas in the country that are affected by water pollution, as well as offer recommendations to manage and control the problem.

2

CHAPTER TWO THE ROLE, FUNCTION AND MANDATE OF THE WATER AND SEWERAGE AUTHORITY (WASA) The Water and Sewerage Authority of Trinidad and Tobago (WASA) is the sole water and sewerage provider in Trinidad and Tobago and came into being by Act No. 16 of Parliament in 1965. The mandate extends to the delivery of a safe, reliable and efficient water supply to satisfy the demand of domestic, agricultural and industrial customers throughout the country. The purview of the authority also extends to the sewerage treatment plants and sewerage systems, the constructing and developing of such further sewerage works, as it considers necessary or expedient. It also maintains and develops waterworks and other property related thereto, providing water supplies and administering the supply of water, and promoting the conservation and proper use of water resources. There has been a steady increase in the demand for water in the Republic, but there has not been the proportionate investment in infrastructure and the identification of alternative sources of supply, with specific reference to the industrial sector. WASA's future operations are also viewed in the broader context of Government's developed nation status agenda. The main goal is the requirement for the population to have access to a reliable and high quality water supply on a 24 hour / 7 days per week basis to the entire population, in keeping with the Government's vision for the country to attain developed world status by 2020. Currently, 26 % of the population gets a 24/7 water supply; the rest receives water on a weekly schedule. But there are many communities still without a regular water supply and this is being addressed through an ongoing development plan. The Minister of Public Utilities is the line Minister for WASA and both are aligned to carry out the policy of the Government in relation to water and sewerage services. Another important responsibility of WASA is the Water Resources Agency, which reports to the Board but operates separately in managing water resources. Based on an evaluation on water supply and sanitation development conducted in 2000 by Evaluacion de Los Servicios de Agua Potable y Saneamiento en las Americas, a consulting firm worked on "detailing of a clearly articulated water resource management strategy for Trinidad and Tobago to meet the projected medium and long term water needs of the country on a sustainable basis." According to a WASA report, it was stated that at the end of 2005, Trinidad and Tobago stood well on the way to attaining the United Nations’ Millennium Development Goal (set for 2015) with respect to achieving adequate drinking water and sanitation arrangements, thus: although around 92% of the 1.3 million inhabitants currently have access to safe drinking water, this supply is only available to around 26% on an uninterrupted, 24/7 basis. The remainder of those supplied receive water on a weekly schedule, while a

3 number of communities are still without a regular supply. Some 30% of the population has a sewerage connection, while 58% rely on soak-aways or septic tanks and Trinidad and Tobago boasts one of the most effective water and sewerage systems anywhere in the Caribbean. But even though WASA, the country’s Water and Sewerage Authority, produces 200 million gallons of water per year – twice as much as is consumed in the larger island of Jamaica – demand continues to grow, especially from industrial customers. A single steel factory or fertilizer producer might consume four million gallons alone. Currently the biggest industrial demand for water comes from methanol production, which is enjoying a boom thanks to ever-increasing quantities of natural gas piped from offshore fields (www.wasa.gov.tt/). WASA Chief Executive Officer, Errol Grimes further states: “Our country is one of the largest exporters of methanol. Water is a raw material in this production. They split the water molecule and use hydrocarbons from the oil industry to make methanol. That is good business for us as the supplier of the raw material.” Given this state of development, it would be safe to surmise that WASA is continuing its growth towards its quest for developed world status by the year 2020. The following chapter will critically analyse the areas in Trinidad and Tobago that are affected by water pollution.

4

Water and Sewerage Authority (WASA), El Socorro Water Works

Water and Sewerage Authority (WASA) Maraval Water Treatment Plant

CHAPTER THREE

5

ANALYSIS OF AREAS IN TRINIDAD AND TOBAGO THAT ARE AFFECTED BY WATER POLLUTION The term Water Pollution generally refers to the adverse changes in water quality usually as a result of human activities. It is the contamination of any body of water with materials that are considered harmful to human health and to the environment. In Trinidad and Tobago, the problem of water pollution is widespread and caused mainly by human activities resulting from littering, unsettled quarry wash, industrial plant and factory waste, overuse of fertilizers and pesticides, bush fires, slash and burn and deforestation, waste oils and untreated or poorly treated sewerage. This chapter will seek to critically analyse areas in Trinidad and Tobago that are so affected.

Caroni River bank depicting debris, sediments and young Caiman. But before we can appreciate the sources of water, we must understand that water may come from either surface water or ground water. Surface water may be described as water, which travels or is stored above the ground. This would include rivers, swamps, reservoirs and the sea, which we should not drink.

6 Surface water may also include ‘run-off’ water, which is water that runs off of roofs, guttering, parking lots and roadways. Of course, this water may be contaminated with trash, oil and other debris. Surface water on the whole needs to be treated before it can become potable as it contains similar debris, which can easily get into rivers and reservoirs. Ground water on the other hand is underground water and may be found in aquifers, watersheds and springs. Groundwater flows through layers of sand, gravel, rock and clay, which act as a natural filtration system thereby keeping the water clean (see illustration below).

Ground water may also become polluted by agriculture in the form of fertilizers, pesticides and from oil production, refining and toxic chemicals, inclusive of heavy metals, which wash into the soil and get into aquifers. The disposal of sold waste in landfill sites such as the Beetham and Claxton Bay dumps are also threats, as this results in leaching. The Beetham dump, being situated close to the sea, may result in seepage being transported to the coast thru the adjoining wetlands. Seepage emanating from poor or inadequate domestic waste particularly sewerage, burial grounds as well as seepage from leaks emanating from gas station underground tanks, are also part of the problem, but all in all, ground water does not need as much treatment as surface water. Pollution of surface water in Trinidad and Tobago not only affects the production of potable water but also the ability of the rivers to provide productive habitats for fish. The Caroni River Basin is hugely affected in this way and this is also applicable to the largest watersheds, which contain the major river systems (and fresh water ecosystems), such as North Oropouche, Navet, Ortoire, South Oropouche rivers and their associated wetland/swamp areas. All rivers and streams flowing through urban areas are heavily polluted and most industries outside sewered areas discharge untreated waste directly into rivers or the sea. Major systems in Tobago that are affected include the Richmond, Goldsborough and Hillsborough rivers. The major threats to the management of watersheds and freshwater ecosystems in Trinidad and Tobago include the threat from soil erosion, deforestation, shabitation on steep slopes, annual bush and forest fires, and indiscriminate and

7 unplanned construction. These can reduce the free flow of fresh water resulting in changes in composition of fresh water plants, sedges and invertebrate composition and leads to flooding mainly due to poor drainage and maintenance. Diego Martin, Maraval, Port of Spain and areas along the east-west corridor are generally affected in this regard. Further degradation of the watershed areas can result from pressure on land for housing and poor land practices, reduced crop and land productivity. A poor system of logging In Tobago has resulted in similar problems. Deforestation interferes with the natural harmony of watersheds in the country as it involves indiscriminate clearing and degradation of forests for housing and urban development. Additionally, shifting cultivation and squatting, loss of forest and protective vegetative cover by forest and bush fires, quarrying operations and road construction and cultivation on steep slopes without the application of appropriate soil and water conservation measures all contribute to the problem. Many of the rivers that drain the foothills of the Northern Range are affected by high sediment load as a result of decreased vegetation in the upper catchment area. During high rainfall, the Diego Martin, Maraval, Maracas/St. Joseph, Tacarigua and Arima rivers are affected. The Caroni Basin is already under threat from poor land use practices, including the deforestation of the Northern Range, which results in consistent flooding in the lower regions of the Basin. The fresh water system within this region has been deteriorating rapidly due to pollution from a variety of medium sized industries, particularly poultry rearing and quarrying. Pesticides and fertilizers from agricultural use also play a significant role in the dilemma Salt-water intrusion is also a major cause for concern. A number of aquifers are opened ended to the sea. The Cocorite well field and Upper El Socorro Gravels in the North West of the island are examples where salt-water intrusion resulted in the abandonment of several good producing wells. This has also interfered with the groundwater systems of the Northwest Peninsula Gravels (Port of Spain/Cocorite), the Northern Gravels (El Socorro), the Mayaro Sandstone (East Coast of Trinidad) and the Valsayn Aquifer. Large-scale drawdown on the Northern Gravels due to population increase along the east-west Corridor has decreased water table levels in this area. This drawdown has been spurred on by deforestation of the surrounding watershed forests and widespread change of land-use into housing settlements. The end product of these activities result in the decrease of percolation (the filtering of water (and the nutrients it carries) through the soil) and aquifer replenishment is reduced. Sea-level rise along the southwest coast of Trinidad has threatened critical areas such as the Point Lisas Industrial Estate, a major Gross Domestic Provider (GDP) provider. Seawater encroachment in the coastal regions of southwest and east Trinidad continues to be an engineering challenge. Such encroachment has often resulted in severe erosion of the coastal areas. Limited encroachment and erosion continues to be experienced in some coastal areas of Tobago. The beaches of Vessigny, La Brea and Mayaro in the south of Trinidad have been affected by the oil spills and petroleum hydrocarbon contamination emanating from

8 the petroleum-based industry. Such spills have had short-term damaging impacts on the coastlines, particularly in the Gulf of Paria. Contamination is believed to result from shipping activities, ballast discharge and oil spills from tankers. The foothills of the Northen Range and the western coast of Trinidad are affected by effluent outfall resulting from the release of agro-chemicals and the indiscriminate dumping of agricultural and industrial waste and cleaning agents used in households. These industries include paint and metal finishing, agro-processing, petrochemicals and distilleries. No wonder the mangroves in the Beetham area are compromised due to indiscriminate waste emanating from the nearby Fernandes Distilleries, as well as leaching from the nearby dump. Effluents from oil (and sugar cane refining) particularly affect the rivers in south Trinidad. Petroleum products discharged into the environment stems from the improper disposal of vehicle oils into open drains. Leaking tanks, washings and improper disposal of waste oils also affect other areas in the country. All told, these factors have lead to the widespread contamination of waterways, along with lead pollutants from vehicles using leaded gasoline. With respect to agricultural pollution emanating from the sugar industry, the main areas affected were the Caroni, Couva and Cipero rivers, coastal mangroves and the beachfront. According to a Water Pollution Management Programme Report sanctioned by the Environmental Management Authority, stated thus: Many of the rivers that cross the East/West Corridor and those that drain the western part of Trinidad are affected by industrial pollution, these include Cipero (cane sugar production and refining, service stations), Guaracara (oil refining, service stations), Couva (petrochemicals, sugar cane production, service stations, agro-processing), Guayamare (rum distilling, service station), Caroni (rum distilling, quarrying, service stations, agroprocessing, manufacturing of paints, other chemicals and metal fabricated products), Santa Cruz/San Juan (quarrying, agroprocessing, service stations), Maracas/St. Joseph (quarrying, service stations, agro-processing including brewing, chemicals), Tacarigua (service stations, agro-processing, chemicals and metal fabricated products) Mausica (service stations, agro-processing), Arima (service stations, agro-processing, quarrying, chemicals), Guanapo (quarrying), El Mamo (quarrying), North Oropouche (quarrying). In Tobago industrial activity is concentrated mainly in the southwest where there are only a few major rivers; the Steele River receives agro-processing wastewater.

Compounding the problem is the indiscriminate disposal of domestic refuse and solid waste in huge quantities in various watercourses in Trinidad and Tobago. This waste is made up of faeces, animal entrails, chicken feathers, used styrotex and plastic containers and cumbersome household items. This domestic refuse and solid waste contribute to clogged waterways, resulting in highly offensive odours that may be unhygienic. The refuse may also dissolve to produce chemical residues, which lower

9 water quality. This is the case with respect to Poole, Erin, Arima, and Cunupia Rivers and Hillsborough River in Tobago.

While the Water and Sewerage Authority (WASA) operates over twenty (20) sewage treatment plants in the country, there are approximately over one hundred and fifty such plants that exist otherwise, which are poorly maintained and pose a serious health threat. Most of these treatment plants operate inefficiently, producing effluent, which exceeds the standards for faecal coliform and biological oxygen demand. Nonfunctional sewage treatment plants, livestock farms and overflowing septic tanks, and cesspit latrines also discharge significant quantities of organic waste into the nation's waterways. According to a WASA report, it is estimated that farm waste has been estimated to produce over fifty-five percent (55 %) of the total waste load. Serious contamination of over four (4) waterways has been attributed to primarily farm waste. The total domestic and livestock waste for Trinidad and Tobago was also estimated as 10.4 million kilograms/year with 45 % being contributed from domestic sources and 55 % from livestock. Meanwhile, Tobago accounts for four percent (4 %) of both the domestic waste and livestock waste (www.wasa.gov.tt/) Another alarming discovery, according to some sources (anon), was that high nitrate levels were detected at various times in the Port of Spain and Valsayn Gravels. These high levels have been linked to leaching from nearby cemeteries. While we can agree that nature by itself, may interfere, for lack of a better word, with the equilibrium of its own ecosystems, this report has clearly shown that it is man who has made the most significant contributions to the deterioration of Trinidad and Tobago’s (and the planet’s) water quality. The indiscriminate release of high levels of organic material, toxic waste and pathogens from domestic, industrial and agricultural sources, as well as indiscriminate and unsanctioned quarrying activities, deforestation, sewage discharge, domestic solid waste dumping and the excessive use of agrochemicals and petrochemicals, which has led to high levels of nutrient, pesticide and heavy metal build-up, has also exacerbated the problem. It is quite clear that firm and drastic action is needed to manage and control the escalating problem. Decisive steps need to be taken, coupled with a plan of action and goals for implementation. These recommendations for control will be addressed in the following chapter.

10

CHAPTER IV RECOMMENDATIONS TO MANAGE THE PROBLEM Every intelligent people should be wise enough not to pollute water in any way. This adage rings true and is reflected in the following quote from Rachel Carson’s ‘Silent Spring’, where she postulates: Man's attitude toward nature is today critically important simply because we have now acquired a fateful power to alter and destroy nature. But man is a part of nature, and his war against nature is inevitably a war against himself… [We are] challenged as mankind has never been challenged before to prove our maturity and our mastery, not of nature, but of ourselves (Carson, R. 1964). The 1st Law of Thermodynamics states that matter and energy cannot be created or destroyed, while the 2nd Law states that matter and energy tend to disperse. In this context, we should never throw anything away and when we do throw something away, there is no guarantee that it will stay there. In natural processes, matter and energy tend to flow in cycles and environmental quality is maintained by these cycles and the interactions between them. Ergo, environmental impacts arise from the disturbance of these cycles and their relationships beyond their threshold limits (Andrew Zimmerman Jones, About.com). Pollution control is a term used in environmental management. It means the control of emissions and effluents into air, soil or water. Without pollution control, the waste products from consumption, heating, agriculture, mining, manufacturing, transportation and other human activities, whether they accumulate or disperse, will degrade the environment. In the hierarchy of controls, pollution prevention and waste minimization are more desirable than pollution control. The objective is to bring the level of pollutants to that which is acceptable. We cannot eliminate it. What determines acceptable level: Legislation (EMA) or Scientific Data or Information. It must be clearly understood that pollution of any kind, far less water pollution, cannot be completely eradicated, but effective measures can be put in place to control or manage the problem to an acceptable and less dangerous level. However, this cannot be achieved without first educating the stakeholders and raising awareness to a level where attitudes can improve and cultures may become progressive. Education may include, but not limited to, a schools outreach programme and graphic public exhibitions on the operations of water and wastewater treatment plants, and the environmental dangers caused by indiscriminate and unsanctioned deforestation, slash-and-burn, illegal quarrying and other malpractices that pollute the water courses.

11 To augment this, a legislative framework must be developed to address directly or incidentally the existing problem and give effect to an integrated water resource management approach so as to guarantee that water quality is provided for people, food and nature. The current legislative instruments, the Water and Sewerage Act (1980 revised), the Public Health Act (1950), the Waterworks and Water Conservation Act (1980 revised), the Environmental Management Act (2000) and the Water Pollution Rules (2001) are simply not enough and needs to be upgraded in order to become more effective. Government initiatives should include a national reforestation and watershed rehabilitation programme to improve the protection of freshwater sources, as well as a community-based programme for the protection and enhancement of the environment. Simple and non-complex methods may be utilised to deal with pollution, according to the document referred to in the previous chapter (Water Pollution Management Programme Report), thus: Domestic Waste: • • •



• •



Keep litter, pet wastes, leaves, and debris out of street gutters and storm drains--these outlets drain directly to streams, rivers, and wetlands. Apply lawn and garden chemicals sparingly and according to directions. Properly dispose of household hazardous wastes. Many common household products, (paint thinners, moth balls, drain and oven cleaners, etc.) contain toxic ingredients. When improperly used or discarded, these products are a threat to public health and the environment. Do not pour hazardous products down any drain or toilet. Do not discard with regular household trash. Learn about natural and less toxic alternatives and use them whenever possible. Contact Solid Waste Management Office for information regarding hazardous waste collection in your area. Recycle all used motor oil by taking it to a service station or local recycling centre. Motor oil contains toxic chemicals that are harmful to humans and animals. Do not dump used motor oil down storm drains or on the ground. Control soil erosion on your property by planting ground cover and stabilising erosion-prone areas. Limit the amount of impenetrable surfaces in your landscape. Use permeable paving surfaces such as wood decks, bricks, and concrete lattice to let water soak into the ground. Encourage local government officials to develop construction erosion/sediment control ordinances in your community. Forestry:



Use proper logging and erosion control practices on your forestlands by ensuring proper construction, maintenance, and closure of logging roads and skid trails.

12 • • •

Allow thick vegetation or buffer strips to grow along waterways to slow runoff and soak up pollutants. Plant trees, shrubs, and ground cover. They will absorb up to 14 times more rainwater than a grass lawn and don't require fertilizer. Report questionable logging practices to forestry division and other water quality agencies. Agriculture:

• • • • •

Manage animal waste to minimise contamination of surface water and ground water. Protect drinking water by using less pesticides and fertilizers. Reduce soil erosion by using conservation practices and other applicable best management practices. Use planned grazing systems on pastureland. Dispose of pesticides, containers, and tank rinsate in an approved manner.

Deforestation, as outlined in this report, contributes to several negative ramifications but in Trinidad and Tobago, there does not seem to exist an understanding that inappropriate actions, such as this, taken within the upper regions of our watersheds can negatively impact on downstream areas including our coastal zones. The resulting sedimentation of our coastal areas at the outfalls of watercourses requires expensive engineering and maintenance solutions such as dredging. Salt water intrusion may be controlled by the pumping of aquifers within their safe yield values, drilling wells further inland from the coast line and the frequent monitoring of coastal observation wells for water level fluctuations and quality (chlorides). Technical issues, such as desalination, technology and water recycling, establishment of a hydro-technical monitoring network and capacity building, are also critical to successful management of water resources. Indiscriminate dumping is one of the ways that mankind has imposed a threat upon his own environment. Awareness and Education, as stated earlier may be useful in combating the problem, however, treatment of the source by disinfecting before dumping into the distribution system may help. On a local scale, there are threats by point source pollution and most aquifers are very vulnerable, in the absence of thick overlying clay layers, to the infiltration of contaminants. Controlled dumping and the monitoring of wastewater discharges on a regular and sustained basis are measures that can be used to avoid such contamination. Remote disposal of waste, in areas that are not in proximity with aquifers are also applicable and the design should be modernised and the system treated. The problem of inefficient sewage waste disposal may be remedied by choosing septic tanks or WASA sewage mains (Sewerage Treatment Plants) as opposed to pit latrines. Biodegradable waste can be buried in one’s backyard instead of ending up in the Port of Spain or Claxton Bay dump, where it goes untreated.

13

CONCLUSION Every individual, in carrying out his / her daily activities, has an impact on the environment and in nearly all cases, that impact will be negative. Conversely, every individual has the opportunity to reduce his /her impact and in some cases, even improve the environment. Pollution Control Management is the process by which systems are implemented to reduce that impact and perhaps improve the existing conditions. It may be considered as making a major contribution to the wider strategy for meeting the requirements for a sustainable society and focuses very much on the role that individuals will play in achieving it. As stated earlier, every individual has an impact on the environment so it is the responsibility of every single person to minimise that impact and improve it wherever possible. The growth of industry and technology has increased the impact that mankind will have on his environment and made it even more severe. As illustrated in this report, there are still frequent episodes of water pollution arising from accidental or deliberate disposal of harmful substances on land, dumping of petro-chemicals at sea, over-use of pesticides and fertilizers and poor sewage systems, all of which results in contamination of both surface and ground water. The impact of deforestation is becoming increasingly obvious, for example, there is increasing damage from floods that are more devastating as a result of the loss of the forests that previously reduced rainwater run-off to aquifers, rivers and streams. Deforestation includes the use of slash and burn techniques where valuable timber is harvested and the remaining trees, shrubs and vegetation are burnt. This also exists in urbanisation projects, where the land is indiscriminately eroded in the construction of homes. This has the double impact of increasing carbon dioxide emissions to the atmosphere thus contributing to global warming and destroying trees and vegetation that have an important role to play in absorbing carbon dioxide as part of the photosynthesis process. Stakeholders can introduce pollution management systems and work towards sustainability in everything they do. The government and Statutory bodies have an important role to play in encouraging a more proactive approach to controlling pollution and the international community can also lead the way, for example, by the Ramsar Convention. It must also be known that there is some controversy surrounding certain information regarding environmental management, but our focus must remain on the underlying causes and not their signs and symptoms. One thing is clear, however, failure to address this burning issue of continuing water pollution and degradation could have a chaotic impact and effect on the future of the earth and the human race.

14 The supreme reality of our time is...the vulnerability of our planet John F. Kennedy (1917-1963)

Related Documents