This Small Business Innovation Research (SBIR) Phase I project aims to develop a novel chemical sensor technology for inline water quality monitoring. Currently, gas chromatography coupled mass spectroscopy is the most widely used technique for water quality analysis; however, the method is costly, time consuming, and can only be performed by well-trained personnel in a laboratory setting. To meet the market need for a portable, low-cost, and easy-to-use water analysis technology, the project will investigate a photonic sensor platform which resolves the aforementioned challenges through: 1) the development of a compact photonic sensor package consisting of an optical resonator sensor chip, a laser source, and battery power for standalone operation and field deployment; 2) the application of molecularly imprinted polymers as robust sensor coatings for highly selective molecular detection in a non-laboratory setting; and 3) the use of a pattern recognition algorithm to automatically detect and quantify individual component concentrations in a mixture.<br/><br/>The broader impact/commercial potential of this project is a portable, low-cost sensor product which meets the needs from the water quality monitoring market, a growing sector with a compounded annual growth rate of 4.6%. The implementation of chlorination disinfection systems has virtually eliminated waterborne diseases in the United States. However, disinfection byproducts pose different health risks, including reproductive endpoints, developmental defects, and cancer. If successful, the proposed sensor technology will eliminate/minimize the adverse human health effects caused by those chlorination disinfection byproducts by providing real-time water quality information. According to a recently released market research report, the global water analysis instrumentation market is projected to be $1.86 billion by 2017 with the online systems for water analysis instrumentation being predicted as the fastest growing market segment. A major limiting factor that prevents a wide market acceptance and penetration of existing online water monitoring devices is the relatively high investments involved. The proposed sensor implements the online water quality monitoring functions with mass-producible and inexpensive optical sensor elements and reusable sensor coatings. Consequently, successful demonstrations of the proposed sensor technology can facilitate a wider market acceptance and penetration of the online water quality monitoring devices.