Phosphorus is a naturally occurring nutrient found in water, soil, and air. Phosphorus is essential for all living organisms; however, too much phosphorus in Lake Whatcom promotes excessive algae growth. Large algal blooms harm water quality. When algae die, they are decomposed by bacteria in the water. In this decomposition process, bacteria deplete the dissolved oxygen in the water that fish and other aquatic life need to survive. Excessive algae also clogs filters used to treat our drinking water, which increases treatment costs and threatens our community’s water supply. We know residents care about protecting the lake. When homeowners update their property with water quality improvements, they do their part to lower phosphorus levels and improve water quality in Lake Whatcom.