Phosphorus is a critical nutrient in aquatic ecosystems, but when present in excessive amounts, it becomes a major pollutant. Its overabundance is often linked to harmful algal blooms, oxygen depletion, and declining water quality. At Savin Lake Services, we focus on educational approaches to help lakefront property owners and communities better understand how phosphorus behaves and what can be done to manage it.
Sources of Phosphorus Pollution
Phosphorus enters lakes and ponds through several human-related and natural pathways. Common sources include agricultural runoff, lawn and garden fertilizers, stormwater runoff, wastewater effluent, and natural processes like plant decay and erosion. These inputs contribute to nutrient buildup and lead to a process called eutrophication.
Eutrophication is the natural aging process of a waterbody and occurs when elevated nutrient levels and muck accumulate over time. This can result in water that is murky, foul-smelling, and depleted of oxygen, especially after algae and aquatic weeds die and decompose. In severe cases, aquatic animals may struggle to survive in these low-oxygen conditions, and recreational uses of the waterbody may become limited.
Phosphorus Binding as a Management Tool
To address excessive phosphorus in aquatic environments, one widely used approach is phosphorus binding. This process involves adding materials to the water that chemically bind with free-floating phosphorus, converting it into a stable form that settles into the sediment and becomes less biologically available.
Common phosphorus binding treatments include:
- Alum (Aluminum Sulfate): Alum is a traditional and proven method for reducing phosphorus levels in lakes and ponds. It binds with phosphate to form aluminum phosphate, which is stable and non-reactive under most environmental conditions.
- Lanthanum-Based Compounds: Products using lanthanum-modified clay can capture and immobilize phosphorus even under varying pH and oxygen levels. These compounds are particularly useful in addressing internal phosphorus loading from sediments.
- Natural Filtration Systems: Techniques like shoreline buffers, restored wetlands, and vegetated swales help intercept and filter phosphorus before it enters waterbodies.
Managing Phosphorus Inputs
Controlling phosphorus at its source is essential to long-term nutrient management. Preventative strategies include:
- Fertilizer Application Practices: Avoiding over-application and using phosphorus-free or slow-release fertilizers can significantly reduce nutrient runoff.
- Erosion Control: Maintaining vegetative cover and using best management practices in agriculture and construction prevent phosphorus-laden soil from entering water.
- Stormwater Management: Techniques like rain gardens, filtration basins, native wetland plants and permeable pavement help manage runoff and filter out nutrients before they reach a lake or pond.
- Livestock and Manure Management: Proper handling and storage of manure helps prevent nutrient leaching into nearby waterways.
Addressing Internal Phosphorus Loading:
In some cases, phosphorus stored in bottom sediments may continue to affect water quality long after external sources are reduced. Hydraulic dredging can be used to physically remove this sediment, but it must be carefully planned to avoid releasing even more phosphorus into the water. Dredging is often paired with post-treatment phosphorus binding to stabilize any remaining nutrients.
Understanding phosphorus dynamics and applying a combination of treatment and prevention strategies is key to maintaining healthy, balanced aquatic ecosystems. By reducing phosphorus availability and curbing new inputs, long-term improvements in water clarity and ecological health are achievable.
Contact Savin Lake Services today to schedule a water quality assessment and take the first step toward cleaner, healthier water.
About Savin Lake Services, A Jones Lake Management Partner
Savin Lake Services is a leading provider of lake and pond management services, delivering expert solutions in aquatic plant management, aeration, hydraulic dredging, mechanical harvesting, water quality monitoring, fisheries management, and shoreline stabilization. As a Jones Lake Management Partner, our team is dedicated to protecting and enhancing waterbodies for HOAs, municipalities, golf courses, and private lake owners. With a focus on sustainability and science-based strategies, Savin Lake Services ensures that lakes and ponds remain healthy, functional, and aesthetically pleasing year-round.
