There is a growing need for low cost, remote sensing systems which can be deployed in situ in sufficiently large numbers to ensure that data on key water quality parameters is readily available. The challenges facing this ideal of monitoring include the cost of these platforms and the inability to “deploy and forget” due to limited long term stability and maintenance requirements. Microfluidic technology has great potential as a solution to the increasing demand for environmental monitoring, by producing autonomous chemical sensing platforms at a price level that creates a significant impact on the existing market. The development of sensing platforms for ammonia and nitrate in water and wastewater are being investigated. Our approach is to combine microfluidics with simplified colorimetric chemical assays; low cost LED/photodiode-based optical detection systems; and wireless communications. In order to drive down the cost of these devices, it is vital to keep the fluidic handling requirement as simple as possible, as multistage methods are expensive to implement as well as being less reliable in long-term deployments. Colorimetric methods for nitrate and ammonia have been modified eliminating several steps previously associated with the methods to facilitate their implementation into an autonomous platform, resulting in a rapid and simple measurement procedure.