During spring, when the snow melts and there are heavy rains, it is the time of year when the largest amounts of excess phosphorus are washed off the landscape into surrounding ditches, streams, and lakes. Phosphorus is an essential nutrient required by plants and animals. It is found in human and animal waste as well as fertilizers and wastewater effluent. But when it becomes overly abundant in the aquatic environment, it can lead to algal blooms and zones of low oxygen, which threaten wildlife and human health. The excess phosphorus that enters waterbodies this spring—as well as throughout the year—will feed algal blooms later this summer. It is important to reduce the amount of phosphorus that ends up in local waterways and keep it on the landscape where it is needed.
Nutrient enrichment and excess phosphorus are a particular issue in the Lake Erie basin, which suffers from toxic and nuisance algal blooms each year. The St. Clair Region Conservation Authority (SCRCA) has been working with local stakeholders to develop a phosphorus management plan for the Sydenham River watershed, which is located in the Lake Erie basin. The ultimate goal of the project is to improve local water quality and reduce the impact of this nutrient downstream by identifying local sources of phosphorus, determining best-value solutions, and by engaging the larger watershed community. The plan is set to be released this year and has been undertaken with financial support from Environment and Climate Change Canada and the Ontario Ministry of the Environment, Conservation and Parks.
Here are some things you can do to help reduce the amount of phosphorus that ends up in the water:
- Phosphorus can build up in the soil, so if you use fertilizers or other nutrient sources, ensure that you are only using the amount needed by the plants and are not over-applying. Also consider when you are applying these nutrients – do not apply to frozen ground or before a heavy rain as it will be washed away.
- Reduce the amount of pavement and other hard surfaces on your property since they do not allow rainwater to soak into the ground and instead cause more runoff that carries phosphorus and other pollutants to lakes and rivers via storm drains and ditches.
- To reduce and slow down runoff, consider planting a rain garden, using rain barrels, or establishing vegetation along watercourses.
- If you have a septic system, ensure it is receiving regular maintenance and doesn’t become clogged. Septic tanks need to be cleaned out when solids fill a third of the tank. Ensure the leaching bed is functioning properly and do not pave or drive over it. Divert excess water away from the leaching bed and ensure downspouts are not connected to the septic tank.
- Support the conservation and restoration of natural areas like forests and wetlands.
- If you are a farmer or rural landowner in the region, find out about other beneficial practices and grant opportunities available to you by contacting the SCRCA (or your local conservation authority)
You can learn more about the impact of this nutrient and watch a short presentation on phosphorus in the Sydenham watershed by visiting: www.sydenhamriver.on.ca/phosphorus