Which of the following is a physical effect of erosion and sedimentation?

The physical effect of erosion and sedimentation primarily relates to the changes in the landscape and water quality, and increased water treatment costs is a direct consequence of these processes. When erosion occurs, it can lead to the mobilization of soil and sediments into nearby water bodies. This sediment can carry pollutants, organic matter, and nutrients that can degrade water quality. Consequently, water treatment facilities must work harder to remove these contaminants and sediments, which increases operational costs.

In contrast, increased biodiversity and habitat restoration are typically associated with positive environmental changes rather than consequences of erosion and sedimentation. While recreational opportunities can be affected positively or negatively due to changes in landscape, they are not a straightforward physical impact of the processes under consideration. The focus is on the measurable economic impact, which makes increased water treatment costs the most accurate choice in this context.