Reclamation Information Sharing Environment (RISE)

Algae are photosynthetic aquatic organisms that can form large mats called blooms during favorable environmental conditions. Certain species of algae can produce toxins, which cause a phenomenon called harmful algal blooms (HABs). Remote sensing technology can be used to detect a variety of environmental phenomena via satellite. Various water quality parameters indicative of potential HABs may be estimated via remote sensing, including cyanobacteria, chlorophyll-a, phycocyanin, and turbidity. Publicly available HAB detection software tools have been developed by various state and federal agencies to assist in HAB monitoring and to inform field sampling. The tools utilize specific algorithms to estimate the presence of HAB indicators by employing spectral bands unique to different types of satellite imagery. There are tradeoffs between each tool, and it is important to consider their capabilities and limitations before selecting one (or multiple) for monitoring a waterbody. User need and skill are two primary drivers for deciding which tool(s) is the best fit for an end-user. This guidance document includes tool information tables, a decision matrix, and examples to help with tool selection, ultimately, aiming to improve HAB monitoring and response across Reclamation and partner agencies.