How are government agencies like the local health department working to keep the public safe from the problem of HAB's?

The local health departments work together with local water suppliers and act to monitor harmful algal blooms (HABs)

Explanation:

Harmful algal blooms (HABs) are produced by blooms of algae (phytoplankton), some of them may produce toxins that lead to illness/death in humans and marine organisms (e.g., marine mammals, fish, seabirds, etc). HABs represent a real concern for coastal areas. Cyanobacteria, also known as blue-green algae, may produce HABs both in fresh water and in marine water. Some of the most common causes that may lead to a HAB include the runoff of nutrients (especially those rich in nitrogen and phosphorus), high temperatures, a slow movement of water bodies, etc. The local health departments work to monitor these phenomena by collecting samples in order to analyze the state of the water (i.e., by identifying the presence of toxins, especially cyanotoxins) and give advice to local residents. For these purposes, it is generally required to analyze phytoplankton composition, especially the presence of accessory pigments to chlorophyll a (since these pigments represent good indicators for possible HABs).