Cloud computing paradigm is gaining more and more momentum, to the extent that it is no more confined to its initial application domains, i.e. use by enterprises and businesses willing to lower costs or to increase computing capacity in a flexible manner. In particular, increasing interest is recently being paid to the huge potentials – in terms of benefits for the society at large – that might result from the adoption of cloud computing technology by critical infrastructure (CI) operators. This is of course putting special emphasis on the need for dependable and trustworthy security mechanisms in cloud technology based services, since a critical infrastructure is vital for essential functioning of a country. Incidental or deliberate damages to a CI have serious impacts on the economy, and possibly make essential services unavailable to the communities it serves. In this paper we present the proof-of concept of a cloud-based Water Supply Network Monitoring (WSNM) application, named RiskBuster (RB), that ensures the confidentiality and integrity of SCADA monitoring data collected from dam sensors and stored in the cloud by using the innovative Intel Software Guard eXtension (SGX) technology.