Presenter: Michael Harmon, College of Science, Engineering, and Technology, Physical Sciences
Authors: Michael Harmon
Faculty Advisor: Trevor Terrill, College of Science, Engineering, and Technology, Physical Sciences
Institution: Dixie State University
Nutrient and health monitoring in water is important for agriculture, fishkeeping, municipal water, and other applications. While many parameters are quick and easy to obtain, determination of nitrate levels is surprisingly difficult. Accurate nitrate readings help prevent over fertilization, ensures proper nutrient levels for plant growth, monitors living conditions for fish, and helps ensure safe drinking levels. Current nitrate monitoring methods require sample collection, extensive preparation, expensive equipment, and lengthy processes that require domain expertise. The goal of this project is to test a novel approach to nitrate testing to affordably, reliably, and constantly monitor nitrate levels in any desired flow or body of water. This is accomplished by using low-cost LED’s of known wavelengths that are absorbed by nitrates. The LEDs shine through water in a quartz cuvette. A photo-sensor on the opposite side detects the intensity of light, which is used to approximate nitrate levels present in the water. A similar approach has been found in the literature for soil nitrate monitoring; however, these studies are limited, and the approach has not yet been attempted for water nitrate determination. This device will make constant monitoring of water in almost every application simple and cost effective, and can give instant feedback on nitrate issues in water. This can potentially aid farmers, aquarium hobbyists, and others by providing a portable solution that can prevent costly issues of toxic fish environments, unhealthy water, and excessive fertilization. In the future, this sensor could be seamlessly integrated into existing constant-monitoring devices for other common water parameters, such as pH, dissolved oxygen, and ammonia.