Archive for April, 2011

Water Use Data

Friday, April 29th, 2011

While in Baltimore, I had a chance to catch up with Susan Hutson and talk about the USGS Water-Use Program. In any water-supply study, you’d think the most elemental question would be, “How much water is being used?” Few of us realize how difficult it can be to come by this data.

Problem is, one rarely can go out and measure water use; data typically have to be provided by others or estimated by various methods. Public water utilities can provide information on domestic and commercial use — if metered — but their customer categories follow no consistent definition. Private domestic wells rarely are metered, so use must be based upon housing or population characteristics. Irrigation use is even harder to estimate, especially if supplied from groundwater. I don’t think we appreciate the skill required to make reasonably accurate estimates of water consumption that can be compared consistently from year to year.

The United States Geological Survey has a nation-wide program for estimating water use. It’s run on a shoestring, but specialists for each State compile an estimate of water use for each county every 5 years. They’ve been doing this since 1950. Techniques have changed — GIS being the most prominent advance — but every effort is made to keep the numbers comparable, so trends can be evaluated.

It hard to say what the rest of the world does. I am unaware of any other nation that runs a comparable nation-wide program. Individual utilities may know much about their customers, but not much about self-provided water. Also, it is not too unusual for a utility to report as much of half its water “missing,” so how good can estimates be in these circumstances? One must wonder if we are basing plans upon on a house of cards. The skillset developed by USGS for estimating water use needs to become more widely available to the world.

Hydropower relicensing

Thursday, April 28th, 2011

August 2011 article (Early View): “Hydropower Relicensing and Climate Change,” by Joshua H. Viers.

(I originally marked this article for the June 2011 issue. However, space requirements for a scheduled featured collection pushed print publication back until the August issue. I regret any inconvenience. The online article remains in Early View.)

This article puts forth the argument that rejecting studies of climate change considering relicensing of hydroelectric facilities in northern California is poorly reasoned and risky. “Given the rapidity of climate warming, and its anticipated impacts to natural and human communities, future long-term fixed licenses of hydropower operation will be ill prepared to adapt if science-based approaches to incorporating reasonable and foreseeable hydrologic changes into study plans are not included.” The author recommends, “At minimum, if the Federal Energy Regulatory Commission is to establish conditions of operation for 30-50 years, licensees should be required to anticipate changing climatic and hydrologic conditions for a similar period of time.”

[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]

Landscape water conservation

Tuesday, April 26th, 2011

June 2011 article (Early View):Value Landscape Engineering: Identifying Costs, Water Use, Labor, and Impacts to Support Landscape Choice,” by David E. Rosenberg, Kelly Kopp, Heidi A. Kratsch, Larry Rupp, Paul Johnson, and Roger Kjelgren.

Efforts to change landscape water consumption have been limited for several possible reasons. First, property owners often overwater, regardless of landscape composition. Changing irrigation behaviors to meet rather than exceed plant water needs can yield significant water savings. Second, utilities assume that property owners have already decided what kind of landscaping they want and owners want to keep what they currently have. Third, urban landscapes are complex systems. Plant composition, site-specific conditions, and maintenance activities interact in many ways so that it is difficult to determine the effect on water use of changing one or more landscape system components. And fourth, little information is available to property website imageowners about the impacts of changing one or more landscape components on their overall water and energy consumption. Costs, required labor, fertilizer, fuel, pesticide and energy use, carbon dioxide (CO2) and particulate emissions, esthetics, and other attributes may also influence property-owner landscape choices. Further, existing information is dispersed among scientific and university Cooperative Extension sources, vendors, and landscape professionals, and is not organized or synthesized to support decision making by property owners.

To address some of these limitations and support property owner landscape decisions, the authors have developed a spreadsheet model that identifies the costs, required labor, water, fertilizers, pesticides, energy, fuel, carbon emissions, and particulates required for, or generated over, the life of a user-specified landscape. Landscapers, landscape architects, contractors, and owners of residential and commercial properties can use the model to identify costs, required inputs, and impacts for a current landscape, landscape plan, or modifications to them.

This is a pretty neat tool! I tried it out, though my balcony at JAWRA World Editorial Headquarters allows for only theoretical testing. I wouldn’t say it’s simple enough for everyone, but it’s not bad either. Check it out at http://vle.cuwcd.com/ .

[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]

E. coli decay

Friday, April 22nd, 2011

June 2011 article (Early View):Population Dynamics of Escherichia coli in Surface Water,” by Vanni Bucci, Marin Vuli?, Xiaodan Ruan, and Ferdi L. Hellweger.

Modelers have traditionally applied a first-order decay to E.coli downstream of, say, a wastewater discharge. Not so, according to this paper! Observed decay kinetics are typically biphasic and there is increasing evidence for growth in the ambient environment. In other words, the living organisms do not behave like dead organic carbon or nitrogen species.

The authors investigated the possible role of growth of an adapted subpopulation in surface water using laboratory experiments with various strains of Escherichia coli in different types of water. Addition of ampicillin (which only kills dividing cells) to these cultures caused a decrease in the total cell density, demonstrating the presence of a growing subpopulation. The results show that E. coli populations in surface water are dynamic and consist of dying native cells and growing surface water adapted cells.

[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]

AWRA Baltimore

Thursday, April 21st, 2011

I’m just back from the AWRA 2011 Spring Specialty Conference, “Managing Climate Change Impacts on Water Resources: Adaptation Issues, Options, and Strategies,” in Baltimore. Associate Editors Ge Sun and Xing Fang joined me in listening to many interesting talks and in scouting out potential JAWRA papers. The Proceedings are online for brief period, then will be available to members only.

The conference was held in the Sheraton, near the Inner Harbor. I donned by Orioles cap and got to see TWO games! Orioles Park at Camden Yards — only three blocks from the hotel — is still, IMHO, the most beautiful of the new old ballparks. My history as an O’s fan goes back to a time when the ballpark (old Memorial Stadium) was shabby and the team (Palmer, Ripken, Murray, etc.) sparkled. :-(

Photos of the conference also are online.

A working water market

Tuesday, April 19th, 2011

June 2011 article (Early View): “The Water Market for the Middle and Lower Portions of the Texas Rio Grande Basin,” by Andrew J. Leidner, M. Edward Rister, Ronald D. Lacewell, and Allen W. Sturdivant.

[This article's abstract does such a nice job, I'm simply going to reproduce it here!]

Regional water management on the United States’ side of the middle and lower portions of the Rio Grande basin of Texas has been aided by a functioning water market since the early 1970s. The water market operates over a region that stretches from the Amistad Reservoir to the Rio Grande’s terminus into the Gulf of Mexico. This article provides an overview of the organizations, institutions, policies, and geographic particulars of the region’s water-management system and its water market. In recent years, this region has experienced high population growth, periodic droughts, and a reallocation of water resources from the area’s agricultural sector to the municipal sector. Demand growth for potable water and a relatively fixed supply of raw water are reflected in increasing prices for domestic, municipal, and industrial water rights. Rising prices in the presence of scarcity and the transfer of water from lower-value to higher-value uses indicate that the market is operating as suggested by economic theory. Reasons for the market’s functionality are presented and discussed. Finally, suggestions are presented which might mitigate potential complications to market operations from aquifer depletion and aid the management of instream river flows.

Rights management

Friday, April 15th, 2011

In the “old days,” an author seeking to reproduce, say, a figure from a JAWRA paper, would write or email us. Usually, they got a “Yeah, sure, go ahead,” and that was the end of things.

Today, we use the RightsLink(R) Copyright Clearance Center. Find the article’s online abstract, and click on the Request Permissions link on the upper right. A menu will pop up to ask you a series of questions. For an academic wanting to reproduce a JAWRA figure in another journal, costs should typically be zero. Agree to the license and there you go!

It’s a few more hoops to jump through, but it keeps everything above board. JAWRA’s policy is to scrupulously respect the letter and spirit of copyright law, and we expect the same of other journals. So, follow the procedures and your own administrators and editors will smile benignly rather than ask embarrassing questions.

Weather forecasting

Thursday, April 14th, 2011

I went downtown today to a Renewable Natural Resources Association (RNRF) Roundtable to hear Dr. Louis Uccellini, Director, National Weather Service, National Centers for Environmental Prediction (NCEP) talk about Trends in Extreme Weather Events. Here in the Washington, D.C. area, 1970′s weather forecasters earned a reputation as congenital liars, as coastal storms typically trace a fine line between dumping tons of snow on us and missing the area entirely, making them notoriously hard to predict. The idea that weather forecasts are little more than educated guesses, though no longer true, continues to plague modern meteorology.

Dr. Uccellini showed how weather forecasting has evolved tremendously since the 1970′s. The NCEP now handles a stream of 3.5 billion observations per day. Forecasts no longer are based on “art,” but upon numerical models run on some of the world’s largest computers. NCEP now can predict almost a week ahead with an accuracy equivalent to 1-day forecasts of three decades ago. In fact, the biggest problem NCEP now faces may be educating local governments and institutions to realize these new forecasts and warnings are the real thing!

So next time you hear it’s going to snow hard, listen to your mother’s advice: put on your galoshes and zip your parka!

Inactive wells hazard

Thursday, April 14th, 2011

June 2011 article (Early View):Modeling the Potential Impact of Seasonal and Inactive Multi-Aquifer Wells on Contaminant Movement to Public Water-Supply Wells, ” by R.L. Johnson, B.R. Clark, M.K. Landon, L.J. Kauffman, and S.M. Eberts.

Ok, here’s something to get you worried, as if you needed anything else: “Wells screened across multiple aquifers can provide pathways for the movement of surprisingly large volumes of groundwater to confined aquifers used for public water supply (PWS). Using a simple numerical model, we examine the impact of several pumping scenarios on leakage from an unconfined aquifer to a confined aquifer and conclude that a single inactive multi-aquifer well can contribute nearly 10% of total PWS well flow over a wide range of pumping rates. This leakage can occur even when the multi-aquifer well is more than a kilometer from the PWS well. … An important implication is that, if an unconfined aquifer is contaminated, multi-aquifer wells can increase the vulnerability of a confined-aquifer PWS well.”

The drawing below summarizes the situation:

Figure from article

Although multi-aquifer wells represent only one type of preferential flow pathway for volatile organic contaminates, the modeling results presented in this article indicate that, where they exist, multi-aquifer wells could be a major factor contributing contaminants to impacted confined-aquifer PWS wells. As a result, multi-aquifer wells, including those that are seasonally active, can lead to situations that may affect public health.

[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]

Thermal impacts

Wednesday, April 13th, 2011

June 2011 article (Early View):Human Impacts to River Temperature and Their Effects on Biological Processes: A Quantitative Synthesis,” by Erich T. Hester and Martin W. Doyle.

Thermal impacts seem to be drawing increased attention. Here, the authors provide a nice summary of thermal effects.

This study summarizes the full spectrum of human thermal impacts to help thermal managers consider the relative magnitudes of all impacts and mitigation options. Also it synthesizes biological sensitivity to river temperature shifts using thermal performance curves, which relate organism-level biological processes to temperature. This approach supplements the popular use of thermal thresholds by directly estimating the impact of temperature shifts on the rates of key biological processes (e.g., growth).

The results quantify a diverse array of human thermal impacts, revealing that human actions tend to increase more than decrease river temperatures. They also provide a practical framework in which to quantify the sensitivity of river organisms to such impacts and related mitigation options.

[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]