Luis Neumann

Adapting to climate change through urban water management: a participatory case study in Indonesia

The benefits of integrated approaches to climate risk and adaptation studies are increasingly recognised. Thus, there is an increasing need for practical examples of such work in the literature. This paper describes a practical application of an integrated framework for climate change impacts on regional surface water resources and the urban water system in the Mamminasata metropolitan region, Indonesia. Two main features of the framework are: the integration of both climate and other physical and social considerations in the assessment; and the high stakeholder involvement before, during and after project implementation. Although the study is concerned with the Mamminasata region, the overall methodology is transferable to any region in Indonesia or internationally. Key outcomes from this study are: (1) creation of information for Mamminasata planners and water resources managers for when, and under what conditions, the water supply may or may not meet the demand; (2) a clear consensus and shared learning of the problems facing the region among cross-institutional stakeholders; and (3) identification of adaptation options for the urban water system and knowledge gaps and strategies for their implementation. Results of stakeholders’ surveys conducted at the mid-point and at the end of the study indicate that these outputs will provide valuable guidance for future planning and management of Mamminasata regional water resources.

Water use, sanitation and health in a fragmented urban water system: case study and household survey

In a study to identify strategies to deal with rapid urbanization and threatening climate change, in Can Tho City, Vietnam, a survey of 1200 households was undertaken to investigate water access and sanitation services. The survey targeted three different groups based on their access to water services: (a) those with piped water supply, (b) without piped water, and (c) a mix of (a) and (b). Socio-economic factors and level of urbanization significantly influenced the different water sources accessed by households and their type of sanitation. Results indicated that householders often employed multiple water sources in an attempt to match source with intended use. The use of multiple water sources, levels of sanitation and the quality of water were found to be good indicators of reported rates of illness. Results also showed that the provision of piped water does not always provide the desired health outcomes, as the definition of adequate water supply does not include water quality objectives. Therefore, more detailed assessments may be required to understand how people use and access water and sanitation, and the impacts on public health.

Spatial GR4J conceptualization of the Tamor glaciated alpine catchment in Eastern Nepal: evaluation of GR4JSG against streamflow and MODIS snow extent

Snow and glacial melt processes are an important part of the Himalayan water balance. Correct quantification of melt runoff processes is necessary to understand the regions vulnerability to climate change. This paper describes in detail an application of conceptual GR4J hydrological model in the Tamor catchment in Eastern Nepal using typical elevation band and degree-day factor approaches to model Himalayan snow and glacial melt processes. The model aims to provide a simple model that meets most water planning applications. The paper contributes a model conceptualization (GR4JSG) that enables coarse evaluation of modelled snow extents against remotely sensed Moderate Resolution Imaging Spectroradiometer snow extent. Novel aspects include the glacial store in GR4JSG and examination of how the parameters controlling snow and glacial stores correlate with existing parameters of GR4J. The model is calibrated using a Bayesian Monte Carlo Markov Chain method against observed streamflow for one glaciated catchment with reliable data. Evaluation of the modelled streamflow with observed streamflow gave Nash Sutcliffe Efficiency of 0.88 and Percent Bias of <4%. Comparison of the modelled snow extents with Moderate Resolution Imaging Spectroradiometer gave R2 of 0.46, with calibration against streamflow only. The contribution of melt runoff to total discharge from the catchment is 14–16% across different experiments. The model is highly sensitive to rainfall and temperature data, which suffer from known problems and biases, for example because of stations being located predominantly in valleys and at lower elevations. Testing of the model in other Himalayan catchments may reveal additional limitations.