That simple fact should already have pinged an alarm bell or two, if you're concerned about global climate change. Several studies have projected that a warmer climate will mean less snow pack in the Sierra over the coming years, and thus less snowmelt. That means less water for an expanding population of Californians, who rely primarily on snowmelt for the water they use to take showers, keep their lawns green, irrigate their farms and feed their livestock.
While Peninsula jurisdictions such as Menlo Park are taking small steps to reduce water use, the issue of water conservation remains mostly theoretical for Bay Area residents, whose water supply is not immediately threatened. Menlo Park's residents consume water at much higher rates than the average Peninsula dweller, but conservation remains a noble goal, rather than an immediate necessity.
"The overall goal is to make the most efficient use of the resource we have available," Lisa Ekers, the city's engineering services manger, said in an interview. Ms. Ekers helps oversee the Menlo Park Municipal Water District, which serves about one-third of the city's residents, in Sharon Heights and areas east of El Camino Real.
The state has mandated a reduction of 20 percent in gross water use by 2020, but the city is more focused on ensuring its water supply starting in 2018, when its current allocation guarantee from the San Francisco Public Utilities Commission, which controls the supply from Hetch Hetchy, expires.
The city needs to be prepared to cut back, Ms. Ekers said, but she doubts the allocation will be drastically reduced.
Accordingly, the city is taking baby steps in its efforts to reduce water use, hoping that a combination of education, law, and "tiered" water rates will nudge residents in the right direction, bringing local water users more in line with those in other Peninsula cities.
Residential customers of the city's municipal water system used 149 gallons per capita per day in fiscal year 2007-08, compared with an average of 90 gallons per day by residential users in the regional system represented by the Bay Area Water Supply & Conservation Agency (BAWSCA). (The agency covers parts of 27 San Mateo County jurisdictions, though it does not include Portola Valley, Atherton or Woodside).
The city is in the process of revising its water-efficient landscaping ordinance, modifying a model developed by BAWSCA. But while City Council members have spent hours debating the ordinance, the outcome of those deliberations isn't likely to make much of a dent in the city's annual water consumption.
BAWSCA estimates that its ordinance would reduce water use in the city's district by 4.75 million gallons annually by 2018, only about one-third of one percent of the total water used (1.3 billion in 2007-08).
Some residents have questioned whether the law can be effectively enforced.
The city is also reviewing its five-year water rate plan, and is considering "different options for rearranging existing tiered rates," with water rates increasing rapidly in relation to water use in order to encourage conservation, Ms. Ekers said.
Thus far, education has been the city's primary tool of choice in persuading residents to conserve water. It has fashioned advertisements aimed primarily at businesses, given away water-saving devices, implemented rebate programs, and sponsored classes on water-efficient landscaping, attended largely by professionals in the field, according to Ms. Ekers. Under a 1993 ordinance, the city also notifies property owners or businesses whose irrigation systems appear to have a leak.
Total water use within the city-run district has ranged from 1.22 billion to 1.45 billion gallons per year over the past decade, sometimes varying widely year to year.
While a trend in total water use is not readily apparent, Ms. Ekers suggested a statistical analysis would reveal consumption heading slightly downward since 2003-04. She attributes that trend to conscious efforts by residents and businesses to conserve, rather than formal action by the city.
The biggest recent change has come in industrial water use, which fell by 25 percent from 2007-08 to 2008-09, likely due to the recession.
While more draconian conservation measures such as water rationing aren't under consideration, the regional water agency has been investigating ways to expand the water supply, Ms. Ekers said. These include examining possible new sources and seeking water recycling opportunities.
Some jurisdictions have even batted around the idea of employing the expensive process of desalination, converting salt water to fresh water — a procedure that might gain traction in coming decades if snowmelt continues to decrease, and if conservation efforts fall short.