Why is it a problem?
The Bayswater Brook is the fifth highest contributor of nutrients into the Swan River. High nutrient levels can have serious environmental consequences.
Bayswater Brook is mainly situated on Bassendean sands, which are poor at retaining nutrients. This means any nutrients applied to the surface will seep through the soil and enter the groundwater, which eventually enters water bodies within the catchment and causes problems.
Plants require nutrients, specifically nitrogen and phosphorous to grow. However, in high quantities these nutrients can cause water quality problems, including algal blooms. The increased algae growth decreases the amount of sunlight available to other plant life in the water, which prevents photosynthesis from occurring and can lead to fish deaths.
Algae can grow until it has used up all nutrient supplies, and will then start to die. In the process of decomposition, the algae will consume all the available oxygen in the water, meaning other organisms that need oxygen to survive will either have to leave the ecosystem or die.
Water bodies that have algal blooms have a foul smell due to the rotting organic matter, making them unsuitable for recreational purposes. This occurs periodically in the Swan River and local wetlands.