Northern California and my home town of Los Altos received more rain than normal in January and February 2017, as the atmospheric river continued to flow here. After five years of drought, California’s surface water and snow pack are above normal.
In early March, bee’s bliss sage (salvia ‘Bee’s Bliss’) begins to bloom, attracting bees. Bee’s bliss sage is a California native plant that is drought tolerant and likes full sun.
Los Altos Weather
In February, Los Altos received over 5″ of rain for the second month in a row. We normally receive about 3″ in these months. We have now received 71% of our normal rain since January 2013, much higher than the 62% last December. But our rainfall during these 4+ years is still 20″ less than normal.
Our overnight temperatures were much warmer than normal, returning to the pattern of the past few years. Most of our February storms were warm, laden with moisture from the tropics. The 14-degree difference between February’s monthly high and low temperatures is the second smallest in over four years. Only December 2014, when we received 8.53″ of rain, has a smaller difference at 13°. Clouds at night keep the nighttime temperature higher by reducing heat loss through radiation.
California surface water and snowpack in great shape
California’s surface water and snowpack are in great shape after the rains of the past two months. Our reservoirs are at or above their historical averages.
California’s snowpack exceeds the normal for this date and for the end of our snow year.
All this is wonderful after five years of drought. A Los Angeles Times article warns “Our wild, wet winter doesn’t change this reality — California will be short of water forever“.
The drought has underlined three important realities that aren’t going to change.
First, the way municipalities use water can be sustainable, even as their population grows, as long as they embrace conservation, water recycling and reuse, and a diverse portfolio of management options. However, agricultural water use at today’s scale in California is not sustainable. Agriculture is literally sucking the state dry. …
Next, we must recognize that the classic definition of water as a sustainable resource — that is, using only the surface and groundwater available on an annual, renewable basis — is no longer tenable for the entire state. …
Finally, it is simply impossible to effectively plan for California’s water future without knowing a lot more about how much water the state has, how much it needs and how these amounts are changing with time.
Groundwater, the third component of stored water, worsened during the drought. As a result, California’s Central Valley continues to sink. A California Institute of Technology report documents that parts of the Central Valley sunk 22″ between May 2015 and September 2016. The Santa Clara Valley, where we live, shows a minor uplift (less than 1″) during the same span.
A large February storm resulted in large releases of water from the Oroville Dam that caused over $100M in damage to the dam. 188,000 residents were evacuated when the top of the dam threatened to give way.
With all this rain, water and sediment are pouring into rivers, the delta, and San Francisco Bay. Sediment is building up in the San Joaquin River that feeds the delta from the south. The river have to be dredged at some time in the future to preserve its capacity to carry water and to protect levees and the surrounding land.
The sediment that reaches the delta and bay is needed to protect Bay Area cities from sea level rise. From this article, “You estimate the Bay and Delta need 13 million cubic yards (10 million cubic meters) of sediment per year to keep up with sea level rise, yet we only get about 400,000 cubic yards (300,000 cubic meters) now”. This San Francisco Chronicle article shows how the north San Francisco Bay turned brown with sediment in February.