By Omar Albarbari  Every summer, harmful algal blooms (HABs) affect lakes and ponds across Massachusetts, sometimes leading to swimming advisories or closures. These blooms can produce toxins that threaten people, pets, and wildlife. Monitoring is expensive, and many of our local bodies of water are affected by these algal blooms. At the time of this writing, Hardy Pond in Waltham has an active bloom, resulting in warnings against swimming, fishing, and boating. HABs are rapid overgrowths of cyanobacteria or algae that have many negative consequences. They can block sunlight, exhaust dissolved oxygen and nutrients, and release cyanotoxins into the water. [READ MORE]