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This paper presents the linkage between geomorphologic characteristics of the relief, tectonic structures, lithologic composition of deposits on the Krk island, and the degree of natural hazard and geotechnical risk. The influence of geotechnical risk on the physical planning is analysed, as well as the experiences and construction defaults in some urban locations. All rocks and soils on the Krk island in form three specific types of ground with different lithological composition and geotechnical properties and therefore quite different geohazard degree. They are: karst area, flysch area and alluvial area. Generally speaking, karst area is the most favourable for constructing, because has the lowest degree of geohazard, but this type of ground also comprises a great number of sites which are less favourable for construction. Flysch area has the higher degree of geohazard than karst area. Some geotechnical very favourable sites are situated on flysch type of ground. However, on these sites the old towns are located with lesser possibility for theirs expansion. Alluvial areas are greatly covered by the agricultural land and therefore they are inadequate for urbanisation.

The city of Osijek has a combined sewage system. The basic sewage system, constructed at the beginning of this century, is still functioning. With the development of the city, and the increase of the number of citizens and industry, a secondary sewage system was being built accordingly, but this has not been followed with the same intensity by a primary sewage system. The wastewater coming from the city of Osijek and neighbouring urban areas together with the industry wastewater is being discharged into the river Drava without being previously treated. This is causing a significant pollution, worsening the river water quality so that it does not meet the class II. criteria. The fact that the pollution condition of the river Drava is quite serious is causing an urgent need to solve the problem of city wastewater treatment, together with its neighbouring urban areas. The assumption for the previous is the necessity to build the primary sewage system completely. Also, the quality and quantity of wastewater of the city and industry must be known, but with regard to the previous war and recession in the industry, the problem of prognosticating these magnitudes with enough certainty is existent. This paper shows the results of analysis Osijek’ s wastewater, and also points out some problems with regard to the necessity of constructing a wastewater treatment plant.

Development of the Krk Island (channel part of the Adriatic Sea) so far has managed to perserve the major part of the area in its natural condition. Major damages were sustained only in the northern part of the island where industrial facilities were built. Island of Krk is situated along a favourable geographical and traffic direction, so future period foresees development and construction of additional industrial fasilites and tourist capacities. This will inevitably cause the increase in population and number of consumers . This work analyzes water supply in given conditions, as well as the relation between the existing reserves and required potable water quantities. The Cretaceous and Paleogene carbonate rocks (limestones, intercalated limestones and dolomites and breccias) dominate in the terrestrial part of the island of Krk, whereas Paleogene flysch is limited.The carbonate rocks are karstificated -70 m below the recent sea level and have good permeability. For this reason, carbonate rocks, contain the major part of underground water. Flysch rocks are impermeable and have a role of hydrogeologic barriers.Regarding the fact the tectonic structures were not completely investigated, the spreading of aquifers and total groundwatter reserve are not entirely known.Because of well degree of permeability, groundwater protection on the karstic area is difficult.Another problem is possible connections between marine salt water and groundwater aquifers.On the basis of such soil structure, this work analyzes possible detrimental influences on underground water quality, as well as protection direction. It also analyses the impact of underground water protection on development of particular parts of the island. Sum analysis gives sustainable development of the Krk Island.

This paper describes the origins and development of organized water management in the Karašica and Vučica watershed. The perceived water problems initiate and determine elements (line of procedures - directions) of farther development. The influence of general social situation on the relationship towards water is stressed. The significance of observation activities for functioning and development of hydro-system is established. Agricultural production improvement through the hydro-system of the Karašica and Vučica rivers watershed is critically considered from this aspect. The paper concludes that in the development of the considered system, and all other systems too, a period of necessary changes is to be expected.

The ship landing stage of Slavonski Brod at the left bank of river Sava will be constructed as reinforced concrete structure. Due to heavy live loads, it is important to consider the serviceability limit state of structural elements. Separate methods for calculation of curvatures and method for calculation of curvatures are described. Besides deflection, which can be calculated for certain load, the dependence of deflection on increased load could be determined as well, and showed in form of diagram. It is possible to determine not only maximum value of deflection, but value of deflection in any point along the girder and at any value of load as well. The results of calculated deflections of structural reinforced concrete beams, of port in Slavonski Brod, are presented.

The example of river quay that will be constructed as reinforced concrete structure is presented. Quay on river Sava at Slavonski Brod will consist of space structure whose elements will be beams, columns, walls and slabs. All the structure will be supported by geotechnical piles. Some reinforced concrete elements such as girders and thin plates will be prefabricated, while columns, walls and slabs will be cast in place. Various loading cases such as dead and live load, water level loading, railway- and mobile-crane load, wind on crane, railway loadings, containers, ship impact forces, wawes, earth pressure, seismic loadings etc. shall be used in analysis. Due to durability reasons the structure elements will be of simple shape and robust.

This paper gives a brief review of the development and functioning of protection system from the harmful activities of waters in the Karašica and Vučica river basin. It gives the retrospection on the adopted concept for drainage security that used retention at first and later then multipurpose accumulation. Here are examined the development circumstances of accumulation Lapovac II , which is the only accumulation made in the mountain part. The parameters of this accumulation are mentioned and its use is described. The effects of its work are analysed. The defectiveness of the present monitoring for better and high-quality evaluation is observed. It can be concluded that the accumualtion achieved its purposes. The huge mountain waters were successfully accepted even by precipitation of over 150 l/m2 so that the flood of downstream area was prevented. Over 50 % of planned potention for watersupply was used. The development of some sport-recreation and ecological facilities overdid all expectations.