This Small Business Innovation Research (SBIR) Phase I project will use a moisture sensor to monitor moisture ingress, corrosion, and delamination of fiber-reinforced polymer (FRP) concrete structures. Phase I will build on the development of a moisture sensor for composite aircraft and adapt its use for infrastructure such as bridges. FRP is increasingly being used to reinforce such structures during rehabilitation, but uncertainties concerning the health of the composite and the bond between the composite and the concrete prevent widespread application. The moisture sensor, which is based on the established technique of electrochemical impedance spectroscopy (EIS), will allow moisture intrusion and the effects of moisture to be tracked from very early stages. <br/><br/>Initial commercial applications will involve an inspector using a portable computer to interrogate the sensors to determine structural health. The advanced application would include a permanently mounted potentiostat module that would periodically send signals to a central location. Commercial opportunities include over100,000 structurally deficient bridges that are candidates for FRP rehabilitation.