What is a potential consequence of untreated stormwater runoff?

Untreated stormwater runoff can significantly harm local ecosystems, which is why this response is the most accurate choice. When stormwater flows over various surfaces, it collects pollutants, debris, chemicals, and sediment. Once this runoff enters local waterways without treatment, it can lead to nutrient pollution, such as excess nitrogen and phosphorus, which may cause algal blooms. These blooms can deplete oxygen in the water, leading to dead zones where aquatic life cannot survive.

Additionally, the introduction of contaminants can disrupt the natural balance of ecosystems, harming plant life and aquatic species. Sedimentation caused by runoff can smother fish eggs and disrupt the habitats of organisms living in the water. Overall, the impacts on local ecosystems include loss of biodiversity, alterations in food web dynamics, and degraded water quality, all stemming from the consequences of untreated stormwater runoff.