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2021 Multijurisdictional Local Hazard Mitigation Plan 9.1.2 Drought Impacts Drought can have a widespread impact on the environment and the economy, although it typically does not result in loss of life or damage to structures, as do other natural disasters. The National Drought Mitigation Center uses three categories to describe likely drought impacts:  Economic Impacts—These impacts of drought cost people (or businesses) money. Farmers’ crops are destroyed; low water supply necessitates spending on irrigation or drilling of new wells; water -related businesses (such as sales of boats and fishing equipment) may experience reduced revenue; power shutoffs may occur.  Environmental Impacts—Plants and animals depend on water. When a drought occurs, their food supply can shrink, and their habitat can be damaged. Drought also has the potential to increase the risk of wildfire.  Social Impacts—Social impacts include public safety, health, power failures, conflicts between people when there is not enough water to go around, and changes in lifestyle. The demand that society places on water systems and supplies—such as expanding populations, irrigation, and environmental needs—contributes to drought impacts. Drought can lead to difficult decisions regarding the allocation of water, as well as stringent water use restrictions, water quality problems, and inadequate water supplies for fire suppression. There are also issues such as growing conflicts between agricultural uses of surface water and in-stream uses, surface water and groundwater interrelationships, and the effects of growing water demand on uses of water. Vulnerability of an activity to drought depends on its water demand and the water supplies available to meet the demand. The impacts of drought vary between sectors of the community in both timing and severity:  Water supply—The water supply sector encompasses urban and rural drinking water systems that are affected when a drought depletes ground water supplies due to reduced recharge from rainfall.  Power supply—Production of all types of energy requires water. Because the energy sector is dependent on water availability, drought can severely impact energy systems.  Agriculture and commerce—The agriculture and commerce sector includes the reduction of crop yield and livestock sizes due to insufficient water supply for crop irrigation and maintenance of ground cover for grazing.  Environment, public health, and safety—The environmental, public health, and safety sector is affected by wildfires, which are detrimental to the forest ecosystem and hazardous to the public. It also experiences the impacts of desiccating streams, such as the reduction of in-stream habitats for native species. Drought generally does not affect groundwater sources as quickly as surface water supplies, but groundwater supplies generally take longer to recover. Reduced precipitation during a drought means that groundwater supplies are not replenished at a normal rate. This can lead to a reduction in groundwater levels and problems such as reduced pumping capacity or wells going dry. Droughts can affect groundwater storage as reserves are drawn down in anticipation of drought impacts. Such conjunctive use assists in drought resilience, but it can take years to replenish the water that was stored. Shallow wells are more susceptible than deep wells. Reduced replenishment of groundwater affects streams. Much of the flow in streams comes from groundwater, especially during the summer when there is less precipitation and after snowmelt ends. Reduced groundwater levels mean that even less water will enter streams when stream flows are lowest. 9-4