What does a high groundwater level indicate for contractors during excavation?

A high groundwater level during excavation indicates that the soil is likely saturated with water, which can significantly affect construction activities. When the groundwater level is high, it introduces risks such as water seepage into the excavation site, which can lead to instability in the soil. This condition necessitates additional measures to manage water inflow, such as dewatering systems, which can indeed lead to extra costs.

Moreover, the presence of high groundwater can compromise soil bearing capacity, making it less stable and potentially increasing the risk of soil failure. Therefore, contractors need to plan for these additional expenses in their budget as high groundwater levels often necessitate more complex foundation designs or treatments to ensure safety and structural integrity.

The other options do not reflect the realities of dealing with high groundwater levels: it does not inherently improve soil stability and can actually decrease it (contradicting increased stability), and it raises, rather than reduces, the likelihood of water management issues during excavation.