wastewater reuse

Posted by on

The language here is so delicate, which is in itself an interesting issue:

It is now possible to imagine a future in which highly treated wastewater will be plumbed directly into California homes as a new drinking water supply.

That’s Matt Weiser on California’s next big step in institutionally normalizing “direct potable reuse” – the treatment of wastewater and its reintroduction directly into our drinking water.

This is a live question right now for colleagues here at the University of New Mexico where one of our water faculty, Caroline Scruggs, has been spearheading research into questions of public acceptance of DPR. The water policy questions are complicated – issues of public acceptance, questions of where the wastewater is going now (in the ocean? into a river where the reuse is already happening downstream?).

In California, where treated effluent is often disposed of directly to the ocean, current questions of water scarcity are driving a robust discussion. Matt’s story outlines the next big step – the beginnings of the establishment of a regulatory framework governing DPR.

An important next step.

rainfall variability is for not fighting over

Posted by on

Fascinating new paper by Lewis Davis at Union College (gated) arguing that the need for collaboration in early agricultural societies with highly variable rainfall led to the development of cultural norms of not fighting over water:

The link between rainfall variation and individual responsibility draws on an extensive theoretical and empirical literature on risk sharing among agricultural households in less developed countries…. I develop a model of informal risk sharing in which attitudes toward collective responsibility are endogenous, determined by the efforts of parents to socialize their children. Parents are willing to incur socialization costs because greater levels of collective responsibility permit their children to credibly commit to larger transfers in an informal risk sharing arrangement. The model predicts the equilibrium level of collective responsibility will be greater where nature is more capricious.

Much math follows, leading to the conclusion that high rainfall variability leads to the general development of more cooperation, less fighting. The tip here came from Tyler Cowan, who makes fun of England and has links to several earlier, ungated versions of the paper. (link fixed, thanks TB for the corrective)

 

When do we stop calling what’s happening on the Colorado River “shortage”?

Posted by on

Putting together a lecture for University of New Mexico Water Resources Program students tomorrow, I’ve been thinking about this quote from MWD’s Bill Hasencamp, in last week’s LA Times:

“Basically, what the models say is that, in the future, most years will be shortage years,” said Bill Hasencamp, the manager of Colorado River resources for the Metropolitan Water District of Southern California. “Shortages are going to be a way of life.”

“Shortage” here has a very particular technical meaning, but it also carries some interesting baggage in terms of how we as a community think about the water supplied by the river we share.

All-American Canal passing through the sand hills west of Yuma, March 2014 by John Fleck

All-American Canal passing through the sand hills west of Yuma, March 2014 by John Fleck

The technical meaning is a reduction in the allocation of water under the U.S. Supreme Court’s 1963 decision in the case of Arizona v. California. The court interpreted the law governing the distribution of the river’s water to mean that California was entitled to 4.4 million acre feet per year, Arizona 2.8 million acre feet, and Nevada 0.3 million acre feet, for a total of 7.5 million acre feet.

The rules weren’t terribly clear about what happened when there was not enough water to do that, or even what “not enough water to do that” might mean. As long as there was water in Lake Mead, everybody could in theory get their full allotment until Lake Mead was sorta empty, and then suddenly we would be in huge trouble. It seemed reasonable to come up with some rules to start early slowing the decline of Lake Mead rather than waiting until it was empty, so in 2007 everyone packaged up some new rules to offer some clarity, the “interim guidelines” (big pdf). They defined “shortage” in terms of the amount of water in Mead on Jan. 1 of any given year. Below 1,075 feet in elevation is “shortage”, and downstream users have to take less than the full amounts laid out in AZ v. CA.

That’s the way Hasencamp is using the word. There’s less water in the river than AZ v. CA allocated, so most years in the future Mead will hover below 1,075, according to the models, and we’ll be in “shortage” most of the time. I don’t fault Bill for using the word – “shortage” is both technically correct, and Hasencamp is using it in a way that sends an important message.

But “shortage” carries some baggage. My big Random House defines it as “a deficiency in quantity”, which implies that we really need the full amount and in shortage we just have to get by with less. Embedded in the language we’re using is the notion that the right and proper way of things is lots water, and the current not-lots-of-water state is some sort of aberration. The core of the argument in my book is that our adaptive response to having less water is finding very successful ways to use less water. Because that seems to be the way it’s going to be, as Hasencamp so clearly explains. Less water is the norm, not an aberration.

We need some more neutral language to describe this future.

Suggestions welcome.

Some optimistic words on the Colorado Basin from Doug Kenney

Posted by on

The University of Colorado’s Doug Kenney is sounding genuinely optimistic in this recent take on the Colorado River’s problems over at Carpe Diem West:

Throughout the basin, a lot of really good innovations are occurring. Conservation has, rightly, emerged as a credible management tool, and not merely something for the hippies to talk about. Cooperation among the states, between the US and Mexico, and between the water users and environmentalists, is arguably at an all-time high.

And yet:

The challenges are all growing, and despite our current momentum, Lake Mead—the unofficial canary in this coal mine—is projected to drop further over the next 2 years. We are doing better—arguably, much better. Nobody should be shy in acknowledging this; some boasting is justified. But we aren’t winning yet.

Kenney is one of the most thoughtful observers of the basin’s issues, from whom I have learned a great deal. The whole thing is worth a read.

Alfalfa in the desert? Really?

Posted by on

One of the journalist’s techniques is to try to start where you think your reader already is, with some piece of knowledge they’re already got, and then lead them to a new place. For me, that often means retracing my own path. I started years ago thinking it was crazy to grow alfalfa in the desert. Squandering water on a cow? Really?

Island Press has posted Chapter 2 of my book as a teaser – watch how I try to shift the frame, to argue that alfalfa actually makes sense. Of course the entire book is worth reading and you shouldn’t stop with one chapter and should buy copies for all your family and friends.

Collaboration on New Mexico’s Rio Grande

Posted by on

A new environmental water sharing governance experiment is underway this late summer on the Rio Grande in central New Mexico in an effort to keep stretches of the river wet for ecosystem benefits. Ollie Reed sketched out the details in this morning’s Albuquerque Journal:

Sandia, Isleta, Santa Ana and Cochiti pueblos each donated 100 acre-feet of San Juan-Chama water to Audubon and the Club at Las Campanas, located in Santa Fe, kicked in an additional 399 acre-feet. The total of 799 acre-feet is being used to supplement the Rio Grande’s flow for the benefit of fish and wildlife.

“In collaboration with the Middle Rio Grande Conservancy District, we will increase the flow in the river for a 35-mile stretch for nearly 24 days,” Julie Weinstein, executive director of Audubon New Mexico, said in a statement issued Wednesday. “Our rivers are especially critical for bird habitat and biodiversity.”

This is a collaborative deal to put water in the river channel for the endangered Rio Grande silvery minnow – among a leading environmental NGO, the federal government, the valley’s largest ag water district and Native American communities. That’s a step away from the litigation and conflict that have been a major feature of the issue’s environmental politics.

The details of the plumbing being used are an interesting part of this project. The MRGCD is using its drain system to target the water at the river stretches where the partners have determined they can get the most benefit for the small amount of water available.

Lower Colorado Basin water savings not as big as I thought

Posted by on

So I need to correct something that I wrote a month ago.

Tony Davis took a deep dive into the Bureau of Reclamation’s data and concluded in a story published this morning (I think accurately) that water conservation savings in the Lower Colorado River Basin will not be as large as I and others have been reporting:

It sounded too good to be true — an official forecast that 2016 water use in Arizona, California and Nevada will be the lowest since 1992.

That forecast from the U.S. Bureau of Reclamation was too good to be true — by the bureau’s own admission. It was widely reported recently as a sign of major progress toward conservation. But what the bureau calls its more accurate forecast, while still showing progress, is significantly higher, predicting water use in the states will be its lowest in 11 years — not 24.

The difference lies in the fact that there are two different water use accounting systems one can look at – the formal “forecast”, which is based on official water orders at the time the forecast is made (pdf here) and the operational plans included in the Bureau’s “24-month study“, which comes out monthly and projects water accounting balances in the reservoirs and among major users out for the next 24 months.

MWD forecast of Colorado River water use

MWD forecast of Colorado River water use

In the 24-month study, you can see that the big difference between the two is the Metropolitan Water District of Southern California. In the “forecast”, Met’s listed as taking 766,000 acre feet this year, but in the 24-month it looks like for planning purposes the Bureau expects Met to take more like a million acre feet. You can see the evolution of Met’s expected water use in this graph from the forecast report. This is the forecast for annual water use as it changes over the course of the year.

CAP forecast water use

CAP forecast water use

On the flip side of this, Arizona’s use of water from the Central Arizona Project has consistently been below the projections used in the original forecast, the result of aggressive conservation efforts in that state. (The y-axis scaling in these graphs makes comparison not exactly easy, looking closely at the numbers.)

So the bottom line: Lower Colorado River water use is currently likely to be the lowest since the second Bush administration, not the first one. Still progress, but not as much as I had hoped.

Thanks to Tony Davis for looking more deeply into this.

Absent deep water use cuts, repeat of the drought of 2000-05 would drain Lake Powell

Posted by on

I’m generally an optimist about our ability to solve our water problems of the western United States, but the drought of 2000-05 provides a boundary condition to my thinking.

Lake Powell, photo by Carol Highsmith, via Library of Congress

Lake Powell, photo by Carol Highsmith, via Library of Congress

In my post-journalism life, one of the most interesting projects I’ve been working on is a study for/by/with Colorado’s West Slope basin roundtables of the risks of climate change and drought to Lake Powell, the largest reservoir in the Upper Colorado River Basin. John Carron at Hydros has been doing the heavy lifting, using the big Colorado River Simulation System model to simulate some sophisticated drought and climate change scenarios, looking at reservoir operation and conservation options needed to keep Lake Powell above elevation 3,525 feet above sea level. 3,525 is the critical point below which we start to lose the ability to generate power and, more importantly, risk busting the Upper Basin’s compact delivery obligations to the Lower Basin.

As a simple proof-of-principle test to help get a handle on the issues and communicate the risks, John also did a relatively simple what-if calculation: what if drought of 2000-05 repeated today? It’s a useful scenario because most of us working on the river today were around back then. We can remember it. Tony Davis did an excellent story this morning on the results:

[A] new study warns that the lake could virtually dry up in as few as six years if the region gets a repeat of the dry spell it experienced from 2000 to 2005.

That could cripple the ability of the Colorado River’s four Upper Basin states to deliver river water to the Lower Basin states of Arizona, California and Nevada, as they’re legally obligated to do.

And it would increase the likelihood of cutbacks in river water deliveries to Arizona, in particular.

Eric Kuhn, who’s leading the study, explained the problem. We started that last big drought with a nearly full Lake Powell:

“Today it’s about half full,” Kuhn said. “You can’t go into a drought like that today if it’s half full. Things will have to change in how we do business.”

The point of the study is to help develop contingency plans ahead of time, so we have the tools in place to manage Powell’s decline before it turns into a mud puddle.

A note on the art: The picture is from the Library of Congress’s collection of the work of photographer Carol Highsmith. Highsmith donated a bunch of her work to the the LoC, freely licensed, and it’s an awesome collection. Yay the commons.

New Pacific Institute report on water demand forecasting

Posted by on

One of the centerpieces of the argument I make in my book, Water is for Fighting Over: and Other Myths about Water in the West, is that changing patterns in water demand (specifically, that we’re using a lot less of it than we used to, across all sectors of the economy) create significant new flexibility in managing water in the West. I drilled down into that argument in a piece published this summer by the Breakthrough Institute:

Unfortunately, a deeply entrenched water management paradigm continues to stand in the way. Consider the Los Angeles Department of Water and Power, one of the nation’s largest municipal water retailers, serving 4 million people. In a major 2005 planning effort, LADWP managers projected that over the coming decade their water demand would rise by 7 percent. In reality, it dropped by 18 percent. Yet despite steady declines, the 2016 version of the agency’s draft water management plan again projects the trend that has resulted in a long term water use decline dating back to the 1990 will reverse itself, with water use rising again from their current low levels.

This pattern of overestimating future demand and underestimating consumer conservation is widespread, and is the major impediment to capturing the benefits that decoupling offers.

Into this public policy mess come Matthew Heberger and colleagues at the Pacific Institute with a helpful new white paper – A Community Guide for Evaluating Future Urban Water Demand:

For much of the 20th century, water use in American cities grew in proportion to population and the economy. Since the 1980s, however, water use in communities across the United States has remained steady or declined despite continued population and economic growth, due to improved water conservation and efficiency and structural changes in the American economy.

While the water sector has undergone a fundamental transformation, the practice of water demand forecasting has been slow to keep pace. Water suppliers routinely overestimate future water demand based on often overstated estimates of population and economic growth and underestimates of the effects of water conservation and efficiency improvements. These inflated estimates of future water needs can result in unneeded water supply and treatment infrastructure, higher costs to ratepayers, and unnecessary environmental impacts.