California's ongoing drought "has created a water crisis second to none," says Los Angeles Mayor Eric Garcetti, who is asking residents and businesses to cut their water use by 20 percent over the next two and a half years. Garcetti's description of the situation as a crisis is well placed: Even though L.A. has already reduced its water use by 17 percent over the last seven years and now uses less water than it did 40 years ago, when it had a million fewer residents, the city still imports more than 80 percent of its water, and those sources are drying up.

Garcetti's goal is to cut those expensive water imports in half by 2024. For the moment, he's counting on largely voluntary restrictions for residents, but whether voluntary measures can get the city to Garcetti's goal is an open question. A recent UCLA study of water use in Los Angeles over a 10-year period found that current prices and household allocations were not sufficiently targeting high water users. And the researchers found that previous mandatory restrictions, coupled with increased prices, had a greater impact than voluntary measures.

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The prospect of mandatory restrictions raises issues of fairness and equity, along with concerns about long-term customer support for water conservation. And it makes it all the more important to look at water use from a systems-thinking approach.

Along those lines, the authors of the UCLA study provided recommendations to assist the L.A. Department of Water and Power in designing future water saving measures. The utility was encouraged to revise its two-tiered rate structure, in which higher prices are charged above a certain water use level, to induce higher water savings and to implement dual water-metering to measure indoor and outdoor water use separately.

Dual metering gets at a big part of the problem: Over 50 percent of water use is on landscaping, and those with large lots make up the top 10 percent of L.A.'s water users. With dual meters separating water use, a multitiered pricing structure could preserve water for vital household functions while still making it available for outside use at a higher price. Given that there are still tens of thousands of California homes without water meters at all, the time would seem ripe for this kind of action.

Targeting visible water waste is a key part of the measures enacted in August by the California Water Resources Control Board and now in place in many communities across the state. In addition to mandatory cuts, local water agencies were authorized to prohibit and fine landscape watering that causes visible runoff, hosing down driveways or asphalt, and operating non-recirculating fountains.

It's clear that these kinds of mandatory measures work: Statewide, residential and business water use dropped by 11 percent this August compared to the same period in 2013. "Regulations make better results than voluntary exhortations," says Felicia Marcus, chairwoman of the Water Resources Control Board. "People want to know that everybody else is doing it."

But mandatory measures have their own problems of enforcement (supervising millions of users) and equity (how fairly the restrictions are meted out). How do you restrict one person's water use of 2,000 gallons a day versus his neighbor's 500 gallons when the neighbor re-did his landscaping last year to conserve water? Is a flat mandate to reduce water use by, say, 20 percent equitable? Does it encourage long-term customer support for water conservation?

This also relates to innovative residential water recycling technology just appearing on the market (permitted in the most recent upgrade of the state's plumbing code). It certainly seems that customers who recycle water on their property -- functionally akin to generating electricity from rooftop solar panels -- should be rewarded through the rate structure.

The current drought highlights the need for broad scale realignment of water allocations, use and pricing in California as well as in other drought-prone regions across the country. Perhaps the thorniest part of this process will be earning the support and trust of the public.

On this point, there's no substitute for getting customers to understand what they're paying for. "They're investing in a system, not buying a gallon of water," says Michael Deane, executive director of the National Association of Water Companies.

At the heart of the issue is how best to charge for water when up to 75 percent of the cost is fixed in the delivery system. It isn't going to be easy to raise customer awareness and appreciation for the value of water, the true cost of its delivery and how to responsibly use it in homes and on landscapes. But working this out now will be easier than facing the consequences of running out of water -- way easier.