As California heads into its fourth consecutive year of drought, and pronouncements about our water supply are increasingly dire, new data released by the state show that water use and water conservation efforts in cities across the state are highly uneven. Since June of 2014, the State Water Resources Control Board has required urban water suppliers to submit monthly reports of water use, in order to help track conservation efforts.
The data helps reveal insight into patterns of water use around the state, and water suppliers success or failure at achieving water use reduction targets. Water use in California varies from month to month; in our Mediterranean climate, water use over time follows a familiar bell-shaped pattern, with highest usage in the summer months and lower use during the cooler, wetter winter months. In January 2015, water use was 8.8% lower than in January 2014. This was disappointing to water regulators, as urban areas had succeeded in reducing December use by 22.2% when comparing 2014 to 2013.
December was the only month where conservation met the voluntary 20% cutbacks that Governor Jerry Brown called for in an emergency drought declaration in early 2014. December was an anomalously wet month around the state, and it seems most of us watered our lawns and gardens less frequently as a result. However, January saw unusually warm and dry conditions return, driving water use back up, and water use reductions a disappointing 8.8%.
Looking back at the past 8 months, the state as a whole has fallen well short of the governor’s 20% conservation target. This is despite the fact that 95% of water suppliers have enacted some form of drought restrictions.
The data helps show how variable urban water use is around the state. Water managers commonly report average water use in units of gallons per capita per day, or gpcd. When we look at per-capita water use around the state, the biggest users are in Southern California, which has the highest temperatures and the lowest rainfall.
Per-capita use also tends to be higher in wealthy communities. Houses with large lawns and pools are a major culprit. But research has also shown that households use more water for each additional bathroom, even when you hold the number of residents equal. In Orange County, the high water use in the wealthy enclave of Cowan stands out on our map. Here, residents used 281 gallons per capita per day in January 2015. In nearby Santa Ana, where 20% of the population was below the poverty line in 2010, water use was a much lower 56 gpcd.
Around the state, in January 2015 there were 7 water suppliers where residents used more than 200 gallons every day.
One might ask whether it’s fair to call on everyone to cut water use by 20%. For water hogs, this should be easy. But what about areas where water use is already low? Some water suppliers have been running aggressive water conservation campaigns for decades. If nearly everyone is already using efficient appliances and fixtures and taking short showers, where will these additional savings come from?
It’s like squeezing water from a stone, right? Maybe not. A handful of areas have made cuts to their already-low water use. Hopefully new technology, better education and progressive policies will help continue this trend. Otherwise our beloved state of CA may become an inhabitable wasteland.