How does the California drought impact water supply?

The correct response highlights that drought conditions in California significantly reduce the availability of surface water. During a drought, there is typically less precipitation leading to lower river flows, decreased reservoir storage, and overall diminished surface water supplies. This scenario forces communities and ecosystems that depend on surface water to face water shortages.

In this context, natural systems such as rivers and lakes experience lower water levels, which can negatively impact not only human water supply but also the biodiversity that relies on these water sources. Additionally, the reduction in available surface water can heighten competition for limited resources among agricultural, urban, and environmental needs.

The other options do not accurately reflect the reality during drought conditions: surface water availability does not increase, reliance on groundwater typically increases rather than decreases, and building new reservoirs may be a response to water scarcity but does not occur during drought periods when resources are limited. Thus, the most accurate understanding of the impact of drought on water supply is the significant reduction of available surface water.