Balloon Platforms for Remote Sensing of Water Quality in Mixing Zones

We hypothesize that infrared (IR) cameras mounted on unmanned tethered helium balloons accessed via a wireless network can remotely sense water quality in mixing zones at site scales. Mixing zones are limited regions in water bodies where the initial dilution of point-source wastewater discharge occurs. Mixing zones are an important component of the National Pollution Discharge Elimination System (NPDES) permitting process within Total Maximum Daily Load (TMDL) water quality management programs. In Phase 1 MixZone developed a low cost, rapidly deployable, aerial remote sensing system for monitoring water quality in riverine mixing zones. Our patent pending platform monitors outfall performance and focuses on temperature as a dilution tracer. In cooperation with EPA Region 10 and Oregon DEQ, we successfully field demonstrated our system at an industrial discharge site. We proved the technical feasibility of our remote sensing concept to gather continuous, real time, site scale, geo-reference mixing zone data for NPDES regulatory compliance and ESA habitat assessment. Alternative aerial remote sensing platforms have limited availability, high costs, and long lead times to schedule deployment. The cost of our platform will be 1/3 to 1/10 of competing technology. Our platform can be deployed by 2-3 people with minimal operator training and is suitable for monitoring at fixed locations for longer time periods than is practical for alternative airborne sensors. In Phase II, we will continue to focus on mixing zones in rivers, where vertical mixing of point sources discharges is rapid but may exhibit long downstream distances for full lateral mixing. We will develop technology to better aim and control our sensors. We will identify temperature differentials and associated wastewater types (e.g., process cooling waters, municipal effluents, pulp mill effluents, etc.), outfall configurations (e.g., surface shoreline, submerged single port, multiport diffuser), and ambient conditions that lead to successful monitoring. We will develop tools for hydrodynamic mixing zone model validation and calibrations. We will commercialize our platform by demonstrating deployment with industrial sponsors. We will work with EPA partners on technology verification. Although our platform detects temperature as a water quality parameter, the potential to model the fate and transport of other discharge constituents may be much more widespread, e.g., shoreline recreational exposure to pathogens from wastewater discharges, determination of spatial extent of contaminated sediment deposits from mining operations, detecting the impacts of contaminated groundwater interactions within in groundwater/surface recharge zones, and analysis of thermal refugia habitat for endangered species management.