California Drought

There is little question that San Diego finds itself in a unique position: its water resources are secure for the foreseeable future; we were well south of the fires in the northern part of our state 2021; and, so far, we live free of major restrictions on water use. Nonetheless, it is crucial that we continue to exercise prudence in the face of larger forces. From a broader perspective, we no longer live in ordinary times. According to the United Nations Intergovernmental Panel on Climate Change,

Observed increases in well-mixed greenhouse gas (GHG) concentrations since around 1750 are unequivocally caused by human activities. . . . Each of the last four decades has been successively warmer than any decade that preceded it since1850.

Here are some of the effects of climate change on water.

Among the consequences of climate change is the increased frequency, magnitude, and duration of drought in California. As temperatures rise, it takes more rain (or snow) to produce the same amount of runoff (The New Yorker, 16 August, p. 40).
According to the California Department of Water Resources, "[d]roughts cause public health and safety impacts, as well as economic and environmental impacts. Public health and safety impacts are primarily associated with catastrophic wildfire risks and drinking water shortage risks for small water systems in rural areas and private residential wells.

Photo above from an update on Lake Oroville
from the California Department of Water Resources, 23 July 2021.

In April 2021, Gov. Newsome declared a drought emergency in the Russian River watershed.
In some California towns what used to be a given has changed with the drought conditions. For example, restaurants in Mendocino have closed their restrooms to customers.
Drought is shrinking one of the country's largest resevoirs, Lake Powell, which is at 31.39% capacity.
As of August 2021, Lake Mead, the resevoir behind Hoover Dam, is as at 34% capacity, the lowest since the completion of the dam in 1936.
Arizona's supply of the Colorado River's water will be cut by 20% as a result of the drought.

According to the NASA Earth Observatory, about 53 million people live in drought-affected areas.
According to the U.S. Drought Monitor at the University of Nebraska, 33% of California is at the highest level of drought, D4, Exceptional Drought.
And, in this past July, Gov. Gavin Newsome urged residents to voluntarily reduce their water usage by 15%.
Although San Diego's water supply seems to be safe until 2045, the city still holds that it is illegal to wash off the sidewalk or your driveway with a regular hose or overfill your swimming pool and restaurants aren’t supposed automatically give your table water to drink unless it’s requested. See "Water Use Restrictions" on sandiego.gov
In anticipation of its $1.7 billion budget for the next two years, the San Diego Water Authority has announced "[w]hat the agency calls the “all-in” water rate – which is what it charges customers like the city of San Diego – will rise by 3.6% for treated water and 3.3% for untreated water beginning in January," according to the Times of San Diego.

Based on just these examples, and on available data from local, state, federal, and academic sources, available to anyone, the need to join with our fellow citizens in their ongoing and concerted efforts to conserve water in California cannot be clearer.

According to a study reported in the journal Science, "[g]lobal warming has pushed what would have been a moderate drought in southwestern North America into megadrought territory." Based on a long-term study of hydrological data, researchers have found that the period from 2000 to 2018 was the driest 19-year span since the late 1500s and the second driest since 800 CE.
Map on the left adapted from "Large contribution from anthropogenic warming to an emerging North American megadrought," Science, 17 April 2020, pp. 314-318.