Archive for September, 2013

ARENA

Monday, September 30th, 2013

Early View article:Development and Integration of a Groundwater Simulation Model to an Open Geographic Information System,” by C.N. Almeida, J. Roehrig, and E. Wendland.

One thing we look for when we publish descriptions of software is the basis behind the model. This is a good example.

Abstract: “This study presents the implementation of a spatial decision support system (SDSS) named ARENA. The program has been developed based on object-oriented concepts using the Java programming language. The SDSS is made up of a groundwater simulation tool coupled to an open geographic information system (open GIS). Both the open GIS and groundwater simulation package share common spatial and nonspatial entities during the modeling process. A dedicated interface provides direct access to the GIS data without the need of external files. The finite element method is used to solve the partial differential equation that governs groundwater flow. The system implementation is presented by depicting the main classes and coupling procedures. A study case demonstrates the applicability of the simulation tool.”

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

Lots of Early View articles

Friday, September 27th, 2013

The October 2013 issue is about to be released. Usually, releasing an issue clears up much of the Early View queue. This time, however, quite a few articles will remain. I’ll explain.

Out Featured Collection on Chesapeake Bay TMDL Development and Application was scheduled for the October 2013 issue, and in fact made it into that issue. However, there was some doubt whether all the loose ends of this large collection could be tied up in time, leaving some possibility it would slip to the December 2013 issue. So, we had to cover our bets by bringing forward enough articles to fill the void. Hence, the large Early View queue.

Keep in mind Early View articles are considered fully published, citeable copies of record. They are exactly what you will see when they are moved to the assigned issue. In the rare case an author spots a problem, we would address this with an erratum, not by changing the article. If you need to cite an Early View article now, including the article’s DOI should avoid any ambiguity.

Precipitation in Saudi Arabia

Friday, September 27th, 2013

Early View article:Precipitation Amount and Intensity Trends Across Southwest Saudi Arabia,” by Chad Furl, H.O. Sharif, Muhammad Alzahrani, Almoutaz El Hassan, and Newfel Mazari.

Understanding precipitation trends in this arid/semiarid region is important for the planning and management of scarce water resources. Long-term trends in precipitation were examined in four unique geographic regions in the coastal and mountainous region of southwest Saudi Arabia. The trends assessment is the first of its size in the study area, and one of few in the region due to the lack of available long-term data needed to properly examine precipitation changes. Both yearly and seasonal trends were assessed using 29 rain gages covering a period of 1945/1946-2009. Results from the modified Mann-Kendall test provide evidence of possible reductions in annual rainfall along the western portion of the escarpment and the plateau further to the east. This finding provides evidence for the general notion that the area is experiencing reduced rainfall. This trend, in part, appears to be driven by declines in the long-term winter rainfall record.

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

Lumpy investments

Thursday, September 26th, 2013

Early View article:Water Quality Trading with Lumpy Investments, Credit Stacking, and Ancillary Benefits,” by Adam H. Lentz, Amy W. Ando, and Nicholas Brozovic?.

Good abstract: “This paper studies the economics of a water quality trading market in a predominantly agricultural watershed, and explores the effects of credit stacking in such a market when buyers and sellers of pollution credits can only reduce pollution with large, discrete investments that yield discontinuous supply and demand. The research simulates hypothetical water quality trading markets in the corn-belt area of Illinois, where wastewater treatment plants (WWTPs) can pay farmers to reduce nutrients by installing wetlands and farmers may or may not be allowed to earn payments for multiple services from one wetland. We find that wetlands are a more cost-effective way to mitigate nitrogen pollution than abatement by WWTPs. Stacking credits may improve social welfare while providing more ecosystem services if there is enough demand for the primary credit in the market (nitrogen) to cover most of the cost of installing the wetland but the supply of nitrogen credits is not exhausted. However, in the presence of lumpy pollution reduction activities, the effects of allowing stacked credit sales are idiosyncratic and not necessarily positive; stacked payments may or may not satisfy additionality. The results imply that credit trading for nitrogen is likely to make society better off, but the effects of allowing farmers to receive multiple payments from a single wetland depend on details of the situation.”

Decade of geomorphic response

Monday, September 23rd, 2013

Early View article:A Decade of Geomorphic and Hydraulic Response to the La Valle Dam Project, Baraboo River, Wisconsin,” by Samantha L. Greene, Austin Jena Krause, and James C. Knox.

The big question in dam removal is, What happens afterwards? Here’s a decade-long study.

The authors investigate stream response to the La Valle Dam removal and channel reconstruction by estimating channel hydraulic parameter values and changes in sedimentation within the reservoir. The designed channel reconstruction after the dam removal included placement of a riffle structure at the former dam site. Stream surveys undertaken in 1984 and in 2001 were supplemented with surveys in 2009 and 2011 to study the effects of the instream structure. We created a model in HEC-RAS IV and surface maps in Surfer© using the 1984, 2009, and 2011 surveys. The HEC-RAS IV model for 2009 channel conditions indicates that the riffle structure decreases upstream channel shear stress and velocity, causing renewed deposition of sediment within the former reservoir. The authors estimate by 2009, 61% of former reservoir sediments were removed during dam removal and channel reconstruction. Between 2009 and 2011 renewed sedimentation within the former reservoir represented approximately 7.85% of the original reservoir volume. The HEC-RAS IV models show the largest impacts of the dam and riffle structure occur at flood magnitudes at or below bankfull. Thus, the riffle and the dam similarly alter channel hydraulics and sediment transport. As such, the models indicate that the La Valle Dam project was a dam replacement rather than a removal. The results confirm that channel reconstruction method can alter channel hydraulics, geomorphology, and sediment mobility.

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

Shutdown madness

Friday, September 20th, 2013

Once again the U.S. Government faces an October 1 budget shutdown. Most of our Government authors, reviewers, and even a couple of Associated Editors, will be told to stay out of the office and not perform any official duties. So much for the world’s remaining superpower!

First of all, let me assure you no manuscripts are going to be automatically rejected for inactivity because of the shutdown. We will show a similar understanding for late government reviewers. Deadlines will be extended accordingly. In some cases, we may need to reassign an Associate Editor or find new reviewers. Schedules will invariably slip, but we will do our best under the circumstances.

We are asking those facing furloughs to do what they can to prepare. Especially if you are a reviewer, please try to complete your review before October 1. Authors may want to get in their submittal or revision before the deadline. Hopefully, sanity will return and any furlough will be short, but you never know.

River characteristics in France

Friday, September 20th, 2013

Early View article:Uncertainty Models for Estimates of Physical Characteristics of River Segments Over Large Areas,” by Nicolas Lamouroux, Hervé Pella, Ton H. Snelder, Eric Sauquet, Jérome Lejot, and Ude Shankar.

JAWRA has carried many articles about river networks and elevation models in the United States. For a change, here’s one about France.

“Using test data with varying degrees of independence, we derived analytical models of the uncertainty associated with estimates of upstream catchment area (CA), segment slope, and mean annual discharge for all river segments of a digital representation of the hydrographic network of France. Although there were strong relationships between our test data and estimates at the scale of France, there were also large relative local uncertainties, which varied with the physical characteristics of the segments and their catchments. Discharge and CA were relatively uncertain where discharge was low and catchments were small. Discharge uncertainty also increased in catchments with large rainfall events and low minimum temperature. The uncertainty of segment slope was strongly related to segment length. Our uncertainty models were consistent across large regions of France, suggesting some degree of generality. Their analytical formulation should facilitate their use in large-scale ecological studies and simulation models.”

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

Characterizing rainwater harvesting

Thursday, September 19th, 2013

Early View article: Characterizing Rainwater Harvesting Performance and Demonstrating Stormwater Management Benefits in the Humid Southeast USA,” by K.M. DeBusk, W.F. Hunt , and J.D. Wright.

Recent droughts in the humid southeastern United States have led to increased implementation of rainwater harvesting (RWH) systems. The objectives of this study were twofold: (1) present usage characteristics and performance results for four RWH systems installed in humid North Carolina as compared with systems located in arid/semiarid regions and (2) identify system benefits and modifications that could help improve the performance of RWH systems installed in humid regions of the world.

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

Low Impact Development

Wednesday, September 18th, 2013

Early View article: Modeling Hydrologic Benefits of Low Impact Development: A Distributed Hydrologic Model of The Woodlands, Texas,” by George Doubleday, Antonia Sebastian, Tatyana Luttenschlager, and Philip B. Bedient

This article uses a unique distributed hydrologic model, Vflo™, combined with historical (1974) and recent (2008 and 2009) rainfall events to evaluate the long-term effectiveness of The Woodlands natural drainage design as a stormwater management technique. This study analyzed the influence of LID in The Woodlands by comparing the hydrologic response of the watershed under undeveloped, developed, and highly urbanized conditions.

The Woodlands near Houston, Texas is one of the premier master-planned communities in the United States. Unlike in a typical urban development where riparian corridors are often replaced with concrete channels, pervious surfaces, vegetation, and natural drainage pathways were preserved as much as possible during development. The results show that The Woodlands drainage design successfully reflects predeveloped hydrologic conditions and produces peak flows two to three times lower than highly urbanized development. Furthermore, results indicate that the LID practices employed in The Woodlands successfully attenuate the peak flow from a 100-year design event, resulting in flows comparable to undeveloped hydrologic conditions.

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

Hedging rules for Lake Okeechobee

Monday, September 16th, 2013

Early view article:Hedging Rules for the Operation of Lake Okeechobee in Southern Florida,” by Gene J.-Y. You.

This study deals with operational problems related to the management of Lake Okeechobee and the challenges involved in the implementation of hedging policy. The authors examine the implications of applying a theoretical hedging rule approach, comprising inter- and intrayear models, for the management of Lake Okeechobee and explore several optional hedging policies. The results demonstrate that hedging rules could reduce profit loss particularly under serious water stress, and might be applied sooner to mitigate the risk of severe water shortages. They suggested that the management of Lake Okeechobee should consider both short- and long-term hedging nested. It is also demonstrated that the practical applicability of rolling decision making with updated forecast. Based on the results of the model, the merits of explicit optional hedging rules are demonstrated.

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