Hidrológiai Közlöny 1974 (54. évfolyam)

3-4. szám - Könyvismertetés

Hidrológiai Közlöny 1974. 3—4. sz. 138 The position and role of designing in water management By ISTVÁN GYÖRGY, CiV. Engr. Director, Institute for Hydraulic Planning (V1ZITERV) The objectives and tasks with which we are faced in connection with the contemplated water management projects have been described in the foregoing, together with the perspective planning activities conducted in this sector. It is desirable hereafter to define the position of designing within the national system of water management. Perspective planning in water management defines the projects to be realized in the future in accordance with the decisions of perspective economic palicy. These projects are studied for economic desirability and the main specifications of the technically feasible alternatives are determined. Designing has the responsibility of elaborating the economic and technical indices required for taking decisions on individual projects, as well as the engineering solutions of constructional measures included in the perspective plans and envisaged in the medium-range plans. Subsequently the construction drawings of the project, or project system are prepared by the designers. The first stage in designing involves thus the elaboration of the general arrangement and drawings of the contemplated project to such depth as is needed for estimating the engineering and economic parameters thereof. This is referred to in Hungary as the investment project programme. In formulating this programme allowance must be made for the basic aspects of water management as outlined in the perspective development plan of water management. These are defined in the water management policy prepared by the National Commission for Technical Development and approved by the Government in January, 1973. The designer is obliged to take into consideration: — the results of research and observations available for the solution, — the standard of technical-technological equipment available, together with the possibilities of purchasing them on the domestic, of foreign market, — the possibilities of the building industry and the technological level of the construction industry available at the time of project realization, finally — the organizational and economic criteria for safe; reliable and economic operation. Once a decision is taken on the basis of the indices elaborated in the project programme, the construction drawings are prepared. In Hungary this is mostly the responsibility of state designing enterprises, while abroad this is performed in many instances by the contractor of construction, or technological mounting work, or else by the general contractor. The construction drawings for major projects are invariably prepared by one of the few designing enterprises with large staffs, whereas those for projects of local importance, by designing offices at councils, associations, or cooperatives. In the domain of water management, two designing enterprises operate under the guidance of the National Water Authority, but several enterprises belonging to the Ministry of Building and other departments are engaged, beyond their main functions, in designing water supply and sewerage works. Some designing activity, substantially lower in volume, is carried out by the minor designing groups of the district water authorities and by the water associations. The projects affected are substantially of local significance and call for a modest engineering standard. During the past two decades — the designing enterprise in the water sector, namely VIZITERV, has been founded 20 years ago — the conditions of planning and designing in the water sector have undergone fundamental changes both in Hungary and abroad. Following the establishment of an integrated water management organization, a uniform system of water administration has evolved in the country and the projects designed must completely fit into this integrated pattern. — Formerly individual structures, or projects were generally built in the domain of water management. These have been replaced during these 20 years by complex, multi-purpose projects. — Management of water resources has become better organized. The limited supply of water has made the introduction of conservation practices necessary. — Industrial production has increased considerably in volume. In Hungary this increase was three-fold during the past 20 years. The fresh-water demand of industry increased accordingly. Whereas in 1953 it was 3.5, by 1973 it attained 9.5 million cu.m/day. The recycled water demand of industry was 17 million cu.m/day in this year. —• The living standard of the population must be increased at a higher rate. Services must be improved, which entails a higher domestic water demand. The proportion of population served by communal water supply was 30% in 1953 and 50% in 1973. The sewage production at settlements doubled in volume as a consequence. — The number of polluting sources increased considerably, the use of chemicals in agriculture resulted in increased pollution in both surface- and groundwaters, so that the demand for pollution control became more urgent. — Labour has become scarce, so that mechanization and automation is increasingly necessary in the projects realized. — Technology has advanced greatly. New construction methods and equipment call for a new technological standard, but make more economical solutions possible. All these changes have made the work of designers, substantially more complex, and havé introduced the demand for increasing specialization. This situation is illustrated by considering the evolution in the field of domestic- and industrial water supply. — In the past drinking water was obtained exclusively from groundwater, whereas now increasing use is made of artificial reservoirs, or other surface sources. — Isolated water works were constructed for plants, villages and towns. Now regional water works are comman, supplying water to the settlements in the area involved from an integrated distribution system. — The rapid evolution of recreation and tourist trade has resulted in the development of recreation centers (Lake Balaton, Lake Velence, Danube Bend, etc.), the seasonal character of which (summer, or week-end peaks) presents special problems to the designer. These changes have presented new problems and promoted the development of new technologies in the fields of water production, treatment and distribution (e.g. groundwater recharging, subsurface storage, new and high-efficiency clarification processes, multi-layer filters, active-carbon treatment, new de-ironing and de-manganizing procedures, large-scale development of control engineering and automation). Second-stage biological treatment was at the most applied to wastewaters. Biological treatment has become by now essential, and even advanced tertiary treatment is desirable, providing sludge conditioning and sludge disposal. New pollutants are encountered, especially in the