From Conservation


What happens when governments ask the public to report water waste?

Ever feel like you're being watched?

Rainfall has been low, the mountain snowpack is thin, and Californians are bracing for another year of scarcity. But this time we've got a raft of data from the historic 2014-2017 emergency to inform drought management in 2021.*

As the drought ravaged California in 2014, the State Water Resources Control Board (SWRCB) issued several orders restricting discretionary outdoor water use like lawn watering and car washing. A revival of these restrictions may be coming this summer, so it’s useful to look at their implementation during the last drought.

If you see something, say something

As with any regulation, enforcement of water use restrictions requires monitoring--after all, you can't enforce a rule if you don't know who is breaking it. Water management agencies sometimes use inspections or patrols to spot violations. Citizen participation can augment agencies’ monitoring capacity, and so often governments invite the general public to join in the effort. Public management researchers call this implementation strategy participatory surveillance.

Participatory surveillance became part of the Golden State’s water conservation regulatory regime during the 2014-2017 drought, as state and local agencies provided telephone hotlines and websites for the public to report water waste anonymously. California communities responded with gusto: over the 32-month emergency, water utilities logged more than 485,000 water waste reports. In a new Water Resources Research paper, Youlang Zhang, David Switzer, and I analyzed water waste reporting across 408 water systems during the 2014-2017 emergency—with important implications for 2021 and beyond.

What kinds of communities get the most water waste reports?

We marshaled a variety of data to explore the factors correlated with water waste reporting, measured as monthly reports per thousand population. Unsurprisingly, the drought severity and the strictness of local water restrictions were among the strongest predictors of complaints: as the drought worsened and restrictions tightened, reports of water waste increased. But our analysis also identified significant social, institutional, and political correlates of reporting.

Education. Water waste reports correlated positively with the share of a community’s population with a college degree—even after adjusting for income, poverty, and racial/ethnic composition. A more educated public, it seems, generates more water waste complaints:

Institutional structure. A clear ordered relationship between utility ownership/organization and water waste reports emerged in the data: all else equal, municipal utilities got the most participation, followed by special districts, with investor-owned utilities getting the lowest participation:

We think that these disparities mainly have to do with familiarity. Municipalities are in most situations far more visible to the public than special district governments and investor-owned systems, and so garner greater media attention and citizen participation.

Party competition. We expected higher voter turnout to correlate with greater water waste reporting, but our analysis didn’t find any significant relationship between the two. However, we found that the composition of the local electorate predicted participatory surveillance in a surprising way: water waste reporting was higher in communities where the electorate was closely divided between Democrats and Republicans.

We measured partisan competition as one minus the local difference between registered Democrats and Republicans, divided by total registered voters.** Are hardcore partisans tattling on their opposition party neighbors? Maybe, but we suspect that heightened party competition simply indicates a more civically engaged public.

Does water waste reporting lead to greater conservation?

We also analyzed the correlation between water waste complaints and conservation outcomes, using the SWRCB’s official measure of conservation (current water use compared with the same month in pre-drought 2013). Yes, waste complaints positively correlated with subsequent water conservation. Substantively, one more complaint per thousand persons predicts a 0.56% increase in monthly water conservation. This effect is small in percentage terms, but represents a great deal of water in a state as big as California: one more complaint per thousand persons per month for each utility would have resulted in 32 billion gallons more water saved during the emergency—enough supply San Francisco for 16 months.

So is participatory surveillance a good idea for water utilities?

With the data on hand we can’t say for sure that participatory surveillance caused the conservation we see. But the results are consistent with the idea that public engagement expands monitoring capacity and suggests that participatory surveillance can enhance the effectiveness of urban water restrictions. More generally, inviting the public to report maintenance or water quality problems could be a useful way to put more “eyes on the street” and help water utilities perform better.

But it’s also clear that participatory surveillance is a social phenomenon, so water waste reporting is likely to work better in some places than others. Authorities looking to manage drought in California and elsewhere should bear in mind that demographic, institutional, and political contexts can condition the effects of public reporting strategies.

Irrigation Karen coming your way

In deputizing the masses, participatory surveillance also changes relationships between citizens, and so could deepen social divisions when people report each other for breaking the rules. Whether the promise of participatory surveillance as a way to strengthen water restrictions justifies its possibly divisive social side-effects is a harder, more fundamental question.

*In past posts I’ve analyzed decoupling, wholesale supply contracts, and enforcement of irrigation restrictions from the last California drought.

**If a utility service area was entirely dominated by one party (i.e., 100% of registrations), then the value of the party competition index would be zero. If the area was evenly divided between Democrats and Republicans (50% Dem, 50% GOP), the value of this party competition index would be one.

New Normals?

​Lessons from California ​water conservation​, 2019

​Reservoirs aren't supposed to look like this.

Tough water times may be back in California. After the Golden State suffered through a historically severe drought from 2012-2017, ​pleasantly wet weather in 2018-2019 refilled reservoirs and replenished mountain snowpacks. But the state’s drought monitor shows that the past few months have trended drier, and water managers are worried that the state might be slipping back toward another drought.

One fortunate legacy of California’s recent struggles with drought is the California Water Board’s investment in data collection and dissemination. Researchers are learning important lessons about water management from that wealth of data on water consumption and conservation. Complete data for 2019 are now available, and I’ve just had a first look.

Three things emerge from my initial cut at the 2019 data that merit mention against the ominous backdrop of a looming drought.

1. ​A way of life

California’s overall urban water use remains down significantly from the pre-drought days. The state government​ ​established emergency conservation ​rules during the peak of the drought, cutting statewide urban water consumption by nearly 25%. But Governor Jerry Brown and other leaders also vowed to make water conservation “a way of life” that would extend beyond the emergency.

Californians seem to have taken the goal to heart, at least in aggregate. Though water conservation is not at the zealous peak we saw in 2015-2016, it remains strong:

Data: California Water Resources Control Board

Falling conservation in 2018 led to some hand-wringing, but conservation rebounded in 2019 to a statewide aggregate 18.1% relative to the state’s official 2013 baseline. That’s pretty remarkable and suggests that much of the reduction in California’s urban water demand is more or less permanent. Absent severe drought or monsoon-like precipitation, California’s overall water conservation will likely remain in the mid-to-high teens for the foreseeable future. That’s a public policy success story.

2. Persistent public-private disparity

One of the most fascinating findings that emerged from my earlier analysis of the California drought with Youlang Zhang and David Switzer was that the state’s private, investor-owned utilities conserved significantly more water than local government utilities during the drought.* We linked that difference in drought response to the institutions that govern water finance. We also found that the public-private conservation gap persisted even after the drought ended, with the greatest disparities during the summer when water demands are at their highest. Back in 2018 your humble blogger forecasted that that “public and private conservation will converge in the spring and diverge again in the summer and autumn.” And indeed, the pattern held: there was essentially no difference between public and private water utility conservation during the winter months, but during the 2018 May-September peak season, California’s investor-owned systems saved more water than their local government counterparts.

Did the pattern persist in 2019? In short, yes:

Data: California Water Resources Control Board

As you can see, public and private utility conservation move in pretty close parallel. During the non-peak period (January-April and October-December), there is essentially no difference in average conservation by ownership. But a public-private gap emerged again during the May-September peak period. In 2018 the difference was 2.3%; in 2019 the gap was smaller—investor-owned utilities saved an average of 1.5% more water than local governments. To give that percentage some context, think of it this way: if public utilities saved at the same rate as private utilities in 2019, the difference would have been about 15 billion gallons, roughly equivalent to the City of Long Beach’s annual water consumption.

The public-private disparity in summertime conservation now also appears to be a way of life in California. The difference is almost certainly related to pricing and revenue. Decoupling über alles.

3. Indoor outpacing outdoor?

​Finally, the five years of data now in front of us show how California’s urban water conservation relates to overall seasonal demand. In 2015, when severe outdoor irrigation restrictions were in effect for much of California, 70% of the state’s conservation came from reduced demand in the peak season. Since then, the share of peak season consumption has fallen to about half:

Data: California Water Resources Control Board

In 2019 non-peak conservation crept up to 52% of overall savings. It’s hard to infer exactly what’s driving this pattern from aggregated monthly data, but the picture suggests that the most persistent water savings seen in California over the past five years has come from indoor efficiency. Average water consumption in 2019 was about 98 gallons per person per day (gpcd), but some cities are far lower. For example, water demand in conservative San Francisco shows hardly any seasonal peak at all, and averages just 42 gpcd—a level approaching the theoretical minimum to sustain developed world conditions.

While there are probably still plenty of savings to be had from indoor efficiency, meeting the challenge of another potential drought year—and driving further sustainable conservation—will require tackling peak demands through pricing and regulation. Get ready for another year of water cops and rate revolts.

* Water geeks Interested readers can see the full study in Policy Studies Journal for the details.

​© 2020 Manny Teodoro

Introducing the Amy Poehler Index

Understanding progressive & regressive water pricing

It's irrigation season, everybody!

By Antonio & Manny Teodoro

How do utilities distribute the costs of drinking water systems to their customers in their rate structures?

The answer is surprisingly complicated, and water utility pricing is often weird. There are lots of other wrinkles and variations, but the vast majority of utilities use one of three basic rate structures:

  1. Uniform, where customers pay the same price for every unit of water that they consume;
  2. Inclining block, which charge higher prices as volume increases; and
  3. Declining block, which charge lower prices as volume increases.

It’s easy to see that these different rate structures distribute costs differently, but how much differently isn’t immediately obvious. How do a utility’s rates apply to low-volume customers compared with high-volume customers?


The answer is important because it carries ​significant implications for affordability and conservation. It also speaks to risk tolerance and questions about fairness. Water is an unusual consumer good because its use is very different at different volumes. For residential customers, low volumes are mostly used for basic needs like drinking, cooking, cleaning and sanitation. Higher volumes are usually for more discretionary uses like lawn irrigation and car washing.

Studies of water rate structures typically put them into the three main categories (uniform, inclining, and declining), which is fine, but can mask some important variation within the inclining and declining blocks. Consider four imaginary rate structures:

A and B are both inclining block rates, but A is more progressive than B because prices increase sharply for A as volume increases. Similarly, C and D are both declining block structures, but C is more regressive than D because ​C discounts higher volumes much more than D.

David Switzer developed a way to measure water rate progressivity​ to reflect that variation, and published a paper last year that uses regression slopes to measure relative progressivity. It’s a creative, rigorous, and smart methodology, but it’s pretty sophisticated and not the easiest approach for communicating with the general public.

In search of a valid but more intuitive way to communicate the idea of progressivity, we struck upon the idea of comparing average unit costs of water at relatively conservative and very high benchmark volumes. What would be appropriate comparative volumes? And how could we frame the measurement in an engaging way?

Enter Amy Poehler

​Amy Poehler was a particularly profligate water customer. In the summer of 2015, while drought ravaged the Golden State, the Parks & Recreation ​star’s Beverly Hills home used 85,000 gallons a month. Meanwhile, a family of four that is fairly conservative with water uses something like 6,000 gallons per month for drinking, cooking, and sanitation.* In other words, Poehler’s home consumed in about two days enough water to comfortably supply a family of four for a month.

​Poehler's house. Maybe she's got a dialysis clinic in the basement?

Shaming celebrities for bad environmental behavior is now something of a ritual in America, and it’s not clear whether exposing excess actually helps. But Poehler’s water consumption provides a convenient benchmark for excess.

The Amy Poehler Index

So to measure progressivity we calculate the total monthly water and sewer bill—including both fixed and volumetric charges—for a customer at 6,000 gallons (a conservative family) and at 85,000 gallons (Amy Poehler’s family), then divide that price by each customer’s total volume. These are average unit costs. The ratio of the two unit prices is the Amy Poehler Index (API). A value of 1.0 means that Amy Poehler and the conservative family pay exactly the same unit price for water. Values less than 1.0 indicate regressive rates (Amy Poehler pays less than a conservative family), and values greater than 1.0 indicate progressive rates (Amy Poehler pays more than a conservative family).

Let’s look at how this works for a couple of large U.S. city water systems under their 2019 rates:

In 2019 Tampa’s fixed monthly charge for water was just $1.50, with no fixed charge at all for sewer. Under Tampa’s inclined five-block rate structure, Amy Poehler would pay $617.82 monthly, while our conservative family would pay just $19.29. On a unit cost basis, those prices equal $7.27 and $3.22 per thousand gallons, respectively. The resulting API is a progressive 2.26.

​Meanwhile, in 2019 Philadelphia charged its customers a fixed $5.12 for water and $7.04 for sewer each month. The City of Brotherly Love then applied declining block water rates that would have charged Amy Poehler $455.69 monthly, and the conservative household $41.10—more than twice the Tampa bill for the same volume. The resulting unit costs turn out to be $5.36 for Amy Poehler and $6.85 for our conservative family, for a regressive API of .78.

The National Progressivity Picture

We used data from the Teodoro & Saywitz 2019 affordability update to calculate API for a nationally representative sample of 399 U.S. water and sewer systems. Average combined water and sewer rates were slightly regressive at .88, but ranged widely from .07 in Anchorage, AK to 3.81 in Phoenix, AZ.

API isn’t as precise as Switzer’s progressivity coefficient, but in our national dataset the two metrics correlate pretty well (ρ=.71). More importantly, the API offers an easy way to understand and improve the ways that communities distribute costs through their rate structures. That seems like the sort of thing Leslie Knope would probably dig.

*That’s about 50 gallons per person per day (gpcd) for a four-person household. 50 gpcd is an indoor efficiency standards for California and Texas.

© 2019 Antonio Teodoro & Manny Teodoro