Secondary iron ion contamination of water in the water supply network

Abstract

This paper presents the modeling of iron concentration in the water supply network using geo-graphic information systems. The method of ordinary cokriging, which belongs to geostatistical methods of data interpolation, was chosen to estimate the distribution of variation of iron content in the water supply network area. Actual values of iron concentration in tap water were used for the modeling. The tests presents the results of estimating the values of estimated iron ion concentrations over a year. Data input in the model regarded the existing water supply network adminis-tered by the Municipal Water Supply and Sewerage Company in the Capital City of Warsaw, Joint Stock Company. Advanced technologies and modern water treatment processes are in many cases insufficient to deliver high quality water to the consumer. The composition of water in a water supply system is altered by physical, chemical and biological processes. Phenomena occurring in water supply networks, plants and equipment cause deterioration of water quality at the stage of water distribution. The results of laboratory tests on the quality of water entering the water supply network from the three water treatment plants and water supply network with control points were pre-sented. The test results showed different concentrations of iron ions in the water supply network control points within the range from 0.012 to 0.85 mg/L. Results of spatial distributions of secondary iron contamination using ordinary cokriging method on the infrastructure map was able to determine the places of iron concentration changes in the water supply network.