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2024 Hennepin County All -Jurisdiction Hazard Mitigation Plan <br />Volume 2 — Hazard Inventory <br />4.3.8.3. Spectrum of Consequences B2b <br />Drought impacts are wide -reaching and may come in different forms, such as economic, environmental, <br />and/or societal. A reduction of electric power generation and water quality deterioration are also <br />potential effects. Drought conditions can also cause soil to compact, decreasing its ability to absorb water, <br />making an area more susceptible to flash flooding and erosion. A drought may also increase the speed at <br />which dead and fallen trees dry out and become more potent fuel sources for wildfires. An ongoing <br />drought which severely inhibits natural plant growth cycles may impact critical wildlife habitats. Drought <br />impacts increase with the length of a drought, as carry-over supplies in reservoirs are depleted and water <br />levels in groundwater basins decline. Impacts from drought can also be exacerbated because of dust <br />settling on snow, which causes increased solar energy absorption. As a result, snowmelt takes place earlier <br />in the season and runoff magnitudes increase. <br />The impacts related to early runoff pose problems for many important sectors in Minnesota including <br />agriculture, recreation, tourism, and municipal water supplies. Reservoirs may also be at capacity during <br />these constrained runoff periods, causing spills to be necessary. Ideally, to avoid releases of water <br />downstream, water is captured over a longer timeframe with gradual melting of snowpack. Alternatively, <br />dust produced from the hardening and drying of bare soil can also be exposed as vegetative cover <br />decreases due to extended periods of drought. <br />Although droughts can be characterized as emergencies, they differ from other emergency events in that <br />most natural disasters, such as floods or forest fires, occur relatively rapidly and afford little time for <br />preparing for disaster response. Droughts typically occur slowly, over a multi -year period, and it is not <br />obvious or easy to quantify when a drought begins. <br />4.3.8.4. Potential for Cascading Effects <br />As mentioned, there are many different consequences that can occur from drought. Since droughts <br />typically occur over longer time periods of months, seasons, and years it's possible to start with a few <br />consequences initially, but as the drought persists or worsens, your consequences can start to multiply. <br />This can happen within just the drought hazard itself, but another aspect is adding another hazard on top <br />of or as result of the drought. For example, in drought conditions that have persisted for many months, if <br />you have a rain event occur over a short period of time, the ground will not be able to absorb the moisture <br />quick enough creating a flash flood event. Another common cascading event is the threat and increase of <br />wildfires due to the dry conditions. <br />4.3.8.5. Geographic Scope of Hazard Blc <br />Due to natural variations in climate and precipitation, it is rare for all of Minnesota to be deficient in <br />moisture at the same level at the same time. However, single season droughts, and different magnitudes <br />and intensity over some portions of the State are quite common. In addition, it is typical for all of Hennepin <br />County to be within a drought at the same time, although possible to have part of Hennepin County in a <br />higher level of drought category than another part of the county. <br />4.3.8.6. Chronologic Patterns <br />Drought can occur any time of year, however people mostly think of its effects in the spring and summer <br />months. The onset of summer drought intensity can, and typically, begins with the prior fall and winter <br />144 <br />