Risk Mapping of Water Supply and Sanitary Sewage Systems in a City in the Brazilian Semi-Arid Region Using GIS-MCDA

Abstract

It is essential to visualize water scarcity as a result of an inappropriate process of appropriation and the use of natural resources. This understanding has been gaining more and more prominence in studies in Brazil and also in the world. In this context, this research aims to map the risk of water shortages and sewage insufficiency in a Brazilian semi-arid city using GIS-MCDA. The secondary data used in this research were collected from IBGE, Compesa, and the City Hall of Caruaru and were processed using the QGIS 3.12 Bucareşti software. The Pernambuco Tridimensional database and the Analytical Hierarchy Process method were used in the process to generate the maps. After collecting and analyzing the data, it was seen that, according to the water shortage risk map, seven neighborhoods had a “Very high” risk, in which the criteria with the greatest weight were the distance from distribution reservoirs, the main supply network and altimetry. The map of the degree of sanitary sewage insufficiency showed that four neighborhoods have a “Very high” degree; these neighborhoods are far from the main sewage network and from sewage treatment stations and have the lowest rates of households served by the system. Such characteristics need to be highlighted in the planning and implementation of water and sewage services. Thus, it is concluded that the use of high-resolution spatial databases for the planning of urban services, as carried out in the present work, provides a greater level of confidence for solutions that can be implemented in the expansion of service networks to the population.

Decision Support System for the Integrated Management of Multiple Supply Systems in the Brazilian Semiarid Region

“…It can be seen that most demands are low, with the municipality of Caruaru having the highest demand, equivalent to 1.130 m 3 /s, but the average for the study area is only 0.107 m 3 /s. Without the use of multiple water sources, the municipality of Caruaru is subject to significant water rationing, driven mainly by the lack of rain, the deficiency in water distribution and the higher demand required, as highlighted by Silva et al [31]. It was possible to notice that most consumption centers categorized as villages and, therefore, with very low demands, have higher unit costs, as is the case of Alto São Francisco, Vila de Santana and Vitorino.…”

An Evaluation of Possible Sugarcane Plantations Expansion Areas in Lamongan, East Java, Indonesia

“…The final weight of the land suitability analysis was the total of the weighted results of the criteria with ANP multiplied by the score of each sub-criteria [46][47][48]. The largest final value indicated the most suitable class.…”

Implementation of User-Oriented Geovisualization Web Dashboard for Monitoring Access to Improved Water using Satellite Imageries Data

“…The MCDA method produces an index that can describe access to improved water, called the improved water access index (IWAI). IWAI is an updated version of Water Shortages Risk (WSR) [18] and Risk of Water Shortages (RWS) [17]. WSR and RWS only measure the risk of water shortages to provide tap water for urban water supply systems (UWSS), meanwhile, IWAI can measure the vulnerability of access to improved water.…”

“…Due to its rural and mountainous terrain, which is far from any infrastructure for piping in water, it is obvious that the area has limited access to improved water. Pipeline water distribution to highlands, especially in areas far from water treatment facilities, is very difficult because it requires a lot of money and effort [17], [18]. Users may be interested in monitoring particular locations when monitoring.…”