Tensions in water management: Dutch tradition and European policy.

Present-day worldwide water problems require new management tools and sustainable system innovations. At Delft University of Technology research is being carried out into water resources and management development aimed at forming such tools and innovations, focused on Integrated River Basin Management (IRBM). One of the case-studies deals with Dutch water management and technology in the context of European IRBM in the form of the 2000 Water Frame Directive. The Netherlands experience many water problems and European IRBM could bring help by offering a framework for both international cooperation and technological innovations. To work as an adequate management tool European IRBM should be tailored to the Dutch water tradition, which recently culminated in Integrated Water Management. Both approaches are in some respects contradicting. Europe pursues, for example, centralized control; while the Dutch have their strongly water boards based decentralized administration. The tensions between both approaches require mutual adaptation, for which the concept of subsidiarity might offer points of departure. This paper describes the first results of the case-research into Dutch water management and technology in the context of Europe as well as the backgrounds and the set-up of the research as a whole.     

Time Series Concepts for Conditional Distributions*

The paper asks the question – as time series analysis moves from consideration of conditional mean values and variances to unconditional distributions, do some of the familiar concepts devised for the first two moments continue to be helpful in the more general area? Most seem to generalize fairly easy, such as the concepts of breaks, seasonality, trends and regime switching. Forecasting is more difficult, as forecasts become distributions, as do forecast errors. Persistence can be defined and also common factors by using the idea of a copula. Aggregation is more difficult but causality and controllability can be defined. The study of the time series of quantiles becomes more relevant.     

Effects of soil erosion on water quality and water uses in the upper Phong watershed.

The main objective of this paper is to simulate the effects of soil erosion on river water quality and on agricultural production as a result of the transformation of forestlands in the catchment of the upstream Phong River. Suspended solids carry down attached nutrients and agricultural chemicals causing water pollution in the downstream. There are four different types of land use in this simulation, namely forestlands, flatland and highland sugarcane plantation areas, and paddy fields. The highest mean annual amount of soil erosion is from paddy fields (585,700 tons/year), followed by highland (73,800 tons/year) and flatland (63,950 tons/year) sugarcane plantation areas and forestlands (41,800 tons/year), respectively. However, as most of paddy fields are located in a low land and are wet type cultivations, the soil erosion occurred has less impact on river water quality and its production compared to the soil erosion from the steeper slopes of highland plantation areas. Under the resource-based agriculture, the sugarcane production is mainly increased by expanding the plantation areas leading to a significant loss of topsoil and a considerable reduction of agricultural production. Soil erosion contributes to an increase in the average annual suspended solids concentration by 72 mg/l.     

UNIT MANAGEMENT BUYOUTS, STOCKHOLDER WEALTH, AND SELLING FIRMS' CHARACTERISTICS

Previous research on unit management buyouts, UMBs, has shown that selling firms benefit from the selloff transaction. The current research demonstrates that when the selling firm has either poor liquidity or poor earnings, selling firm shareholders do not benefit as much. We hypothesize that the unit managers have knowledge about the selling firm's difficulties so they do not pay as large a premium for the assets. Since the unit managers technically are employed by the selling firm shareholders, their bargaining to achieve a better price is an agency cost. Finally, selloff frequency does not affect seller abnormal returns.     

The local economic impact of construction projects in a small and relatively self-contained economy: The case of Lancaster University

Whilst the local multiplier impacts of the annual operation of universities has been the subject of intensive research, the economic impacts of capital construction projects have been almost completely ignored. This paper presents the results of detailed analysis of capital projects at Lancaster University in 1993-The reasons for the radically different annual operation and construction multipliers estimated in the Lancaster study are examined. Despite the smaller size of construction multipliers it is argued that it is a serious mistake to estimate local construction multipliers by making simplifying assumptions on the size of the key parameters in the multiplier equations.     

Implementation of sustainable sanitation in existing urban areas: long-term strategies for an optimised solution.

If technologies for decentralised sanitation and reuse (DESAR) and for natural stormwater management should at least partially replace existing systems, then intensive reconstruction work becomes essential. A conversion can only be realised successively over a long period due to high construction and financial expenses and requires new strategies. This paper presents the development and practical implementation of a mathematical tool to find an optimised strategy for the realisation of alternative and more decentralised drainage and sanitation concepts in existing urban areas. The succession of construction measures (e.g. the implementation of decentralised greywater recycling) for the whole period of consideration is determined based upon a mathematical optimisation model on the condition that the favoured future state is known. The model describes the complex interdependencies of the urban water and nutrient cycle and enables the minimisation of both financial efforts and ecological impacts on the way toward the future state. The results of the implementation for a rural area in Germany show that the mathematical optimisation is an adequate instrument to support decision-making processes in finding strategies for the realisation of sustainable urban water management.     

Possibility of sewage and combined sewer overflow reuse with biological aerated filters.

The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions.