Bacterial contamination of water is a global problem. Harmful bacteria in drinking water can cause diseases such as diarrhea, cholera and typhoid fever, leading to millions of deaths every year. In addition, microbial growth in industrial water systems can result in biofilm formation (biofouling) and microbiologically induced corrosion (MIC) within pipelines and storage tanks, requiring enormous effort and cost to repair. Rapid methods are needed to give users the ability to detect and mitigate problems before they can lead to costly downtime. ATP assays, performed in a lab or other formats, are an easy way to regularly monitor water systems and measure effectiveness of antimicrobial treatments.