Every year water-borne bacteria cause millions of infections in humans and animals. Current bacteria detection methods are slow or expensive. The standard plate count, takes from 24 to 48 hours, due to the time needed for bacteria to grow detectable colonies. This time is too long for most applications. Faster methods, including PCR or labeled detection and fluorescent imaging, are too expensive to be widely applied. Here we present a proof of concept of miniaturized and fast bacteria detection device. Using dielectrophoresis, the device automatically separates any present bacteria from a water sample. For detection the devices uses nanoribbon/nanowire field effect transistors, which are demonstrated label-free nanosensors, capable of detecting low concentrations of biomolecules, i.e., disease markers to provide point-of-care diagnostics. In order to achieve selectivity and specificity of the detection and eliminate false-positive responses, the sensors are functionalized with bacteria specific antibodies.