What are potential environmental effects of poorly maintained septic systems?

Poorly maintained septic systems can lead to significant environmental issues, particularly in relation to the contamination of groundwater and waterways. When a septic system is not functioning correctly, the waste it handles can leak into the surrounding soil and eventually reach groundwater supplies. This can introduce harmful pathogens, nutrients, and chemicals into water sources that are otherwise clean.

The contamination can harm aquatic ecosystems, leading to problems such as algal blooms, which can deplete oxygen in the water and lead to fish kills, and can also make water unsafe for human consumption or recreational activities. Moreover, toxins from a failing septic system may adversely affect the health of local wildlife, which depend on these water sources for survival.

The other options highlight positive impacts which do not align with the reality of environmental consequences stemming from neglecting septic system maintenance. Improved water quality and enhanced soil fertility imply beneficial outcomes, while increased wildlife populations can be misleading without considering the health of the ecosystem, which can decline due to pollution from malfunctioning septic systems.