E3S Web of Conferences, open access proceedings in environment, energy and earth sciences

Urban regeneration as a complex project, generates many extremely specific threats affecting the increase of investment risk. Its unique nature causes that probability parameter, normally applied in the process of risk quantification, is extremely difficult to estimate. Due to lack of historical data urban regeneration related activities are therefore associated with uncertainty. According to the authors, a useful tool for resolving the above issues may prove to be Bayesian networks (BN). Beliefs based on expert knowledge should be considered as a subjective measure, nevertheless BN also allow to combine this information with objective results of conducted research. The authors built a model representing various urban regeneration risk areas, where the analysis covers degradation of the urban regeneration area. The article also presents selected parameters allowing for diagnostics of technical condition of buildings, road pavement and underground infrastructure in the area of urban regeneration.

This paper indicates and analyses the use of anchoring systems, such as mooring piles, booms, mooring cables, and deadweight anchors with additional elastic connectors, which are the most frequently applied by the producers of floating houses. The selection of the most advantageous anchoring system is complicated and requires the application of quantitative and qualitative data and methods. This publication presents the results of the calculations using one of the most common methods of multi-criteria analysis of decision-making, namely AHP (analytic hierarchy process). The anchoring system, which is the most beneficial for users, has been indicated with the use of the main criteria such as: cost, time, external risk factors, geospatial factors, and the sub-criteria of the first and second order. Due to the conducted analysis, it has been shown that the most significant factor of the anchoring system selection for the users of floating houses is the investment cost that needs to be borne during the usage, and the most favourable anchoring system is the use of mooring cables.

The aim of the article is to identify factors that determine the development and management models of floating housing development in the analyzed countries. The author indicates factors determining the possibility of settling on bodies of water in Poland, and restrictions connected with this type of development, as well as the need for specialized persons and companies ready to meet the challenges of the modern management of hydro-technical facilities, including floating housing development. In Western Europe, living on water is gaining in popularity. People have begun to dwell on water because of rising land prices, congestion in cities and work related to the use of rivers for the transport of goods. The popularity of housing on water in the Netherlands results from environmental conditions. About 60% of the Netherlands is below the sea level. For hundreds of years, the population of the Netherlands has been battling with the elements, while being exposed to continuously rising sea levels, which has been a consequence of the greenhouse effect. Environmental changes have caused a change in government policy, which began to support construction activity on water, adapted regulations and changed office holders. In North America, especially in the United States, the identification of residents with their neighborhoods of houses on water is so high that it has resulted in the formation of communities uniting owners of residential watercrafts, who have succeeded in homes on water becoming recognized as real estate and, consequently, now have the same rights as residents of houses on land. In Poland, housing estates on water are slowly gaining popularity but no factors determining the development of this type of settlement have been established. An analysis of the situation in Poland reveals many factors limiting the functional use of houses on water and a lack of specialists in the management of hydro-technical facilities. Therefore, on the basis of examples of countries in Western Europe and North America given in this article, the author tries to define the responsibilities of managers and an appropriate management model for housing estates on water in Poland, as well as indicate problems with the development of housing on water and their possible solutions.

Each investment plan, including the one concerning a building, is exposed to the consequences of various types of threats taking place. Therefore, in the case of some large-scale, atypical and complicated building ventures, some actions included in the procedure of risk management should be taken (identifications, analysis, measurements, control and supervision of the risk). This will allow for the risk to be eliminated or limited. While preparing a building venture, an investor does not possess full information about the course of events on each stage of investment completion. The identification of the above-mentioned unknowns, subjecting them to quantification and specifying the method of dealing with them, allows an investor to increase the effectiveness of the intended plan. The enterprise discussed in this article and analyzed in the context of risk, concerns alteration, revitalization and conversion for office purposes of two buildings located in Gdańsk at 1 and 2 Lastadia Street. These buildings are situated on the area of historical urban layout of Gdańsk, in the northern-eastern part of Stare Przedmieście District (Old Suburb), about 800 meters south from Dlugi Targ Street and 200 meters west from The Old Motława River. The investor is "Gdańskie Melioracje Ltd.", a limited liability company, which belongs to the Council of Gdańsk. In order to increase the effectiveness of the intended investment venture, while organizing the investment process, the investor commissioned preparation of an analysis and risk evaluation connected with the above-mentioned intention. Based on an on-site visit, the opinions of experts, who have been involved in the process of the preparation of the investment, studies of the available monographies about the technical condition of the buildings at 1 and 2 Lastadia Street and their own experiences, the authors identified 54 types of relevant risks, which have been systematized into 10 subject groups (among others- investor's risk due to the designing process, location of the investment, third party or investor business activity, force majeure, political, legal, financial, technical). The scope of the study includes the identification, analysis and risk evaluation connected with planning and completion of alteration, revitalization and conversion of a historic building located at 2 Lastadia Street for the office purposes. The risk has been analyzed from the investor's perspective. The authors used a method of preliminary analysis and risk evaluation PHA (Preliminary Hazard Analysis) and the expert method.