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Tidal power
Marine Pollution Bulletin
The studies carried out by the Severn Tidal Power Group have included extensive work on both engineering and environmental matters. The results were reported in 11 papers. On the engineering aspects, the principal change since the last conference in 1986 has been the increase in the proposed installed capacity from 7200 MW to 8640 MW, based on 216 turbines with variable runner blade angle and fixed distributer guide vanes, referred to as 'Kapeller' machines, and 40 MW capacity generators. This very large capacity would require special measures to allow the power to be absorbed satisfactorily by the grid system. The cost of these is indicated by the allowance of between £850M and £1230M for strengthening of the grid, the range depending on the proportion of underground cable required. The annual energy output of the barrage is estimated at 17 TWh, tlais being an interpolated figure between the results of computer models with and without taking into account the dynamics of tidal flows into and out of the estuary. This represents about 7% of the present demand for electricity in England and Wales. The environmental studies carried out of the Severn barrage continue the work of previous studies and, to some extent, form the basis for the more extensive studies that will be required before the barrage could be promoted. Some 59 individual studies were carried out by specialists, a substantial proportion being connected with sediment properties and movements because these govern to a large extent the ecology of the estuary. One conclusion that seems to be emerging is that the Severn barrage, once built and in operation, would have few adverse effects on the environment and some significant beneficial effects as regards the stability of the sediments within the enclosed basin and hence on the productivity of the intertidal flats. However, a paper presented on behalf of the local authorities flagged up several areas of concern, for example with respect to the traffic during construction, the effect on port traffic, land drainage, and pollution in the estuary. Work on the Mersey barrage is being carried out by or on behalf of the Mersey Barrage Company, and is at an earlier stage; for example the choice of location of a barrage has been less clear and only recently has the decision been made to concentrate future studies on the inner of two lines, largely to avoid having to provide locks for the largest oil tankers using the estuary. The preferred choice of turbine type is a double-regulated, 8 Marine Pollution Bulletin, Volume 21, No. 3, pp. 160-161. 1990. 0025-326X/90 $3.00+0.00 m diameter turbine linked to a generator via a step-up Printed in Great Britain. © 1990 Pergamon Press plc gearbox housed in an open pit. For the inner line, 26 turbines with 25 MW generators are preferred, giving a Tidal Power total capacity of 650 MW and an estimated annual The third conference on tidal power organized by The energy output of 1.24 TWh. The first of two generic studies presented was the Institution of Civil Engineers was held on 28-29 November, 1989. Some 18 papers were presented and results of a study of the feasibility of building caissons discussed. Three main themes were covered, namely: out of steel, instead of reinforced concrete. This had the results of the latest £4.1M studies of the feasibility been carried out by the Steel Construction Institute. of the Severn barrage; the preliminary results from the The main conclusions were that steel caissons would be second phase of the £1.2M feasibility studies of the competitive in terms of cost, and technically feasible Mersey barrage, currently in progress, and the results of methods of corrosion control are available. The other generic study, carried out by Rendel'generic' studies into methods of construction other Parkman, concerned the use of in-situ construction than precast concrete caissons floated into position.
Don Gamble, Triton Environmental Consultants, Burnaby, B.C., presented a paper, 'Coastal Zone Management in British Columbia: An Evaluation', in which he compared the institutional approaches to coastal zone management in British Columbia and in the State of Washington. He painted a rather black picture of the situation in British Columbia, using Boundary Bay as a case study, and comparing it with Cherry Point, Washington. He suggested that this is due to the fact that there is no comprehensive legislation in Canada, and federal or provincial lead agencies have not been assigned the task of undertaking proactive planning in the coastal zone of British Columbia. The final paper of the Seminar was given by David Marshall, Director of the Pacific, Western and Northern Region, Federal Environmental Assessment Review Office, Vancouver, B.C., on Nn Action Plan for Sustainable Development of Marine and Coastal Resources in Indonesia'. He described the procedure used to develop an Action Plan with a set of medium-term policies and objectives to guide marine and coastal development in a developing country. A package of 'strategic action programmes' was designed to implement these policies and objectives. It addressed: government management; resource protection and management; regional development and planning; coastal community development; business involvement; training, education and extension; and information and research. A Seminar Summary was presented by J. W. Kamphuis, Professor in the Department of Civil Engineering, Queens University, Kingston, Ontario. In the discussion that ensued, a number of participants pleaded for a 'single window' to clear developmental projects rather than having to wade through many jurisdictions. One participant pointed out that the Fraser River Estuary Management Programme was designed to carry out such a function with respect to activities on the Fraser River Estuary. No published proceedings are planned for the Seminar. A bound Programme and Abstracts was provided to all participants and copies might still be available from: Mr. J. C. Day, Natural Resources Management Programme, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6. MICHAEL WALDICHUK
160
Volume21/Number3/March 1990 based on building the main structural walls as diaphragm walls, working from temporary mounds of sand fill. The sand fill would be retained and protected by VLCCs. The method is claimed to have cost advantages over the caisson method, but further development is required. WHile applicable to moderate-size projects such as the Mersey barrage, the opinion was expressed that the concentrations of plant and manpower required to build the power house and sluices for the Severn barrage in a reasonable period of time would present problems of logistics. The conference concluded with a panel discussion.
~tartne Polhttion Bulletin. Volume 21, No. 3, pp. 161-162, 1990, Printed in Great Britain.
An occasional series drawing attention to recent activities of the International Council for the Exploration of the Sea in respect to marine pollution issues.
Marine Pollution, 1989 The ICES Advisory Committee on Marine Pollution (ACMP) is responsible for the provision of advice to the ICES Council and, on behalf of Council, to outside organizations or to individual national administrations or groups of countries at their request. The ACMP produces a report each year in which it publishes its advice both on the various questions put to it and on topics it feels its audience will, or should, find of interest. The 1989 report was published recently by ICES in its Cooperative Research Report Series (No. 167) and is available from the Council's Offices in Copenhagen at a cost of DK100 (approximately £9). This short article gives brief information on some of the main topics covered in the 1989 report. As with previous ACMP reports, a wide range of topics is covered in the 1989 report. Many of the sections provide advice in response to questions raised by the pollution regulatory Commissions, although in some cases in the interest of completeness the advice goes beyond that specifically asked for. In a few instances however the advice merely updates or extends that previously given or presents an interim position pending completion of a particular task. The number of sections and the size of the 1989 report (172 pages) are indicative of the wide range of interests of the Commissions as well as the complexity of the tasks undertaken by the ACMP. In this latter context the report notes that, thanks to the working group structure of ICES, the ACMP was able to draw upon requests from at least sixteen working groups in formulating its advice. A substantial proportion of the report is devoted to matters related to monitoring and data quality. ICES has over a number of years engaged in a series of analytical intercomparison exercises, four are
The main subject was the effects of the privatization of the electricity industry, and the higher effective rates of return to be expected, on prospects for the development of tidal power in the UK. The outlook for the Severn barrage was somewhat gloomy because high discount rates do not take into account the very long working life to be expected from a tidal barrage. The Mersey barrage could be included in the non-fossil fuel obligation and therefore attract some form of subsidy in its early years of operation. CLIVE B A K E R
0025-326X/90 S3.00+0.00 © 1990 Pergamon Press plc
currently underway: nutrients in sea water, suspended particulates in sea water, and the first stages of exercises on polynuclear aromatic hydrocarbons and on chlorinated biphenyls. Brief details of progress on these are provided. In recent years, however, increasing emphasis has been placed on the role of reference materials and, following initial problems, ACMP has revised its earlier advice and now recommends that only experienced laboratories should attempt to use internally produced reference materials for in-house routine quality control purposes; most laboratories would be better advised to use certified reference materials. Attempts to use time-series of data on contaminants in a variety of marine media have highlighted the fact that all too often too little attention is paid to sample and sampling variability and that these can have a major influence on the apparent trends obtained when simple residue data are examined for trends in time. The results of an experiment conducted in the Baltic Sea to study patchiness (PEX) have now been worked up and published (ICES Coop. Res. Rept No. 163). The experiment had revealed extreme patchiness both in space and time. Whilst this is perhaps not surprising, confirmation of the phenomenon also confirms that a single water sample at a station is not enough to characterize the area. This has implications for monitoring both in the Baltic and elsewhere. On a more practical plane, the 1989 ACMP report includes a number of examples showing how the guidelines on the use of benthos to study the impact of point sources of pollutants, that were provided in the 1988 report, have been used in real situations. The 1989 report also includes advice on the procedures that should be used to normalize contaminant data in sediments. This process allows a distinction to be made between the natural and anthropogenic contaminant fractions present in sediments. The guidelines indicate that simplified procedures can be adopted following a full characterization of a particular situation but that it is extremely unwise to select a single normalizing element and assume it will serve the purpose in a new situation simply because it did elsewhere. Recognizing the topical concerns over algal blooms 161
The studies carried out by the Severn Tidal Power Group have included extensive work on both engineering and environmental matters. The results were reported in 11 papers. On the engineering aspects, the principal change since the last conference in 1986 has been the increase in the proposed installed capacity from 7200 MW to 8640 MW, based on 216 turbines with variable runner blade angle and fixed distributer guide vanes, referred to as 'Kapeller' machines, and 40 MW capacity generators. This very large capacity would require special measures to allow the power to be absorbed satisfactorily by the grid system. The cost of these is indicated by the allowance of between £850M and £1230M for strengthening of the grid, the range depending on the proportion of underground cable required. The annual energy output of the barrage is estimated at 17 TWh, tlais being an interpolated figure between the results of computer models with and without taking into account the dynamics of tidal flows into and out of the estuary. This represents about 7% of the present demand for electricity in England and Wales. The environmental studies carried out of the Severn barrage continue the work of previous studies and, to some extent, form the basis for the more extensive studies that will be required before the barrage could be promoted. Some 59 individual studies were carried out by specialists, a substantial proportion being connected with sediment properties and movements because these govern to a large extent the ecology of the estuary. One conclusion that seems to be emerging is that the Severn barrage, once built and in operation, would have few adverse effects on the environment and some significant beneficial effects as regards the stability of the sediments within the enclosed basin and hence on the productivity of the intertidal flats. However, a paper presented on behalf of the local authorities flagged up several areas of concern, for example with respect to the traffic during construction, the effect on port traffic, land drainage, and pollution in the estuary. Work on the Mersey barrage is being carried out by or on behalf of the Mersey Barrage Company, and is at an earlier stage; for example the choice of location of a barrage has been less clear and only recently has the decision been made to concentrate future studies on the inner of two lines, largely to avoid having to provide locks for the largest oil tankers using the estuary. The preferred choice of turbine type is a double-regulated, 8 Marine Pollution Bulletin, Volume 21, No. 3, pp. 160-161. 1990. 0025-326X/90 $3.00+0.00 m diameter turbine linked to a generator via a step-up Printed in Great Britain. © 1990 Pergamon Press plc gearbox housed in an open pit. For the inner line, 26 turbines with 25 MW generators are preferred, giving a Tidal Power total capacity of 650 MW and an estimated annual The third conference on tidal power organized by The energy output of 1.24 TWh. The first of two generic studies presented was the Institution of Civil Engineers was held on 28-29 November, 1989. Some 18 papers were presented and results of a study of the feasibility of building caissons discussed. Three main themes were covered, namely: out of steel, instead of reinforced concrete. This had the results of the latest £4.1M studies of the feasibility been carried out by the Steel Construction Institute. of the Severn barrage; the preliminary results from the The main conclusions were that steel caissons would be second phase of the £1.2M feasibility studies of the competitive in terms of cost, and technically feasible Mersey barrage, currently in progress, and the results of methods of corrosion control are available. The other generic study, carried out by Rendel'generic' studies into methods of construction other Parkman, concerned the use of in-situ construction than precast concrete caissons floated into position.
Don Gamble, Triton Environmental Consultants, Burnaby, B.C., presented a paper, 'Coastal Zone Management in British Columbia: An Evaluation', in which he compared the institutional approaches to coastal zone management in British Columbia and in the State of Washington. He painted a rather black picture of the situation in British Columbia, using Boundary Bay as a case study, and comparing it with Cherry Point, Washington. He suggested that this is due to the fact that there is no comprehensive legislation in Canada, and federal or provincial lead agencies have not been assigned the task of undertaking proactive planning in the coastal zone of British Columbia. The final paper of the Seminar was given by David Marshall, Director of the Pacific, Western and Northern Region, Federal Environmental Assessment Review Office, Vancouver, B.C., on Nn Action Plan for Sustainable Development of Marine and Coastal Resources in Indonesia'. He described the procedure used to develop an Action Plan with a set of medium-term policies and objectives to guide marine and coastal development in a developing country. A package of 'strategic action programmes' was designed to implement these policies and objectives. It addressed: government management; resource protection and management; regional development and planning; coastal community development; business involvement; training, education and extension; and information and research. A Seminar Summary was presented by J. W. Kamphuis, Professor in the Department of Civil Engineering, Queens University, Kingston, Ontario. In the discussion that ensued, a number of participants pleaded for a 'single window' to clear developmental projects rather than having to wade through many jurisdictions. One participant pointed out that the Fraser River Estuary Management Programme was designed to carry out such a function with respect to activities on the Fraser River Estuary. No published proceedings are planned for the Seminar. A bound Programme and Abstracts was provided to all participants and copies might still be available from: Mr. J. C. Day, Natural Resources Management Programme, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6. MICHAEL WALDICHUK
160
Volume21/Number3/March 1990 based on building the main structural walls as diaphragm walls, working from temporary mounds of sand fill. The sand fill would be retained and protected by VLCCs. The method is claimed to have cost advantages over the caisson method, but further development is required. WHile applicable to moderate-size projects such as the Mersey barrage, the opinion was expressed that the concentrations of plant and manpower required to build the power house and sluices for the Severn barrage in a reasonable period of time would present problems of logistics. The conference concluded with a panel discussion.
~tartne Polhttion Bulletin. Volume 21, No. 3, pp. 161-162, 1990, Printed in Great Britain.
An occasional series drawing attention to recent activities of the International Council for the Exploration of the Sea in respect to marine pollution issues.
Marine Pollution, 1989 The ICES Advisory Committee on Marine Pollution (ACMP) is responsible for the provision of advice to the ICES Council and, on behalf of Council, to outside organizations or to individual national administrations or groups of countries at their request. The ACMP produces a report each year in which it publishes its advice both on the various questions put to it and on topics it feels its audience will, or should, find of interest. The 1989 report was published recently by ICES in its Cooperative Research Report Series (No. 167) and is available from the Council's Offices in Copenhagen at a cost of DK100 (approximately £9). This short article gives brief information on some of the main topics covered in the 1989 report. As with previous ACMP reports, a wide range of topics is covered in the 1989 report. Many of the sections provide advice in response to questions raised by the pollution regulatory Commissions, although in some cases in the interest of completeness the advice goes beyond that specifically asked for. In a few instances however the advice merely updates or extends that previously given or presents an interim position pending completion of a particular task. The number of sections and the size of the 1989 report (172 pages) are indicative of the wide range of interests of the Commissions as well as the complexity of the tasks undertaken by the ACMP. In this latter context the report notes that, thanks to the working group structure of ICES, the ACMP was able to draw upon requests from at least sixteen working groups in formulating its advice. A substantial proportion of the report is devoted to matters related to monitoring and data quality. ICES has over a number of years engaged in a series of analytical intercomparison exercises, four are
The main subject was the effects of the privatization of the electricity industry, and the higher effective rates of return to be expected, on prospects for the development of tidal power in the UK. The outlook for the Severn barrage was somewhat gloomy because high discount rates do not take into account the very long working life to be expected from a tidal barrage. The Mersey barrage could be included in the non-fossil fuel obligation and therefore attract some form of subsidy in its early years of operation. CLIVE B A K E R
0025-326X/90 S3.00+0.00 © 1990 Pergamon Press plc
currently underway: nutrients in sea water, suspended particulates in sea water, and the first stages of exercises on polynuclear aromatic hydrocarbons and on chlorinated biphenyls. Brief details of progress on these are provided. In recent years, however, increasing emphasis has been placed on the role of reference materials and, following initial problems, ACMP has revised its earlier advice and now recommends that only experienced laboratories should attempt to use internally produced reference materials for in-house routine quality control purposes; most laboratories would be better advised to use certified reference materials. Attempts to use time-series of data on contaminants in a variety of marine media have highlighted the fact that all too often too little attention is paid to sample and sampling variability and that these can have a major influence on the apparent trends obtained when simple residue data are examined for trends in time. The results of an experiment conducted in the Baltic Sea to study patchiness (PEX) have now been worked up and published (ICES Coop. Res. Rept No. 163). The experiment had revealed extreme patchiness both in space and time. Whilst this is perhaps not surprising, confirmation of the phenomenon also confirms that a single water sample at a station is not enough to characterize the area. This has implications for monitoring both in the Baltic and elsewhere. On a more practical plane, the 1989 ACMP report includes a number of examples showing how the guidelines on the use of benthos to study the impact of point sources of pollutants, that were provided in the 1988 report, have been used in real situations. The 1989 report also includes advice on the procedures that should be used to normalize contaminant data in sediments. This process allows a distinction to be made between the natural and anthropogenic contaminant fractions present in sediments. The guidelines indicate that simplified procedures can be adopted following a full characterization of a particular situation but that it is extremely unwise to select a single normalizing element and assume it will serve the purpose in a new situation simply because it did elsewhere. Recognizing the topical concerns over algal blooms 161