Subdivision plans involving individual wells and sewage disposal systems must be designed to:

The correct choice emphasizes that subdivision plans involving individual wells and sewage disposal systems must adapt to the existing topography and geological formations. This is crucial because the natural landscape, soil types, and underlying geological features significantly influence the feasibility and safety of well placements and sewage systems.

Properly designing systems that consider these factors helps to ensure the functionality and sustainability of the water supply and sewage disposal. For instance, certain soil types may determine the effectiveness of drainage systems or the suitability of locations for septic tanks. Additionally, understanding the topography can help in preventing contamination and ensuring that the systems operate efficiently.

Designs that do not consider these elements could lead to water quality issues, increased costs, or even public health risks. Therefore, it’s essential to align the design of well and sewage systems with the specific characteristics of the site to ensure compliance and protect both public health and the environment.