Development of a monitoring network of water resources in urban areas as a support for municipal environmental management

Abstract

Water resources in urban areas are often impacted by the intense land use in the cities. The development of a surface water monitoring network is a critical element of water resource sustainable management. The city of Caxias do Sul is the second largest metal mechanic industrial region in Brazil. Industrialization seriously impacts river water quality and is a challenge to public authority supervision. The development of a water monitoring network was the solution public authorities found for the municipality environmental management. The network included 12 stations, monitored over 13 months for 15 physical and chemical water quality parameters. Stations were placed according to maps and satellite images, so as to identify the contributing watershed and land use. Principal component analysis (PCA) was one of the techniques used for data analysis. The first principal component corresponded to the variation of total nitrogen, ammonia, total phosphorus, BOD, COD and electrical conductivity and responded for 76.54% of data variance. The variables that comprised the first component indicated that the main source of water contamination was domestic sewage. The second principal component was composed of chromium, nickel and zinc, suggesting sewage discharge from electroplating industries. The third principal component presented aluminum and iron that are naturally found in local soils. The concentrations of such parameters in each monitoring station

Re-Thinking Urban Flood Management—Time for a Regime Shift

“…Continuous urbanization will result in increasing nutrient and contaminant emissions of watersheds, putting human health and ecosystems in danger [44,45]. Due to the absence of trans-scale thinking, drainage and flood protection systems mostly rely on expensive and inflexible underground solutions.…”

Use of water quality index as a tool for urban water resources management

“…The objective was to give support to the monitoring process and assessment of the water quality of the water resources in the urban area. The conception of the monitoring network and its characteristics were presented by Finotti et al [1]. The monitoring network comprised 12 sampling stations, in which the flow rate and 20 water quality parameters were examined.…”

“…As the amount of data from the network was too large, the principal components analysis (PCA) was applied to indicate which quality parameters would better represent the dataset under analysis. Finotti et al [1] describe in details the results of application of PCA. These results, which are briefly presented in the results section hereof, were used as a support for the calculation of the quality index, as described below.…”

“…Public authorities of Caxias do Sul implemented the monitoring network, comprising 12 stations monitored monthly for 20 water quality parameters and flow rate. Results from this study are compared with the first year of monitoring [1]. The NSF-Cetesb WQI and the CCME WQI were calculated and the results are compared with the municipal environmental management and water resources management.…”

“…Such mechanisms include the implementation of monitoring networks, through which samples are collected periodically for determination of physicochemical, physical and microbiological parameters. Monitoring networks can be excellent management tools of environmental and water resources, as shown by Finotti et al [1]. The results should be assessed periodically.…”