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LARGE-SCALE DEVELOPMENT PROJECTS in the VENEZUELAN ORINOCO WATERSHED and THEIR ENVIRONMENTAL IMPACT STUDIES by J

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LARGE-SCALE DEVELOPMENT PROJECTS in the VENEZUELAN ORINOCO WATERSHED and THEIR ENVIRONMENTAL IMPACT STUDIES by J Reprinted from; J. D. Wiebe, E. H. Kustan & S. Hum (editors).1984. "Environmental Planning for Large-Scale Development Projects". Final Report of the International Workshop on Environmental Planning for Large-Scale Development Projects, héld at Whistler, British Columbia, Canada, October 1983. Vancouver, B.C.,Canada. 339 pp. LARGE-SCALE DEVELOPMENT PROJECTS IN THE VENEZUELAN ORINOCO WATERSHED AND THEIR ENVIRONMENTAL IMPACT STUDIES by J. E. Rabinovich* Centro de Ecología instituto Venezolano de Investigaciones Cientificas Caracas, Venezuela E. I. Buroz Oficina Técnica Caura S.R.L. Caracas, Venezuela and D. Gonzalo Graduate Student Introduction Historical, economic and ecological factors have led towards a polarized development of Venezuela: most of the population is concentrated along two main axes: the coast and the Andes. Many important natural resources are located in areas with a population vacuum; that emptiness is crossed by one of the giant rivers of the world, the Orinoco. The river's watershed is not only the source of a major hydroelectric potential, but it also offers the possibilities of massive material'and human transportation through a network of tributaries. Thus, Venezuela is looking towards this watershed as an alternative for the present style of growth. Ambitious multimillion dollar development plans are being evaluated and no doubt many potential environmental effects exist. The government wanted to anticipate these effects in the most preliminary phases of these plans, and a workshop was organized to obtain an indication of the possible potential environmental impacts and provide a guide to the field studies necessary to assess specific consequences. The Orinoco-Apure Project The Orinoco-Apure Project (OAP) has a specific task; to perform the studies and analyze the strategies for an integral use of the Orinoco-Apure fluvial system in connection with national, regional and local development plans. 1 Geographical setting Venezuela is located north of the Equator, (roughly between 1 and 12 degrees north latitude) and its bordering countries are Brazil in the south, Colombia in the west and Guayana in the east; the Caribbean Sea limits Venezuela in the north. (Figure 1) The Orinoco River crosses the * On sabbatical leave at the Instituto Nacional de Diagnostico e Investigacion de la Enfermedad de Chagas "D.M.F. Chaben", Buenos Aires, Argentina. 212 Venezuelan Llanos, splitting the country roughly in half. The degree of concentration of the present-day situation of Venezuela is exemplified by the following figures: 958 of the population occupies 108 of the territory, representing 978 of the working force and producing 948 of the country's territorial raw product. In that 108 of the occupied land the population density averages 150 people/km2 but has at its disposal only 5% of the fluvial resources. 2. Physical Setting The Orinoco--Apure watershed expands over 830,000 km2, of which 640,000 km2 are in Venezuelan territory and the rest belongs to Colombia. The Orinoco River receives 194 main affluents (95 on the right and 99 on the left margin), and more than 2,000 small rivers, ravines and creeks. The Orinoco River is born in the Sierra de Parima in the south of Venezuela; it describes a wide arch going first to the west, then north, and finally east, collecting water from 15 out of the 20 states of Venezuela along a stretch of 2,063 km, before discharging into the Atlantic Ocean, At its widest point there are 20 kms between the two margins. Transporting 1.4 x 1012m3 of water per year it constitutes the third largest river in the. world. This volume of water carries 200,000 metric tons of sediments into the ocean, after creating the Orinoco Delta, that spans over 20,000 km2. The average annual discharge is in the order of 38,000 m3/sec, with an average minimum during the dry season of 5,000 m3/sec, and an average maximum of 70,000 m3/sec after the rainy season, 3. Environmental Setting Due to its latitudinal parameters the Orinoco watershed has an isothermic regime with annual averages that go from about 20°C in the high altitude mesas near the source of,the Orinoco River, to near 30°C in some of the flat areas, almost at sea level, in the middle and upper reaches of the river. Precipitation shows a relatively seasonal pattern with the rainy season between May and November (peak rains in July and August). The average annual precipitation goes from low values of the order of 100mn/year near Ciudad Bolivar, up to almost 4,900 mm/year at the headwaters of the Paragua River, one of the main tributaries of the Orinoco River. Several vegetation types are present in the Orinoco watershed: various kinds of rainforests (evergreen, deciduous and semideciduous; gallery, cloud forest), chaparral, and various types of savannahs. The wildlife present in the watershed is also very rich, and includes several species under risk of extinction (the Orinoco Caiman - Crocodylus intermedius; the giant nutria - Pteronura brasiliensis; the arrau turtle - Padocnemis expansa; the jaguar - Pantera onca; and the ocelot - Felis pardalis, among others). 3 4. Economic Setting The Orinoco watershed is a region rich in hydrological and other natural resources, both renewable and non-renewable. Spread over several hundred thousand square kilcmeters, the following are sane of the various economic enterprises either under way or under consideration in the planning scheme of the OAP: (a) LIVESTOCK AND AGRICULTURE: Several multiple-purpose dams (Guanare-Masparro, Turen II, Uribante-Arauca) and a giant program of water retention earth dams called "modulos", in the Llanos (savannahs). (b) FORESTRY: Pine plantations and forest reservations. (c) HYDROELDCTRICITY: Dam constructions in Uribante- Caparo, Bocono-Tucupido and the final stage of the Guri dam. (d) MINING: Bauxite at "Ws Pijiguaos", expansion of iron mining at Cerro Bolivar, and gold mining at El Callao. (e) OIL: Exploration and exploitation of the heavy oil strip north of the Orinoco River (about 800 km long and 50 km wide). (f) NAVIGATION: Maintenance of the navigation canal.between Ciudad Guayana and Boca Grande, and dredging and buoy setting in the upper and middle Orinoco. (g) FISHERIES: Freshwater fisheries in the main Orinoco River and its flooded banks, as well as oceanic fisheries near the Orinoco Delta. (h) RECREATION: Tourism developments around the fluvial system, parks, lagoons, reservoirs and historic sites. 5. Institutional Setting The OAP is administratively dependent on the Planning Division of the Venezuelan Ministry of the Environment and Renewable Natural Resources. However, it operates as an element of technical support to an Interinstitutional Ccnmittee constituted by the following seven governmental institutions: (a) the Ministry of Energy and Mines, (b) the Ministry of Transportation and Cannunications, (c) the Venezuelan Corporation of Guayana, (d) the Electric Ccxnpany of Caroni (EDELCA), (e) the National Dredging Institute, (f) the Autonomous Institute of State Railroads, and (g) the Ministry of the Environment and Renewable Natural Resources. These institutions signed, on July 18, 1980, the "Agreement for the Coordination and Execution of Studies for the Exploitation of the Orinoco River and its Affluents". 4 The Environmental Impact Preassessment Workshop During several years the OAP had been funding field research projects to gather data (hydrological, physical and biological) in order to anticipate environmental impacts of some of the above-mentioned developments. As hundreds of thousands of dollars were spent and a mass of incoherent information started to pour in, the funding procedure was questioned, and a preassessment workshop was requested. A two day workshop was organized with the following objectives; (a) GENERAL OBJECTIVE: to provide coordination and coherence to the field environmental studies carried out at that time and to be carried out in the future in relation to the OAP. (b) SPECIFIC OBJECTIVES; (i) Preassessment of environmental impacts of some of the main developments in the OAP. (ii) Ranking of those impacts (iii) Identification of field research projects associated with the ranked impacts. (c) A PARTICULAR OBJ CTIVE: to facilitate the interaction of investigators active in the research problems associated with the OAP. 1. Workshop Effort Although the workshop itself was only a two-day effort, the total time used in preparing for the workshop plus the analysis of results and report writing involved about 4 months; the effort was distributed in the following way: (a) Pre-workshop phase: it lasted 2 months and involved 500 man-hours of work; the workshop was structured, the agenda prepared, the participants selected and contacted, and special forms developed. A 120 page-long document to serve as support for the participants was elaborated with descriptions and quantative information on the developments, the environment and the economics. (b) The workshop itself: in addition to the 5 workshop staff,18 participants were present representing the following fields of endeavour: ecology, botany, wildlife, systems analysis, air pollution, planning, agronomy, land use, navigation, fisheries, sociology, hydrology, hydrochemistry,and industrial engineering. A soil specialist that was invited did not show up. A total of 450 man-hours of©effort was invested in the workshop. (c) Post-workshop phase: for two months the results were analyzed and synthesized and the final reports to the Ministry of the Environment were written. The reports covered two aspects separately: a volume with results (and Annexes) and a volume with an analysis and evaluation of the workshop methodology (also with Annexes). A total of 500 man-hours was invested in this phase. 5 The total effort spanned over four months and involved about 1500 man- hours. 2. Workshop Procedures The idea behind the workshop was to have a highly structured activity so that all participants would be yielding as much as possible in such a short time. The essence of the procedures are shown in Figure 2.
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