By Louise Bilham, December 18th 2014
Northern California has just experienced its worst storm in five years, making this the wettest December on record. It was powered by the ‘Pineapple Express’, which streamed moisture from Hawaii to the West Coast resulting in heavy rain, snow and strong winds.
Flash flood warnings were given across the Bay Area. Flooded roads caused multiple accidents and falling trees caused the death of two people as well as blocking roads and knocking down power lines. Power outages stretched from the Oregon Coast down to Big Sur on California’s central coast with over 200’000 homes and businesses left without power. This extreme weather also caused mud and debris slides, especially in areas recently affected by wildfires and winds in the high altitudes reached hurricane force.
The severity of the storm meant that schools and state parks needed to be closed. 48 mph winds caused over 200 flights to be cancelled at San Francisco International Airport; ferries were bound to their docks, San Bruno and Montgomery train stations were closed due to flooding and power outages and BART and Muni suffered major delays. Even the San Francisco cable cars were not in service due to concerns on how effective their breaks would be in such wet conditions.
So what does the storm mean for the drought?
The amount of rain the storm brought may be a welcomed sight in a drought stricken California and as the rain continues it would be easy to believe that the drought is coming to an end. However, although it may have brought some relief, due to the severity of the drought that California is experiencing, it is not out of the woods yet.
Experts say that the storm has only improved the drought deficit by 20% and it will take another five or six storms like this one to be able to consider the drought over. According to the National Oceanic and Atmospheric Administration over the next six months the state of California will need another eighteen to twenty-one inches of rain to make up for the drought deficit. This is more than double the amount of rain that the state has received so far this year.
The Sierra Cascade region holds California’s two largest reservoirs, Shasta and Oroville. The storm has caused an increase in Shasta Reservoir from 23% to 29% capacity and has increased Oroville Reservoir from 26% to 30% capacity. Although this is a step in the right direction they have only refilled to the level that they were at in September and they are both still way below what they should be at this time of year. The snow packs in the mountains provide an even clearer indication of the water situation as the spring melts add to the water supply over time. Unfortunately the storm was not cold enough to have a big impact on the snow pack and it only snowed in the higher elevations. The Sierra Snowpack is currently only at 40% of what it should be at this time of year.
“Most of the precipitation was rain. It wasn’t really adding to the snowpack, which is really what they need. Certainly this is good, but it’s going to be just a minor dent in the drought” - Jon Gottschalck, Climate Prediction Center (part of the National Oceanic and Atmospheric Administration).
Along with the excitement of the rain comes the concern amongst experts that Californians will no longer take their water conservation seriously when it is just as important as ever.
"Thursday it will rain, and people will say, 'Oh, I'm very excited,' and Saturday it will rain, and 'Oh, drought’s over. Not even close. This has been three consecutive years of extreme dryness, and that extreme dryness translates to much lower groundwater levels and very dry soils. It’s going to take a lot of rain to break this drought" - Jeffrey Mount, Public Policy Institute of California.