Low snowpack this winter has made headlines across the state of Oregon, and the Sandy Basin is no exception. As of mid-March, the Mt. Hood snow gauges show that we are at 6% of average annual snowpack based on data recorded since 1981. This means that at sites that would typically have three feet of snow, we are currently seeing bare ground, and above 5,000 feet on Mt. Hood, hydrologists are finding three feet of snow where there would typically be 10 feet. Currently, the entire state of Oregon is below 50% of average snowpack, and Governor Kate Brown has declared a drought in four counties.
The interesting aspect of this lack of snow is that Oregon has received about an average amount of rainfall. This discrepancy means that we have not had enough cold temperatures for precipitation to fall as snow rather than rain. So far, this lack of snowpack will not be effecting drinking water resources, particularly for those receiving water from the Bull Run reservoirs, as they are primarily fed by spring rains and do not rely on snowmelt to provide water. A bigger impact of the low snow will be felt by our native salmon species.
A research article published earlier this year by employees from the National Marine Fisheries Service and Washington Department of Fish and Wildlife discusses how increases in flow variability will make salmon recovery more challenging. Variability can include high peaks and lower low flows, or changes in the seasonality of typical flow. Pacific Northwest Rivers such as the Sandy typically receive high flows during large winter storms, and again in late spring or early summer as snow melts from our high peaks and feeds the river systems.
Our restoration work on the Sandy River and its tributaries can be critical to help mitigate these flow variation impacts to our river systems and salmon populations. In-stream actions such as the input of large wood and creation of floodplain storage or side channel flows can be important in helping store water. Over time, restoration actions mimic and promote natural river functions, including large wood accumulation, and can help moderate the impacts of increasing flow variability predicted with a warming climate.
In our efforts to restore habitat in the Sandy River Basin, we will continue to monitor current conditions and work with partners to conduct restoration projects that benefit the ongoing recovery of our wild salmon populations.
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