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2021 Multijurisdictional Local Hazard Mitigation Plan  Environment—The exposure and vulnerability of the environment to dam failure is likely to change as a result of climate change. Ecosystem services may be used to mitigate some factors that could increase the risk of design failures, such as increasing the natural water storage capacity in watersheds above dams. 17.2.2 Drought Climate Change Impacts on the Hazard Future increases in temperature, regardless of whether total precipitation goes up or down, will likely cause longer and deeper California droughts, posing major problems for water supplies, natural ecosystems, and agriculture. Global and local water resources are already experiencing the following stresses without climate change:  Growing populations  Increased competition for available water  Poor water quality  Environmental claims  Uncertain reserved water rights  Groundwater overdraft  Aging urban water infrastructure. With a warmer climate, droughts could become more frequent, more severe, and longer lasting. The 2012-2016 California drought led to the most severe moisture deficits in the last 1,200 years and a 1-in-500 year low in Sierra snowpack. Consecutive years of low or no snowpack are especially worrisome (California 4th Climate Assessment, SF Bay Region, 2019). It is expected that San Mateo County’s precipitation patterns will continue to exhibit high year-to-year variability, with very wet and very dry years. Meaning, there is ample opportunity for multiple, consecutive very dry years. The California 4th Climate Assessment for the SF Bay Region predicts, under a high emissions scenario, average Sierra Nevada snowpack is likely to decline by nearly 20% in the next 2-3 decades, 30% to 60% in mid-century, and by over 80% in late century. By addressing current stresses on water supplies and by building a flexible, robust program, the County will be able to respond more adeptly to changing conditions and to survive dry years. Exposure, Sensitivity and Vulnerability The following summarizes changes in exposure and vulnerability to the drought hazard resulting from climate change:  Population—Population exposure and vulnerability to drought are likely to change as a result of climate change. It is expected that greater numbers of people may need to engage in behavior change, such as water saving efforts, to offset expected increasing drought conditions. Broad public health concerns are important considerations and likely impacts, such as limited access to clean water sources.  Property—Property exposure and vulnerability may increase as a result of increased drought resulting from climate change, although this would most likely occur in non-structural property such as agriculture 17-12