Why is Too Much Phosphorus an Issue?

Posted: Tuesday, October 11, 2011


There are situations when there can be too much phosphorus entering our waters. Parts of the Lake Huron shoreline, nearshore areas, and embayments are experiencing the effects of such a situation. Elevated levels of phosphorus contribute to nuisance algae growths. This excessive algal growth leads to eutrophication (when the lake becomes rich in dissolved nutrients and deficient in oxygen).

There are a host of very serious concerns related to too much phosphorus in our waters;

  • Risks to human safety from the threat of harmful algae blooms near drinking water intakes;
  • Unstable fish communities due to harmful algae blooms and low levels of dissolved oxygen;
  • Declines in property values due to loss of recreational opportunities and aesthetics;
  • Disruptions in food web and energy flow that cause negative impacts on species and their habitat;
  • Degraded habitats especially in nearshore, wetlands and tributaries due to increases in algae growth;
  • Beach fouling and loss of tourism revenue; and
  • Added costs to municipalities, industry and the public to protect drinking water sources, and restore recreational areas.

Examples of phosphorus containing materials include; fertilizer, manure, and human waste. There are also naturally occurring sources of phosphorus in lakes, such as decaying organic matter, and eroding rocks and soils.

Dealing with the phosphorus problem means identifying its origin (or source) and then where possible, reducing the amount (or load) of phosphorus coming from those sources and entering Lake Huron. Wastewater (industrial, commercial, municipal, and individual households) and runoff (residential, agricultural, and municipal) are contributors to the phosphorous loading issue.

In terms of individual households, a lack of information appears to be the major barrier preventing residents from making necessary improvements. When people come to understand that their actions and behaviors at home contribute to our environmental issues, they are frequently willing to make the necessary changes.

Opportunities for informing the public on this issue are proactively sought out. Newsletters such as this one are great avenues for providing information needed by local residents. Contact your local conservation authority to see what you can do to combat the phosphorus issue in your home, at work and at play! We’re all part of the problem, which means we can all be part of the solution too!

Be a Part of the Solution

Everyone can practice phosphorus reduction activities. Here are some ideas:

  • Compost your food waste instead of using a kitchen food waste disposal garburator. Keeping food out of wastewater treatment plants helps to reduce nutrient loadings into the lakes.
  • Use phosphorus-free and slow release organic fertilizers on your lawn and garden, and use them only when it’s not raining or when rain is not being forecasted.
  • Have your septic system inspected regularly and ensure it is properly used and maintained.