ABSTRACT
Integrated Urban Water Management should be based on true, measured data, with assessed uncertainties (as discussed in Chapter 6). Monitoring equipment, specially designed for the measurement of certain parameter(s), is used to obtain such data. A number of monitoring devices are available on the market and the task of optimal design and equipment selection is therefore not easy. Selection of monitoring equipment is typically made subsequent to the establishment of the goals and objectives of the monitoring programme (Chapter 3). The selected equipment has to not only fit the purpose, but the available budget, desired precision and accuracy and appropriate scale (e.g. a turbidity sensor used in a drinking water reservoir will need to be optimized to a different scale than, say, one used at the inlet of a wastewater treatment plant). It also has to cope with spatial variability of the measured variable (Chapter 5), to work within on-site environmental conditions, to work continuously between inspection and maintenance periods and to be able to be readily (and reliably) calibrated under field conditions. Relevant government laws and contract agreements should also be checked for possible selection constraints. Contract agreements for the purchase of measuring devices often dictate required measurement systems. These constraints may be in terms of accuracy, specific comparison of devices and procedures.
