WaterWired

CRS InFocus Report: 'Safe Drinking Water Act (SDWA) - Water System Security and Resilience Provisions'

From Elena H. Humphreys comes this CRS InFocus report (1 March 2021): 'Safe Drinking Water Act (SDWA): Water System Security and Resilience Provisions'.

Download CRS_InFocus_SDWA_WS_Security_Resilience_1March2021

Introduction
The disruption of a safe and reliable water supply remains a long-standing concern related to the protection of public health. Several events have increased congressional attention to water system security and resilience from events that could disrupt the provision of water supply. These include a cyberattack on an automated system at a water treatment plant serving a Florida community and water service disruptions in Texas related to frigid weather and power losses. Intentional acts and natural hazards can damage water infrastructure, including automated systems that control treatment, resulting in the interruption of safe and reliable drinking water.

Water systems are one type of critical infrastructure (CI) covered by broader efforts to improve CI security. The U.S. Environmental Protection Agency (EPA) has been designated the lead agency responsible for water sector security, including cybersecurity (Executive Order 13636). (See CRS Report R45809, Critical Infrastructure: Emerging Trends and Policy Considerations for Congress.)

To address both intentional acts and extreme weather that may threaten water systems, Congress added several provisions to the Safe Drinking Water Act (SDWA) to support the safety of water supplies and resilience of water systems. Primarily found in SDWA Part D “Emergency Powers,” these provisions range from risk and resilience assessment and emergency response planning, to civil and criminal penalties against those who tamper or attempt to tamper with a public water system (42 U.S.C. §300i-300i- 4). The Public Health Security and Bioterrorism Preparedness and Response Act of 2002 (the Bioterrorism Preparedness Act; P.L. 107-188; Title IV) added or revised many of these SDWA provisions.

After first focusing on security, Congress expanded SDWA provisions to address water system resilience to a range of risks such as droughts, floods, wildfires, and other extreme weather/natural events. America’s Water Infrastructure Act of 2018 (AWIA; P.L. 115-270) amended provisions to expand the risks that water systems evaluate and authorized grant programs to increase resilience.

In addition, as a condition of taking on primary enforcement authority, SDWA requires states to have an adequate plan for providing safe drinking water under emergency circumstances, such as “earthquakes, floods, hurricanes, and other natural disasters, as appropriate” (42 U.S.C. §300g-2(a)(5)). The act authorizes various financial assistance programs that may assist water systems in addressing threats that could disrupt water service. These authorized resilience-related financial assistance programs have yet to receive appropriations, or began receiving appropriations in FY2020.

Read on and enjoy!

"There's nothing sadder than an old hipster." - Lenny Bruce (quoted in @nytimes via @TheWeek)

CRS Report: 'U.S. Geological Survey (USGS) Streamgaging Network - Overview and Issues for Congress'

Anna E. Normand is the one behind this CRS report (2 March 2021): 'U.S. Geological Survey (USGS) Streamgaging Network: Overview and Issues for Congress'.

Download CRS_Report_USGS_Streamgaging_Network_2March2021

I don't often comment on CRS reports that I post but this one is an exception. I am not an expert (not even close!) on streamgaging and networks. This report has a lot of information on the state-of-the-art, among other things. So if you are like me, give it a look.

Click on the graphics to display/enlarge them. I went overboard with them.

Overview
Streamgages are fixed structures at streams, rivers, lakes, and reservoirs that measure water level and related streamflow—the amount of water flowing through a water body over time. The U.S. Geological Survey (USGS) in the Department of the Interior operates streamgages in every state, the District of Columbia, and the territories of Puerto Rico and Guam. The USGS Streamgaging Network encompasses 11,340 streamgages, which record water levels or streamflow for at least a portion of the year. Approximately 8,460 of these streamgages measure streamflow year round as part of the National Streamflow Network. The USGS also deploys
temporary rapid deployment gages to measure water levels during storm events, and select streamgages measure water quality.

Streamgages provide foundational information for diverse applications that affect a variety of constituents. The USGS disseminates streamgage data free to the public and responds to over 887 million requests on streamflows annually. Direct users of streamgage data include a variety of agencies at all levels of government, private companies, scientific institutions, and recreationists. Data from streamgages inform real-time decisionmaking and long-term planning on issues such as water management and energy development, infrastructure design, water compacts, water science research, flood mapping and forecasting, water quality, ecosystem management, and recreational safety.

Congress has provided the USGS with authority and appropriations to conduct surveys of streamflow since establishing the first hydrological survey in 1889. Many streamgages are operated cooperatively with nonfederal partners, which approach the USGS and sign joint-funding agreements to share the cost of streamgages and data collection. The USGS Cooperative Matching Funds (CMF) Program provides up to a 50% federal match with tribal, regional, state, and local partners. The average nonfederal cost-share contribution increased from approximately 50% in the early 1990s to approximately 69% in FY2020. In the early 2000s, the USGS designated federal priority streamgage (FPS) locations based on five identified national needs. The SECURE Water Act of 2009 (Title IX, Subtitle F, of P.L. 111-11) directed the USGS to operate no fewer than 4,700 federally funded streamgages by FY2019. In FY2020, 3,470 of the 4,760 FPSs designated by the USGS were operational, with 35% of FPSs funded solely by the USGS FPS program funds and the rest funded by a combination of federal and nonfederal funds.

Congressional appropriations and agreements with 1,400 nonfederal partners funded USGS streamgages at $194.9 million in FY2020. The USGS share included $24.7 million for FPSs and $29.4 million for cooperative streamgages through CMF. A dozen other federal agencies provided $38.0 million. Nonfederal partners, mostly affiliated with CMF, provided $102.8 million. In FY2021, Congress appropriated the same amount of funding as in FY2020 for FPS and CMF streamgages. Congress apropropriated $24.5 million in FY2021 for the Next Generation Water Observing System (NGWOS), an effort to establish dense water monitoring networks in representative watersheds in order to model streamflow in analogous watersheds.

The USGS uses appropriated funding to develop and maintain the USGS Streamgaging Network. The USGS and numerous stakeholders have raised funding considerations including user needs, priorities of partners, federal coverage, infrastructure repair, disaster response, inflation, and technological advances. Some stakeholders advocate for maintaining or expanding the network. Others may argue that Congress should consider reducing the network in order to prioritize other activities and that other entities operate streamgages tailored to localized needs. Congress might also consider whether to invest in streamgage restoration and new technologies.

Congress may consider outlining the future direction for the USGS Streamgaging Network through oversight or legislation. The USGS failed to meet a deadline set by the SECURE Water Act of 2009 to operate no fewer than 4,700 FPSs by FY2019. Congress has provided level funding for FPSs while directing the USGS through appropriations legislation to increase investment in the NGWOS. Congress may consider such policy options as pursuing both the FPS mandate and the NGWOS simultaneously, amending the SECURE Water Act of 2009, and determining the relative emphasis of the NGWOS in the agency’s streamgaging enterprise.

And how about this Delaware River Basin project:

Enjoy!

“Midlife crisis is climbing to the top of the ladder only to discover that it’s been leaning against the wrong wall.” – Joseph Campbell

Water, Volume 13, Issue 4 (February-2 2021): Hydrology, Hydraulics, Hydrodynamics & Hydrogeology; Wastewater Treatment & Reuse; Policy, Governance & Management; and More!

Time for Water! The journal, that is - Water, Volume 13, Issue 4 (February-2 2021).There are 188 articles plus other features - click here to examine the entire issue (only the articles are here),

Enjoy!

Cover Story

Article: Assessing Chlorophyll a Spatiotemporal Patterns Combining In Situ Continuous Fluorometry Measurements and Landsat 8/OLI Data across the Barataria Basin (Louisiana, USA)

Ivan A. Vargas-Lopez, Victor H. Rivera-Monroy, John W. Day, Julie Whitbeck, Kanchan Maiti, Christopher J. Madden and Armando Trasviña-Castro

Water 2021, 13(4), 512; doi:10.3390/w13040512

 

Featured Papers

Article: Hydrogeological and Geochemical Characteristics of the Coastal Aquifer of Stromboli Volcanic Island (Italy)

Paolo Madonia, Gloria Campilongo, Marianna Cangemi, Maria Luisa Carapezza, Salvatore Inguaggiato, Massimo Ranaldi and Fabio Vita

Water 2021, 13(4), 417; doi:10.3390/w13040417

Article: Utilization of Biomass Derived from Cyanobacteria-Based Agro-Industrial Wastewater Treatment and Raisin Residue Extract for Bioethanol Production

Olga N. Tsolcha, Vasiliki Patrinou, Christina N. Economou, Marianna Dourou, George Aggelis and Athanasia G. Tekerlekopoulou

Water 2021, 13(4), 486; doi:10.3390/w13040486

Article: Major Elements in the Upstream of Three Gorges Reservoir: An Investigation of Chemical Weathering and Water Quality during Flood Events

Di Wang, Guilin Han, Mingming Hu, Yuchun Wang, Jinke Liu, Jie Zeng and Xiaoqiang Li

Water 2021, 13(4), 454; doi:10.3390/w13040454

Article: Theoretical and Empirical Characterization of Water as a Factor: Examples and Related Issues with the World Trade Model

Ignacio Cazcarro and Albert E. Steenge

Water 2021, 13(4), 459; doi:10.3390/w13040459

Article: Occurrence and Sources of Synthetic Musk Fragrances in the Sewage Treatment Plants and the Han River, Korea

Ju-Hee Hong, Jun-Yeon Lee, Hyun-Ju Ha, Jin-Hyo Lee, Seok-Ryul Oh, Young-Min Lee, Mok-Young Lee and Kyung-Duk Zoh

Water 2021, 13(4), 392; doi:10.3390/w13040392

Article: Cadmium Accumulation and Kinetics in Solea senegalensis Tissues under Dietary and Water Exposure and the Link to Human Health

Maria D. Pavlaki, Rui G. Morgado, Violeta Ferreira, Rui J. M. Rocha, Amadeu M. V. M. Soares, Ricardo Calado and Susana Loureiro

Water 2021, 13(4), 522; doi:10.3390/w13040522

Article: Influence of Power Take-Off Modelling on the Far-Field Effects of Wave Energy Converter Farms

Gael Verao Fernandez, Vasiliki Stratigaki, Nicolas Quartier and Peter Troch

Water 2021, 13(4), 429; doi:10.3390/w13040429

Article: Multi-Biomarker Responses of Asian Clam Corbicula fluminea (Bivalvia, Corbiculidea) to Cadmium and Microplastics Pollutants

Susana Parra, Simone Varandas, Dércia Santos, Luís Félix, Lisete Fernandes, Edna Cabecinha, Jesús Gago and Sandra Mariza Monteiro

Water 2021, 13(4), 394; doi:10.3390/w13040394

Article: Morphometry-Driven Divergence in Decadal Changes of Sediment Property in Floodplain Water Bodies

Pongpet Pongsivapai, Junjiro N. Negishi, Hokuto Izumi, Paolo A. Garrido and Kanta Kuramochi

Water 2021, 13(4), 469; doi:10.3390/w13040469

Article: Ecotrophic Effects of Fishing across the Mediterranean Sea

Donna Dimarchopoulou, Ioannis Keramidas, Georgios Sylaios and Athanassios C. Tsikliras

Water 2021, 13(4), 482; doi:10.3390/w13040482

Article: Terraced Landforms Onshore and Offshore the Cilento Promontory (South-Eastern Tyrrhenian Margin) and Their Significance as Quaternary Records of Sea Level Changes

Alessandra Savini, Valentina Alice Bracchi, Antonella Cammarosano, Micla Pennetta and Filippo Russo

Water 2021, 13(4), 566; doi:10.3390/w13040566

Article: Effects of Malachite Green on the Microbiomes of Milkfish Culture Ponds

Chu-Wen Yang, Yi-Tang Chang, Chi-Yen Hsieh and Bea-Ven Chang

Water 2021, 13(4), 411; doi:10.3390/w13040411

 

General

Review: Phosphorus Removal from Wastewater: The Potential Use of Biochar and the Key Controlling Factors

Khatereh Nobaharan, Sepideh Bagheri Novair, Behnam Asgari Lajayer and Eric D. van Hullebusch

Water 2021, 13(4), 517; doi:10.3390/w13040517

Article: Using Multi-Factor Analysis to Predict Urban Flood Depth Based on Naive Bayes

Huiliang Wang, Hongfa Wang, Zening Wu and Yihong Zhou

Water 2021, 13(4), 432; doi:10.3390/w13040432

Article: Study on Hydrologic Effects of Land Use Change Using a Distributed Hydrologic Model in the Dynamic Land Use Mode

Qingyan Sun, Chuiyu Lu, Hui Guo, Lingjia Yan, Xin He, Tao Qin, Chu Wu, Qinghua Luan, Bo Zhang and Zepeng Li

Water 2021, 13(4), 447; doi:10.3390/w13040447

Article: Distribution of Groundwater Arsenic in Uruguay Using Hybrid Machine Learning and Expert System Approaches

Ruohan Wu, Elena M. Alvareda, David A. Polya, Gonzalo Blanco and Pablo Gamazo

Water 2021, 13(4), 527; doi:10.3390/w13040527

Article: The U.S.-Mexico Transboundary Aquifer Assessment Program as a Model for Transborder Groundwater Collaboration

Elia M. Tapia-Villaseñor and Sharon B. Megdal

Water 2021, 13(4), 530; doi:10.3390/w13040530

Article: Inherent Safety Analysis and Sustainability Evaluation of Chitosan Production from Shrimp Exoskeleton in Colombia

Antonio Zuorro, Kariana Andrea Moreno-Sader and Ángel Darío González-Delgado

Water 2021, 13(4), 553; doi:10.3390/w13040553

Article: Evaluation of Groundwater Potential and Safe Yield of Heterogeneous Unconsolidated Aquifers in Chiang Mai Basin, Northern Thailand

Sutthipong Taweelarp, Morrakot Khebchareon and Schradh Saenton

Water 2021, 13(4), 558; doi:10.3390/w13040558

Hydrology and Hydrogeology

Review: An Overview of Flood Risk Analysis Methods

Daniel Constantin Diaconu, Romulus Costache and Mihnea Cristian Popa

Water 2021, 13(4), 474; doi:10.3390/w13040474

Review: Resilience in Complex Catchment Systems

Lindsay Beevers, Melissa Bedinger, Kerri McClymont and Annie Visser-Quinn

Water 2021, 13(4), 541; doi:10.3390/w13040541

Review: Salt Marsh Hydrogeology: A Review

Julia Guimond and Joseph Tamborski

Water 2021, 13(4), 543; doi:10.3390/w13040543

Article: Satellite Imageries and Field Data of Macrophytes Reveal a Regime Shift of a Tropical Lake (Lake Ziway, Ethiopia)

Yohannes Tefera Damtew, Boud Verbeiren, Aymere Awoke and Ludwig Triest

Water 2021, 13(4), 396; doi:10.3390/w13040396

Article: A Batch Experiment of Cesium Uptake Using Illitic Clays with Different Degrees of Crystallinity

Jeonghwan Hwang, Sungwook Choung, Woosik Shin, Weon Shik Han and Chul-Min Chon

Water 2021, 13(4), 409; doi:10.3390/w13040409

Article: Impact of Land Use Change on Non-Point Source Pollution in a Semi-Arid Catchment under Rapid Urbanisation in Bolivia

Benjamin Gossweiler, Ingrid Wesström, Ingmar Messing, Mauricio Villazón and Abraham Joel

Water 2021, 13(4), 410; doi:10.3390/w13040410

Article: Climate Change Adaptations for Food Security in Vulnerable Areas of the Egyptian Nile—For Tackling the Overlooked Nexus Hazards of Hydrological Extremes and Waste Pollutions

Otto Chen, Ahmed Abdelhalim, Ying Liu, Miguel Rico-Ramirez and Dawei Han

Water 2021, 13(4), 412; doi:10.3390/w13040412

Article: Assessing Stream-Aquifer Connectivity in a Coastal California Watershed

Bwalya Malama, Devin Pritchard-Peterson, John J. Jasbinsek and Christopher Surfleet

Water 2021, 13(4), 416; doi:10.3390/w13040416

Article: Impact of the Depth of Diaphragm Wall on the Groundwater Drawdown during Foundation Dewatering Considering Anisotropic Permeability of Aquifer

Xu-wei Wang and Ye-shuang Xu

Water 2021, 13(4), 418; doi:10.3390/w13040418

Article: A Case Study of Flood Risk Evaluation Based on Emergy Theory and Cloud Model in Anyang Region, China

Zening Wu, Yuhai Cui and Yuan Guo

Water 2021, 13(4), 420; doi:10.3390/w13040420

Article: Effect of Watershed Delineation and Climate Datasets Density on Runoff Predictions for the Upper Mississippi River Basin Using SWAT within HAWQS

Manyu Chen, Yuanlai Cui, Philip W. Gassman and Raghavan Srinivasan

Water 2021, 13(4), 422; doi:10.3390/w13040422

Article: Spatial Characteristics of Groundwater Chemistry in Unzen, Nagasaki, Japan

Kei Nakagawa, Hiroki Amano and Ronny Berndtsson

Water 2021, 13(4), 426; doi:10.3390/w13040426

Article: Regional-Scale Model Analysis of Climate Changes Impact on the Water Budget of the Critical Zone and Groundwater Recharge in the European Part of Russia

Sergey O. Grinevskiy, Sergey P. Pozdniakov and Ekaterina A. Dedulina

Water 2021, 13(4), 428; doi:10.3390/w13040428

Article: Assessment of the Impact of Small Hydropower Plants on the Ecological Status Indicators of Water Bodies: A Case Study in Lithuania

Laima Česonienė, Midona Dapkienė and Petras Punys

Water 2021, 13(4), 433; doi:10.3390/w13040433

Article: Deep Learning with Long Short Term Memory Based Sequence-to-Sequence Model for Rainfall-Runoff Simulation

Heechan Han, Changhyun Choi, Jaewon Jung and Hung Soo Kim

Water 2021, 13(4), 437; doi:10.3390/w13040437

Article: Formation Patterns of Mediterranean High-Mountain Water-Bodies in Sierra-Nevada, SE Spain

Jose Luis Diaz-Hernandez and Antonio Jose Herrera-Martinez

Water 2021, 13(4), 438; doi:10.3390/w13040438

Article: Estimation of Groundwater Evapotranspiration of Different Dominant Phreatophytes in the Mu Us Sandy Region

Wuhui Jia, Lihe Yin, Maosheng Zhang, Kun Yu, Luchen Wang and Fusheng Hu

Water 2021, 13(4), 440; doi:10.3390/w13040440

Article: Hydrogenotrophic Denitrification of Groundwater Using a Simplified Reactor for Drinking Water: A Case Study in the Kathmandu Valley, Nepal

Kenta Shinoda, Amit Kumar Maharjan, Rabin Maharjan, Tippawan Singhopon, Suphatchai Rujakom, Yuya Tsutsumi, Bijay Man Shakya, Tatsuru Kamei, Rawintra Eamrat and Futaba Kazama

Water 2021, 13(4), 444; doi:10.3390/w13040444

Article: Deriving Natural Background Levels of Arsenic at the Meso-Scale Using Site-Specific Datasets: An Unorthodox Method

Maria Filippini, Chiara Zanotti, Tullia Bonomi, Vito G. Sacchetti, Alessandro Amorosi, Enrico Dinelli and Marco Rotiroti

Water 2021, 13(4), 452; doi:10.3390/w13040452

Article: Analysis of Weakening Law and Stability of Sliding Zone Soil in Thrust-Load-Induced Accumulation Landslides Triggered by Rainfall Infiltration

Zhou Zhou, Junhui Shen, Song Tang, Weifeng Duan, Jingyong Wang, Richang Yang, Shengzhe Zheng and Fulin Guo

Water 2021, 13(4), 466; doi:10.3390/w13040466

Article: Simple Fully Automatic Testing Method of Seepage Indices for Low-Permeability Materials

Xizhong Shen, Ling Li and Yingjun Wang

Water 2021, 13(4), 477; doi:10.3390/w13040477

Article: Advantages of the Open Levee (Kasumi-Tei), a Traditional Japanese River Technology on the Matsuura River, from an Ecosystem-Based Disaster Risk Reduction Perspective

Jun Teramura and Yukihiro Shimatani

Water 2021, 13(4), 480; doi:10.3390/w13040480

Article: Modelling of the Discharge Response to Climate Change under RCP8.5 Scenario in the Alata River Basin (Mersin, SE Turkey)

Ümit Yıldırım, Cüneyt Güler, Barış Önol, Michael Rode and Seifeddine Jomaa

Water 2021, 13(4), 483; doi:10.3390/w13040483

Article: Nonstationary Ecological Instream Flow and Relevant Causes in the Huai River Basin, China

Qingzhi Wen, Peng Sun, Qiang Zhang and Hu Li

Water 2021, 13(4), 484; doi:10.3390/w13040484

Article: Rainfall-Induced Shallow Landslide Detachment, Transit and Runout Susceptibility Mapping by Integrating Machine Learning Techniques and GIS-Based Approaches

Mariano Di Napoli, Diego Di Martire, Giuseppe Bausilio, Domenico Calcaterra, Pierluigi Confuorto, Marco Firpo, Giacomo Pepe and Andrea Cevasco

Water 2021, 13(4), 488; doi:10.3390/w13040488

Article: Reconstructing Spatiotemporal Dynamics in Hydrological State Along Intermittent Rivers

Michael Eastman, Simon Parry, Catherine Sefton, Juhyun Park and Judy England

Water 2021, 13(4), 493; doi:10.3390/w13040493

Article: Influence of Intensive Agriculture on Benthic Macroinvertebrate Assemblages and Water Quality in the Aconcagua River Basin (Central Chile)

Pablo Fierro, Claudio Valdovinos, Carlos Lara and Gonzalo S. Saldías

Water 2021, 13(4), 492; doi:10.3390/w13040492

Article: Seasonal Variations of Dissolved Organic Matter by Fluorescent Analysis in a Typical River Catchment in Northern China

Zenglei Han, Min Xiao, Fujun Yue, Yuanbi Yi and K. M. G. Mostofa

Water 2021, 13(4), 494; doi:10.3390/w13040494

Article: The Detection of Flood Characteristics Alteration Induced by the Danjiangkou Reservoir at Han River, China

Xiao Zhang, Baofei Feng, Jun Zhang, Yinshan Xu, Jie Li, Wenjing Niu and Yanfei Yang

Water 2021, 13(4), 496; doi:10.3390/w13040496

Article: Integrating the JRC Monthly Water History Dataset and Geostatistical Analysis Approach to Quantify Surface Hydrological Connectivity Dynamics in an Ungauged Multi-Lake System

Lili Wu, Yueqing Chen, Guangxin Zhang, Y. Jun Xu and Zhiqiang Tan

Water 2021, 13(4), 497; doi:10.3390/w13040497

Article: The Terraces of the Anti-Atlas: From Abandonment to the Risk of Degradation of a Landscape Heritage

Mohamed Sabir

Water 2021, 13(4), 510; doi:10.3390/w13040510

Article: Controls on Streamflow Densities in Semiarid Rocky Mountain Catchments

Caroline Martin, Stephanie K. Kampf, John C. Hammond, Codie Wilson and Suzanne P. Anderson

Water 2021, 13(4), 521; doi:10.3390/w13040521

Article: The Development of a Framework for the Integrated Assessment of SDG Trade-Offs in the Sundarban Biosphere Reserve

Charlotte L. J. Marcinko, Robert J. Nicholls, Tim M. Daw, Sugata Hazra, Craig W. Hutton, Chris T. Hill, Derek Clarke, Andy Harfoot, Oindrila Basu, Isha Das, Sandip Giri, Sudipa Pal and Partho P. Mondal

Water 2021, 13(4), 528; doi:10.3390/w13040528

Article: A Planning Tool for Optimizing Investment to Reduce Drinking Water Risk to Multiple Water Treatment Plants in Open Catchments

Chris Thompson, Morag Stewart, Nick Marsh, Viet Phung and Thomas Lynn

Water 2021, 13(4), 531; doi:10.3390/w13040531

Article: Operational Implementation of Satellite-Rain Gauge Data Merging for Hydrological Modeling

Alejandra De Vera, Pablo Alfaro and Rafael Terra

Water 2021, 13(4), 533; doi:10.3390/w13040533

Article: Hydrogeochemical Characteristics and Processes of Shallow Groundwater in the Yellow River Delta, China

Chuanshun Zhi, Wengeng Cao, Zhuo Zhang, Zeyan Li and Yu Ren

Water 2021, 13(4), 534; doi:10.3390/w13040534

Article: Influence of Gully Land Consolidation on Phreatic Water Transformation in the Loess Hilly and Gully Region

Zihao Guo, Jianen Gao, Pengcheng Sun, Shaohui Dou, Juan Li, Xianyong Lou, Hong Wang, Rafiq Ahmad and Zhe Gao

Water 2021, 13(4), 538; doi:10.3390/w13040538

Article: Hydrochemical and Isotopic Characterization of the Waters of the Manglaralto River Basin (Ecuador) to Contribute to the Management of the Coastal Aquifer

Paúl Carrión-Mero, F. Javier Montalván, Fernando Morante-Carballo, Javier Heredia, F. Javier Elorza, Joselyne Solórzano and Héctor Aguilera

Water 2021, 13(4), 537; doi:10.3390/w13040537

Article: Quantification and Regionalization of the Interaction between the Doumen Reservoir and Regional Groundwater in the Urban Plains of Northwest China

Xiao Wang, Yicheng Geng, Weibo Zhou, Yun Li and Hao Luo

Water 2021, 13(4), 540; doi:10.3390/w13040540

Article: Prediction of Combined Terrestrial Evapotranspiration Index (CTEI) over Large River Basin Based on Machine Learning Approaches

Ahmed Elbeltagi, Nikul Kumari, Jaydeo K. Dharpure, Ali Mokhtar, Karam Alsafadi, Manish Kumar, Behrouz Mehdinejadiani, Hadi Ramezani Etedali, Youssef Brouziyne, Abu Reza Md. Towfiqul Islam and Alban Kuriqi

Water 2021, 13(4), 547; doi:10.3390/w13040547

Article: Stepwise Identification of Influencing Factors and Prediction of Typhoon Precipitation in Anhui Province Based on the Back Propagation Neural Network Model

Yuliang Zhou, Yang Li, Juliang Jin, Ping Zhou, Dong Zhang, Shaowei Ning and Yi Cui

Water 2021, 13(4), 550; doi:10.3390/w13040550

Article: Reliable Evapotranspiration Predictions with a Probabilistic Machine Learning Framework

Hakan Başağaoğlu, Debaditya Chakraborty and James Winterle

Water 2021, 13(4), 557; doi:10.3390/w13040557

Article: Trend Analyses of Baseflow and BFI for Undisturbed Watersheds in Michigan—Constraints from Multi-Objective Optimization

Benjamin Hagedorn and Christina Meadows

Water 2021, 13(4), 564; doi:10.3390/w13040564

Article: Deep Learning Framework with Time Series Analysis Methods for Runoff Prediction

Zhenghe Li, Kang Ling, Liwei Zhou and Modi Zhu

Water 2021, 13(4), 575; doi:10.3390/w13040575

Article: Assessing Multi-Hazard Vulnerability and Dynamic Coastal Flood Risk in the Mississippi Delta: The Global Delta Risk Index as a Social-Ecological Systems Approach

Carl C. Anderson, Fabrice G. Renaud, Michael Hagenlocher and John W. Day

Water 2021, 13(4), 577; doi:10.3390/w13040577

Article: Possible Sources of Salinity in the Upper Dibdibba Aquifer, Basrah, Iraq

Ahmed Abdulameer, Jassim Mohammed Thabit, Wael Kanoua, Oliver Wiche and Broder Merkel

Water 2021, 13(4), 578; doi:10.3390/w13040578

Communication: Rivers Try Harder. Reversed “Differential Erosion” as Geological Control of Flood in the Large Fluvial Systems in Poland

Jan Stefan Bihałowicz and Grzegorz Wierzbicki

Water 2021, 13(4), 424; doi:10.3390/w13040424

Editorial: Application of Stable Isotopes and Tritium in Hydrology

Ines Krajcar Bronić and Jadranka Barešić

Water 2021, 13(4), 430; doi:10.3390/w13040430

Editorial: Special Issue “Multiscale Impacts of Anthropogenic and Climate Changes on Tropical and Mediterranean Hydrology”

Gil Mahé, Luc Descroix, Alain Laraque, Olivier Ribolzi and Guillaume Lacombe

Water 2021, 13(4), 491; doi:10.3390/w13040491

 

Wastewater Treatment and Reuse

Review: Microbial Electrolysis Cells for Decentralised Wastewater Treatment: The Next Steps

Thomas Fudge, Isabella Bulmer, Kyle Bowman, Shangami Pathmakanthan, William Gambier, Zahir Dehouche, Sultan Majed Al-Salem and Achilleas Constantinou

Water 2021, 13(4), 445; doi:10.3390/w13040445

Review: Using Low Molecular Weight Organic Acids to Enhance Microbial Degradation of Polycyclic Aromatic Hydrocarbons: Current Understanding and Future Perspectives

Lei Zhang, Jie Qiao, Haiyang Cui, Minghui Wang and Xiujuan Li

Water 2021, 13(4), 446; doi:10.3390/w13040446

Article: Enhancement of Anaerobic Digestion of Waste-Activated Sludge by Conductive Materials under High Volatile Fatty Acids-to-Alkalinity Ratios

Paolo S. Calabrò, Filippo Fazzino, Carlo Limonti and Alessio Siciliano

Water 2021, 13(4), 391; doi:10.3390/w13040391

Article: Electrochemical/Peroxymonosulfate/NrGO-MnFe₂O₄ for Advanced Treatment of Landfill Leachate Nanofiltration Concentrate

Jiaqi Wang, Zhengguang He, Yuzhong Wang and Manjing Lu

Water 2021, 13(4), 413; doi:10.3390/w13040413

Article: Decentralized Domestic Sewage Treatment Using an Integrated Multi-Soil-Layering and Subsurface Wastewater Infiltration System

Dan Li, Xinze Wang, Lina Chi, Zhiping Zhang, Yanping Liu and Xueying Li

Water 2021, 13(4), 431; doi:10.3390/w13040431

Article: Use of the Zebra Mussel Dreissena polymorpha (Mollusca, Bivalvia) as a Bioindicator of Microplastics Pollution in Freshwater Ecosystems: A Case Study from Lake Iseo (North Italy)

Paolo Pastorino, Marino Prearo, Serena Anselmi, Vasco Menconi, Marco Bertoli, Alessandro Dondo, Elisabetta Pizzul and Monia Renzi

Water 2021, 13(4), 434; doi:10.3390/w13040434

Article: Gross Solids Content Prediction in Urban WWTPs Using SVM

Vanesa Mateo Pérez, José Manuel Mesa Fernández, Francisco Ortega Fernández and Joaquín Villanueva Balsera

Water 2021, 13(4), 442; doi:10.3390/w13040442

Article: Polycyclic Aromatic Hydrocarbons in Sediments from Typical Algae, Macrophyte Lake Bay and Adjoining River of Taihu Lake, China: Distribution, Sources, and Risk Assessment

Yibo Dong, Zaisheng Yan, Huifang Wu, Guoqing Zhang, Haichen Zhang and Mingzhong Yang

Water 2021, 13(4), 470; doi:10.3390/w13040470

Article: An Enhanced Electrocoagulation Process for the Removal of Fe and Mn from Municipal Wastewater Using Dielectrophoresis (DEP)

Abdulkarim Almukdad, Alaa H. Hawari and MhdAmmar Hafiz

Water 2021, 13(4), 485; doi:10.3390/w13040485

Article: Investigation and Optimization of Chitosan Performance in Flocculating Kaolin Suspensions Using a Real-Time Suspending Solid Concentration Measuring Method

Yan Xu, Kemin Gan, Siyi Liang, Haitao Liu and Qunhui Wang

Water 2021, 13(4), 513; doi:10.3390/w13040513

Article: Electrochemical Treatment of Effluent for the Removal of Contaminants of Emergent Concern and Culturable Microorganisms

Joana Dionísio, Cristiana Gonçalves, Paula Guedes, Alexandra B. Ribeiro and Nazaré Couto

Water 2021, 13(4), 520; doi:10.3390/w13040520

Article: Prospects in Cadmium-Contaminated Water Management Using Free-Living Cyanobacteria (Oscillatoria sp.)

Iván Carralero Bon, Lucas M. Salvatierra, Luciana D. Lario, Jordi Morató and Leonardo M. Pérez

Water 2021, 13(4), 542; doi:10.3390/w13040542

Article: Evaluation of Adsorption Mechanism of Chromium(VI) Ion Using Ni-Al Type and Ni-Al-Zr Type Hydroxides

Fumihiko Ogata, Noriaki Nagai, Ayako Tabuchi, Megumu Toda, Masashi Otani, Chalermpong Saenjum, Takehiro Nakamura and Naohito Kawasaki

Water 2021, 13(4), 551; doi:10.3390/w13040551

Article: Removal of Tetracycline Oxidation Products in the Nanofiltration Process

Renata Żyłła, Stanisław Ledakowicz, Tomasz Boruta, Magdalena Olak-Kucharczyk, Magdalena Foszpańczyk, Zdzisława Mrozińska and Jacek Balcerzak

Water 2021, 13(4), 555; doi:10.3390/w13040555

Article: Research about Organic Matter Removal and Biofilms Development of Pilot-Scale UV/H₂O₂-BAC Process

Wuchang Song, Congcong Li, Zhenqi Du, Jiangang Yue, Wenjun Sun, Lian Hou, Jianguang Liu and Ruibao Jia

Water 2021, 13(4), 565; doi:10.3390/w13040565

Article: Plant Nutrient Uptake in Full-Scale Floating Treatment Wetlands in a Florida Stormwater Pond: 2016–2020

Sarah A. White

Water 2021, 13(4), 569; doi:10.3390/w13040569

Article: Using Long Term Simulations to Understand Heat Transfer Processes during Steady Flow Conditions in Combined Sewers

Mohamad Abdel-Aal, Simon Tait, Mostafa Mohamed and Alma Schellart

Water 2021, 13(4), 570; doi:10.3390/w13040570

Correction: Correction: Wasielewski, S., et al. Evaluation of Different Clinoptilolite Zeolites as Adsorbent for Ammonium Removal from Highly Concentrated Synthetic Wastewater. Water 2018, 10, 584

Stephan Wasielewski, Eduard Rott, Ralf Minke and Heidrun Steinmetz

Water 2021, 13(4), 402; doi:10.3390/w13040402

Editorial: Removal of Pharmaceuticals from Water: Conventional and Alternative Treatments

Ricardo N. Coimbra, Carla Escapa and Marta Otero

Water 2021, 13(4), 487; doi:10.3390/w13040487

Editorial: Wastewater Treatment, Valorization, and Reuse

Mejdi Jeguirim and Salah Jellali

Water 2021, 13(4), 548; doi:10.3390/w13040548

Editorial: Urban and Industrial Wastewater Disinfection and Decontamination by Advanced Oxidation Processes (AOPs): Current Issues and Future Trends

Ana Rita Lado Ribeiro, Jorge Jesus Rodríguez-Chueca and Stefanos Giannakis

Water 2021, 13(4), 560; doi:10.3390/w13040560

Editorial: New Trends in Environmental Catalytic Technologies for Water Remediation

Zacharias Frontistis

Water 2021, 13(4), 571; doi:10.3390/w13040571

Water Resources Management, Policy and Governance

Review: Modelling Watershed and River Basin Processes in Cold Climate Regions: A Review

Junye Wang, Narayan Kumar Shrestha, Mojtaba Aghajani Delavar, Tesfa Worku Meshesha and Soumendra N. Bhanja

Water 2021, 13(4), 518; doi:10.3390/w13040518

Article: Clustering Simultaneous Occurrences of the Extreme Floods in the Neckar Catchment

Ehsan Modiri and András Bárdossy

Water 2021, 13(4), 399; doi:10.3390/w13040399

Article: An Operational High-Performance Forecasting System for City-Scale Pluvial Flash Floods in the Southwestern Plain Areas of Taiwan

Tzu-Yin Chang, Hongey Chen, Huei-Shuin Fu, Wei-Bo Chen, Yi-Chiang Yu, Wen-Ray Su and Lee-Yaw Lin

Water 2021, 13(4), 405; doi:10.3390/w13040405

Article: Emergy Analysis and Ecological Spillover as Tools to Quantify Ecological Compensation in Xuchang City, Qingyi River Basin, China

Huiqin Li, Cuimei Lv, Minhua Ling, Changkuan Gu, Yang Li, Zening Wu and Denghua Yan

Water 2021, 13(4), 414; doi:10.3390/w13040414

Article: Flow and Transport Numerical Model of a Coastal Aquifer Based on the Hydraulic Importance of a Dyke and Its Impact on Water Quality. Manglaralto—Ecuador

Paúl Carrión-Mero, F. Javier Montalván, Fernando Morante-Carballo, Carolina Loor-Flores de Valgas, Boris Apolo-Masache and Javier Heredia

Water 2021, 13(4), 443; doi:10.3390/w13040443

Article: A Computer Program to Support the Selection of Turbines to Recover Unused Energy at Hydraulic Networks

Ángel Mariano Rodríguez-Pérez, Inmaculada Pulido-Calvo and Pablo Cáceres-Ramos

Water 2021, 13(4), 467; doi:10.3390/w13040467

Article: Benthic Resource Baseline Mapping of Cakaunisasi and Yarawa Reef Ecosystem in the Ba Region of Fiji

Ashneel Ajay Singh, Anish Maharaj and Priyatma Singh

Water 2021, 13(4), 468; doi:10.3390/w13040468

Article: Analysis of Pore Water Pressure and Piping of Hydraulic Well

Jinman Kim, Heuisoo Han and Yoonhwa Jin

Water 2021, 13(4), 502; doi:10.3390/w13040502

Article: An Initial Framework for Understanding the Resilience of Aquifers to Groundwater Pumping

África de la Hera-Portillo, Julio López-Gutiérrez, Beatriz Mayor, Elena López-Gunn, Hans Jørgen Henriksen, Ryle Nørskov Gejl, Pedro Zorrilla-Miras and Pedro Martínez-Santos

Water 2021, 13(4), 519; doi:10.3390/w13040519

Article: Building the Treaty #3 Nibi Declaration Using an Anishinaabe Methodology of Ceremony, Language and Engagement

Aimée Craft and Lucas King

Water 2021, 13(4), 532; doi:10.3390/w13040532

Article: Towards Intangible Freshwater Cultural Ecosystem Services: Informing Sustainable Water Resources Management

Sikhululekile Ncube, Lindsay Beevers and Andrea Momblanch

Water 2021, 13(4), 535; doi:10.3390/w13040535

Article: A Forecast-Skill-Based Dynamic Pre-Storm Level Control for Reservoir Flood-Control Operation

Wenhua Wan, Xiaohui Lei, Jianshi Zhao, Mingna Wang, Soon-Thiam Khu and Chao Wang

Water 2021, 13(4), 556; doi:10.3390/w13040556

Article: Estimation of Soil Salt and Ion Contents Based on Hyperspectral Remote Sensing Data: A Case Study of Baidunzi Basin, China

Libing Wang, Bo Zhang, Qian Shen, Yue Yao, Shengyin Zhang, Huaidong Wei, Rongpeng Yao and Yaowen Zhang

Water 2021, 13(4), 559; doi:10.3390/w13040559

Article: Optimal Sizing of Rooftop Rainwater Harvesting Tanks for Sustainable Domestic Water Use in the West Bank, Palestine

Sameer Shadeed and Sandy Alawna

Water 2021, 13(4), 573; doi:10.3390/w13040573

 

Aquatic Systems—Quality and Contamination

Review: The Seagrass Holobiont: What We Know and What We Still Need to Disclose for Its Possible Use as an Ecological Indicator

Chiara Conte, Alice Rotini, Loredana Manfra, Marco Maria D’Andrea, Gidon Winters and Luciana Migliore

Water 2021, 13(4), 406; doi:10.3390/w13040406

Review: The Use of Constructed Wetland for Mitigating Nitrogen and Phosphorus from Agricultural Runoff: A Review

Jiayu Li, Bohong Zheng, Xiao Chen, Zhe Li, Qi Xia, Hua Wang, Yuan Yang, Yaoyu Zhou and Hong Yang

Water 2021, 13(4), 476; doi:10.3390/w13040476

Review: Benthic Diatoms in River Biomonitoring—Present and Future Perspectives within the Water Framework Directive

Andreas Masouras, Ioannis Karaouzas, Elias Dimitriou, George Tsirtsis and Evangelia Smeti

Water 2021, 13(4), 478; doi:10.3390/w13040478

Article: The Impact of Methane Seepage on the Pore-Water Geochemistry across the East Siberian Arctic Shelf

Natalia Guseva, Yulia Moiseeva, Darya Purgina, Elena Gershelis, Evgeniy Yakushev and Igor Semiletov

Water 2021, 13(4), 397; doi:10.3390/w13040397

Article: An Automated Approach to Groundwater Quality Monitoring—Geospatial Mapping Based on Combined Application of Gaussian Process Regression and Bayesian Information Criterion

Dmitrii Shadrin, Artyom Nikitin, Polina Tregubova, Vera Terekhova, Raghavendra Jana, Sergey Matveev and Maria Pukalchik

Water 2021, 13(4), 400; doi:10.3390/w13040400

Article: Effects of Acute Ammonia Stress on Antioxidant Responses, Histopathology and Ammonia Detoxification Metabolism in Triangle Sail Mussels (Hyriopsis cumingii)

Qianqian Zhao, Ke Feng, Lianbo Zhang, Yunpeng Bai and Weizhi Yao

Water 2021, 13(4), 425; doi:10.3390/w13040425

Article: Predicting Cyanobacterial Harmful Algal Blooms (CyanoHABs) in a Regulated River Using a Revised EFDC Model

Jung Min Ahn, Jungwook Kim, Lan Joo Park, Jihye Jeon, Jaehun Jong, Joong-Hyuk Min and Taegu Kang

Water 2021, 13(4), 439; doi:10.3390/w13040439

Article: Nutrient Load Mitigation with Wintertime Cover as Estimated by the INCA Model

Katri Rankinen, Eila Turtola, Riitta Lemola, Martyn Futter and José Enrique Cano Bernal

Water 2021, 13(4), 450; doi:10.3390/w13040450

Article: Fecal Contamination and High Nutrient Levels Pollute the Watersheds of Wujiang, China

Raju Sekar, Xin Jin, Shuang Liu, Jing Lu, Jianwei Shen, Yingya Zhou, Ziyang Gong, Xueying Feng, Shengjie Guo and Wenlong Li

Water 2021, 13(4), 457; doi:10.3390/w13040457

Article: Framework to Study the Effects of Climate Change on Vulnerability of Ecosystems and Societies: Case Study of Nitrates in Drinking Water in Southern Finland

Katri Rankinen, Maria Holmberg, Mikko Peltoniemi, Anu Akujärvi, Kati Anttila, Terhikki Manninen and Tiina Markkanen

Water 2021, 13(4), 472; doi:10.3390/w13040472

Article: Simulation of Pollution Load at Basin Scale Based on LSTM-BP Spatiotemporal Combination Model

Li Li, Yingjun Liu, Kang Wang and Dan Zhang

Water 2021, 13(4), 516; doi:10.3390/w13040516

Article: Identifying the Mechanisms behind the Positive Feedback Loop between Nitrogen Cycling and Algal Blooms in a Shallow Eutrophic Lake

Yu Yao, Huaji Liu, Ruiming Han, Dujun Li and Limin Zhang

Water 2021, 13(4), 524; doi:10.3390/w13040524

Article: Nitrogen Loss in Vegetable Field under the Simulated Rainfall Experiments in Hebei, China

Baoguo Ma, Ronghao Guan, Liang Liu, Zhixi Huang, Shuanwang Qi, Zengfu Xi, Ying Zhao, Shihao Song and Hong Yang

Water 2021, 13(4), 552; doi:10.3390/w13040552

Editorial: Water Quality Indices: Current and Future Trends in Evaluating Contamination of Groundwater Resources

Dimitrios E. Alexakis

Water 2021, 13(4), 401; doi:10.3390/w13040401

 

Urban Water Management

Review: Water Security in a Changing Environment: Concept, Challenges and Solutions

Binaya Kumar Mishra, Pankaj Kumar, Chitresh Saraswat, Shamik Chakraborty and Arjun Gautam

Water 2021, 13(4), 490; doi:10.3390/w13040490

Article: Campus Study of the Impact of Ultra-Low Flush Toilets on Sewerage Networks and Water Usage

Peter Melville-Shreeve, Sarah Cotterill, Alex Newman and David Butler

Water 2021, 13(4), 419; doi:10.3390/w13040419

Article: Towards a Solid Particle Hydrodynamic (SPH)-Based Solids Transport Model Applied to Ultra-Low Water Usage Sanitation in Developing Countries

Michael Gormley and Sophie MacLeod

Water 2021, 13(4), 441; doi:10.3390/w13040441

Article: Potential for Potable Water Savings Due to Rainwater Use in a Precast Concrete Factory

Giovanna Bertuzzi and Enedir Ghisi

Water 2021, 13(4), 448; doi:10.3390/w13040448

Article: Incomplete Mixing Model at Cross-Junctions in Epanet by Polynomial Equations

Daniel Hernández Cervantes, P. Amparo López-Jiménez, José Antonio Arciniega Nevárez, Xitlali Delgado Galván, Martín Rubén Jiménez Magaña, Modesto Pérez-Sánchez and José de Jesús Mora Rodríguez

Water 2021, 13(4), 453; doi:10.3390/w13040453

Article: Modeling Bacterial Regrowth and Trihalomethane Formation in Water Distribution Systems

Gopinathan R. Abhijith, Leonid Kadinski and Avi Ostfeld

Water 2021, 13(4), 463; doi:10.3390/w13040463

Article: Invertebrate and Microbial Response to Hyporheic Restoration of an Urban Stream

Sarah A. Morley, Linda D. Rhodes, Anne E. Baxter, Giles W. Goetz, Abigail H. Wells and Katherine D. Lynch

Water 2021, 13(4), 481; doi:10.3390/w13040481

Article: Seasonal Variation of Rainy and Dry Season Per Capita Water Consumption in Freetown City Sierra Leone

Salmatta Ibrahim A, Fayyaz Ali Memon and David Butler

Water 2021, 13(4), 499; doi:10.3390/w13040499

Article: Determination of Internal Elevation Fluctuation from CCTV Footage of Sanitary Sewers Using Deep Learning

Hyon Wook Ji, Sung Soo Yoo, Dan Daehyun Koo and Jeong-Hee Kang

Water 2021, 13(4), 503; doi:10.3390/w13040503

Article: Water Consumption Range Prediction in Huelva’s Households Using Classification and Regression Trees

Gustavo Bermejo-Martín, Carlos Rodríguez-Monroy and Yilsy M. Núñez-Guerrero

Water 2021, 13(4), 506; doi:10.3390/w13040506

Article: Water Quality-Based Double-Gates Control Strategy for Combined Sewer Overflows Pollution Control

Zhongqing Wei, Haidong Shangguan, Jiajun Zhan, Ruisheng Lin, Xiangfeng Huang, Lijun Lu, Huifeng Li, Banghao Du and Gongduan Fan

Water 2021, 13(4), 529; doi:10.3390/w13040529

Article: International Perceptions of Urban Blue-Green Infrastructure: A Comparison across Four Cities

Emily C. O’Donnell, Noelwah R. Netusil, Faith K. S. Chan, Nanco J. Dolman and Simon N. Gosling

Water 2021, 13(4), 544; doi:10.3390/w13040544

Article: Improving the Efficiency of Green Roofs Using Atmospheric Water Harvesting Systems (An Innovative Design)

Behrouz Pirouz, Stefania Anna Palermo and Michele Turco

Water 2021, 13(4), 546; doi:10.3390/w13040546

Article: Case Study for the Predictive Environmental Risk Assessment of Hexamethylenetetramine Release to the Yodo River during a Massive Tsunami Attack

Shogo Hamamoto, Lisa Ito, Nozomu Yoneyama and Akihiro Tokai

Water 2021, 13(4), 549; doi:10.3390/w13040549

Article: Water Supply Portfolio Planning and Policy Evaluation under Climate Change: A Case Study of Central Taiwan

Yen-Chen Huang, Chien-Ming Lee and Yue-Rong Hong

Water 2021, 13(4), 567; doi:10.3390/w13040567

Article: Understanding Public Acceptance of a Multifunctional Water Plaza: A Case Study

Leon Netzel, Emily Drewing, Louis Netzel and Martin Denecke

Water 2021, 13(4), 576; doi:10.3390/w13040576

Communication: Exposure to SARS-CoV-2 in Aerosolized Wastewater: Toilet Flushing, Wastewater Treatment, and Sprinkler Irrigation

Muhammad Usman, Muhammad Farooq, Muhammad Farooq and Ioannis Anastopoulos

Water 2021, 13(4), 436; doi:10.3390/w13040436

Editorial: Urbanization under a Changing Climate–Impacts on Hydrology

Caterina Valeo, Jianxun He and Kasiapillai S. Kasiviswanathan

Water 2021, 13(4), 393; doi:10.3390/w13040393

Editorial: Smart Urban Water Networks: Solutions, Trends and Challenges

Armando Di Nardo, Dominic L. Boccelli, Manuel Herrera, Enrico Creaco, Andrea Cominola, Robert Sitzenfrei and Riccardo Taormina

Water 2021, 13(4), 501; doi:10.3390/w13040501

Hydraulics and Hydrodynamics

Article: A Stochastic Procedure for Temporal Disaggregation of Daily Rainfall Data in SuDS Design

Matteo Pampaloni, Alvaro Sordo-Ward, Paola Bianucci, Ivan Gabriel-Martin, Enrica Caporali and Luis Garrote

Water 2021, 13(4), 403; doi:10.3390/w13040403

Article: Determination of Paleocurrent Directions Based on Well Logging Technology Aiming at the Lower Third Member of the Shahejie Formation in the Chezhen Depression and Its Implications

Yangjun Gao, Furong Li, Shilong Shi and Ye Chen

Water 2021, 13(4), 408; doi:10.3390/w13040408

Article: Effects of Wave-Induced Processes in a Coupled Wave–Ocean Model on Particle Transport Simulations

Joanna Staneva, Marcel Ricker, Ruben Carrasco Alvarez, Øyvind Breivik and Corinna Schrum

Water 2021, 13(4), 415; doi:10.3390/w13040415

Article: Experimental Study on the Optimal Strategy for Power Regulation of Governing System of Hydropower Station

Cong Wang, De-Kuan Wang and Jian-Ming Zhang

Water 2021, 13(4), 421; doi:10.3390/w13040421

Article: Deep Learning Method Based on Physics Informed Neural Network with Resnet Block for Solving Fluid Flow Problems

Chen Cheng and Guang-Tao Zhang

Water 2021, 13(4), 423; doi:10.3390/w13040423

Article: Unified Packing Model for Improved Prediction of Porosity and Hydraulic Conductivity of Binary Mixed Soils

Ammar El-Husseiny

Water 2021, 13(4), 455; doi:10.3390/w13040455

Article: Optimal Location of Energy Dissipation Box in Long Distance and High Drop Gravitational Water Supply System

Weixiang Ni, Jian Zhang and Sheng Chen

Water 2021, 13(4), 461; doi:10.3390/w13040461

Article: Methodology for Determining the Maximum Potentially Recoverable Energy in Water Distribution Networks

Elkin Duván Cubides-Castro, Carlos S. López-Aburto, Pedro L. Iglesias-Rey, F. Javier Martínez-Solano, Daniel Mora-Meliá and Marta Iglesias-Castelló

Water 2021, 13(4), 464; doi:10.3390/w13040464

Article: Turbulent Flow Structure in a Confluence: Influence of Tributaries Width and Discharge Ratios

Leila Alizadeh and João Fernandes

Water 2021, 13(4), 465; doi:10.3390/w13040465

Article: Mountain Road-Culvert Maintenance Algorithm

Vladimir Mandić, Miloš Šešlija, Slobodan Kolaković, Srđan Kolaković, Goran Jeftenić and Slaviša Trajković

Water 2021, 13(4), 471; doi:10.3390/w13040471

Article: Use of Fixed and Variable Speed Pumps in Water Distribution Networks with Different Control Strategies

Christian X. Briceño-León, Pedro L. Iglesias-Rey, F. Javier Martinez-Solano, Daniel Mora-Melia and Vicente S. Fuertes-Miquel

Water 2021, 13(4), 479; doi:10.3390/w13040479

Article: Model Based Assessment of the Reflection Behavior of Tidal Waves at Bathymetric Changes in Estuaries

Vanessa Sohrt, Sebastian S.V. Hein, Edgar Nehlsen, Thomas Strotmann and Peter Fröhle

Water 2021, 13(4), 489; doi:10.3390/w13040489

Article: Analysis of Unsteady Friction Models Used in Engineering Software for Water Hammer Analysis: Implementation Case in WANDA

Omar M. Abdeldayem, David Ferràs, Sam van der Zwan and Maria Kennedy

Water 2021, 13(4), 495; doi:10.3390/w13040495

Article: Three-Dimensional Flow of a Vortex Drop Shaft Spillway with an Elliptical Tangential Inlet

Zhou Yang, Jinbu Yin, Yangliang Lu, Zhiming Liu, Haoyu Yang and Genhai Xu

Water 2021, 13(4), 504; doi:10.3390/w13040504

Article: A System Dynamics Model of the Community-Based Rural Drinking Water Supply Program (PAMSIMAS) in Indonesia

D. Daniel, Julivius Prawira, Trimo Pamudji Al Djono, S. Subandriyo, Arya Rezagama and Aries Purwanto

Water 2021, 13(4), 507; doi:10.3390/w13040507

Article: Numerical Evaluation of Fractional Vertical Soil Water Flow Equations

Ali Ercan and M. Levent Kavvas

Water 2021, 13(4), 511; doi:10.3390/w13040511

Article: Inclusion of Hydraulic Controls in Rehabilitation Models of Drainage Networks to Control Floods

Leonardo Bayas-Jiménez, F. Javier Martínez-Solano, Pedro L. Iglesias-Rey, Daniel Mora-Melia and Vicente S. Fuertes-Miquel

Water 2021, 13(4), 514; doi:10.3390/w13040514

Article: Bridge Pier Scour under Ice Cover

Christopher Valela, Dario A. B. Sirianni, Ioan Nistor, Colin D. Rennie and Husham Almansour

Water 2021, 13(4), 536; doi:10.3390/w13040536

Article: Stream Flow Generation for Simulating Yearly Bed Change at an Ungauged Stream in Monsoon Region

Woong Hee Lee, Heung Sik Choi, Dongwoo Lee and Byungwoong Choi

Water 2021, 13(4), 554; doi:10.3390/w13040554

Article: Assessment of Renewal Priority of Water Pipeline Network against Earthquake Risk

Shogo Hamamoto, Lisa Ito and Akihiro Tokai

Water 2021, 13(4), 572; doi:10.3390/w13040572

 

Biodiversity and Ecosystem Functioning

Review: An Overview of Studies on Meiofaunal Traits of the Littoral Zone of Lakes

Marco Cifoni, Angela Boggero, Diana Maria Paola Galassi and Tiziana Di Lorenzo

Water 2021, 13(4), 473; doi:10.3390/w13040473

Review: Scientific Methods to Understand Fish Population Dynamics and Support Sustainable Fisheries Management

Shewit Gebremedhin, Stijn Bruneel, Abebe Getahun, Wassie Anteneh and Peter Goethals

Water 2021, 13(4), 574; doi:10.3390/w13040574

Article: Structural and Functional Variations of the Macrobenthic Community of the Adige Basin along the River Continuum

Mattias Gaglio, Vassilis Aschonitis, Alexandra Nicoleta Muresan, Fabio Vincenzi, Giuseppe Castaldelli and Elisa Anna Fano

Water 2021, 13(4), 451; doi:10.3390/w13040451

Article: Diversity and Structure of Pelagic Zooplankton (Crustacea, Rotifera) in NE Poland

Maciej Karpowicz and Jolanta Ejsmont-Karabin

Water 2021, 13(4), 456; doi:10.3390/w13040456

Article: How Does Mytilus galloprovincialis Respond When Exposed to the Gametophyte Phase of the Invasive Red Macroalga Asparagopsis armata Exudate?

Sónia D. Coelho, Hugo C. Vieira, Jacinta M. M. Oliveira, Sílvia F. S. Pires, Rui J. M. Rocha, Andreia C. M. Rodrigues, Amadeu M. V. M. Soares and Maria D. Bordalo

Water 2021, 13(4), 460; doi:10.3390/w13040460

Article: The First Insight into the Patterns of Size and Shape Variation of a Microcerberid Isopod

Jeongho Kim, Jaehyun Kim, Wonchoel Lee and Ivana Karanovic

Water 2021, 13(4), 515; doi:10.3390/w13040515

Article: Seasonal Response of Daphnia pulex to Cyanobacterial Extracts at Different Temperatures in Valle de Bravo Reservoir (Mexico)

S. Nandini, Carlos Sánchez-Zamora and S. S. S. Sarma

Water 2021, 13(4), 526; doi:10.3390/w13040526

Article: Late Holocene Peatland Evolution in Terelj and Tuul Rivers Drainage Basins in the Khentii Mountain Range of Northeastern Mongolia

Alexander Orkhonselenge, Munkhjargal Uuganzaya, Tuyagerel Davaagatan and Ganbaatar Enkhbayar

Water 2021, 13(4), 562; doi:10.3390/w13040562

 

Oceans and Coastal Zones

Article: Probabilistic Characterization of the Vegetated Hydrodynamic System Using Non-Parametric Bayesian Networks

Muhammad Hassan Khan Niazi, Oswaldo Morales Nápoles and Bregje K. van Wesenbeeck

Water 2021, 13(4), 398; doi:10.3390/w13040398

Article: Late Quaternary Landscape Dynamics at the La Spezia Gulf (NW Italy): A Multi-Proxy Approach Reveals Environmental Variability within a Rocky Embayment

Veronica Rossi, Alessandro Amorosi, Marco Marchesini, Silvia Marvelli, Andrea Cocchianella, Luca Lorenzini, Simon Luca Trigona, Gianfranco Valle and Monica Bini

Water 2021, 13(4), 427; doi:10.3390/w13040427

Article: Using Satellite Remote Sensing to Study the Effect of Sand Excavation on the Suspended Sediment in the Hong Kong-Zhuhai-Macau Bridge Region

Fenfen Liu, Tonghui Zhang, Haibin Ye and Shilin Tang

Water 2021, 13(4), 435; doi:10.3390/w13040435

Article: Industry-Driven versus Natural Groundwater Flow Regime at the Dead Sea Coastal Aquifer

Yehuda Levy and Haim Gvirtzman

Water 2021, 13(4), 498; doi:10.3390/w13040498

Article: Quantifying Uncertainty in Exposure to Coastal Hazards Associated with Both Climate Change and Adaptation Strategies: A U.S. Pacific Northwest Alternative Coastal Futures Analysis

Alexis K. Mills, Peter Ruggiero, John P. Bolte, Katherine A. Serafin and Eva Lipiec

Water 2021, 13(4), 545; doi:10.3390/w13040545

Article: Groundwater Monitoring Systems to Understand Sea Water Intrusion Dynamics in the Mediterranean: The Neretva Valley and the Southern Venice Coastal Aquifers Case Studies

Ivan Lovrinović, Alessandro Bergamasco, Veljko Srzić, Chiara Cavallina, Danko Holjević, Sandra Donnici, Joško Erceg, Luca Zaggia and Luigi Tosi

Water 2021, 13(4), 561; doi:10.3390/w13040561

Article: Phosphorous Supply to a Eutrophic Artificial Lake: Sedimentary versus Groundwater Sources

Wiebe Förster, Jan C. Scholten, Michael Schubert, Kay Knoeller, Nikolaus Classen, Michael Lechelt, Jan-Helge Richard, Udo Rohweder, Isabell Zunker and Susanne C. Wanner

Water 2021, 13(4), 563; doi:10.3390/w13040563

Editorial: Numerical and Data-Driven Modelling in Coastal, Hydrological and Hydraulic Engineering

Fangxin Fang

Water 2021, 13(4), 509; doi:10.3390/w13040509

 

Water Erosion and Sediment Transport

Article: Seasonal and Spatial Distribution and Pollution Assessment of Nitrogen and Phosphorus in Sediments from One of the World’s Largest Tidal Reservoirs

Yihao Shen, Cheng Peng, Peng Yuan, Xuefei Wu, Lei Jiang, Si Chen and Xinshan Song

Water 2021, 13(4), 395; doi:10.3390/w13040395

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Article: Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations

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Article: Semi-Rigid Erosion Control Techniques with Geotextiles Applied to Reservoir Margins in Hydroelectric Power Plants, Brazil

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Water 2021, 13(4), 500; doi:10.3390/w13040500

Article: Stable Carbon and Sulfur Isotope Characteristics of Stream Water in a Typical Karst Small Catchment, Southwest China

Yang Tang and Ruiyin Han

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Article: Controlling Factors of Badland Morphological Changes in the Emilia Apennines (Northern Italy)

Paola Coratza and Carlotta Parenti

Water 2021, 13(4), 539; doi:10.3390/w13040539

 

 

Water Use and Scarcity

Article: The Spatiotemporal Patterns and Interrelationships of Snow Cover and Climate Change in Tianshan Mountains

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Article: Assessing the Potential of Agricultural Reservoirs as the Source of Environmental Flow

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Article: Comparison of Multicriteria Decision-Making Techniques for Groundwater Recharge Potential Zonation: Case Study of the Willochra Basin, South Australia

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Water, Agriculture and Aquaculture

 

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Article: Strategies for Successful Scallops Spat Collection on Artificial Collectors in the Taranto Gulf (Mediterranean Sea)

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Weizhong Chen and Yan Chen

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Article: Can Irrigation Conditions Improve Farmers’ Subjective Well-being? An Investigation in Rural Pakistan

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Where Is the Bottom of a Watershed? Does It Matter?

Damned if I know the answers to those questions!

That's the title of a short paper I just stumbled upon - serendipity at work, as usual. It was published about a year ago:  

Condon, L. E., Markovich, K. H., Kelleher, C. A., McDonnell, J. J., Ferguson, G., & McIntosh, J. C. (2020). Where is the bottom of a watershed? Water Resources Research, 56, e2019WR026010. https://doi.org/ 10.1029/2019WR026010

Read it online here.

Download 2019WR026010

Key Points:

• Methods for defining the bottom of a watershed vary greatly across the hydrologic community

• Improved communication and collaborative efforts between the catchment hydrology and hydrogeology communities are needed

Abstract
Watersheds have served as one of our most basic units of organization in hydrology for over 300 years (Dooge, 1988, https://doi.org/10.1080/02626668809491223; McDonnell, 2017, https://doi.org/10.1038/ ngeo2964; Perrault, 1674, https://www.abebooks.com/first‐edition/lorigine‐fontaines‐Perrault‐Pierre‐Petit‐ Imprimeur/21599664536/bd). With growing interest in groundwater‐surface water interactions and subsurface flow paths, hydrologists are increasingly looking deeper. But the dialog between surface water hydrologists and groundwater hydrologists is still embryonic, and many basic questions are yet to be posed, let alone answered. One key question is: where is the bottom of a watershed? Knowing where to draw the bottom boundary has not yet been fully addressed in the literature, and how to define the watershed “bottom” is a fraught question. There is large variability across physical and conceptual models regarding how to implement a watershed bottom, and what counts as “deep” varies markedly in different communities. In this commentary, we seek to initiate a dialog on existing approaches to defining the bottom of the watershed. We briefly review the current literature describing how different communities typically frame the answer of just how deep we should look and identify situations where deep flow paths are key to developing realistic conceptual models of watershed systems. We then review the common conceptual approaches used to delineate the watershed lower boundary. Finally, we highlight opportunities to trigger this potential research area at the interface of catchment hydrology and hydrogeology.

1. On the Definition of Deep
Studies have demonstrated that groundwater is an important control on runoff generation (Buttle, 1994; Konikow & Leake, 2014; Tetzlaff et al., 2014; Zimmer & McGlynn, 2017), solute fluxes (Kirchner & Neal, 2013), transit time distributions (Hale & McDonnell, 2016; Maxwell et al., 2016; McGuire & McDonnell, 2006; Soulsby et al., 2006; Visser et al., 2019), ecohydrological processes (Fan, 2015; Horton et al., 2001; Koirala et al., 2017; Laio et al., 2009), and the behavior of earth system models (Clark et al., 2015; Krakauer et al., 2014). At the watershed (or catchment, used interchangeably here to refer to drainage basins) scale, nested local to regional groundwater flow paths emerge naturally from topography, and groundwater dis- charge is often a mix of shallow and deep flow paths (Figure 1). Yet the bulk of the effort to understand and represent groundwater interactions is limited to the shallowest part of the groundwater system. Catchment and land surface models commonly extend 2–3 m into the soil column and may exclude “deeper” storage or rely on a lumped approach to groundwater storage (Clark et al., 2015; Fan et al., 2019; Sellers et al., 1996). Recent critical zone (CZ) research extends deeper, generally looking tens of meters into the subsurface, while integrated groundwater‐surface water models tend to cover tens to hundreds of meter depth (Figure 1).

Although 100 m may sound deep as viewed by a catchment hydrologist, this is still less than the extent of many deep groundwater systems. Modern groundwater, as defined by the presence of tritium, is typically found at depths extending to 250 m (Gleeson et al., 2016). Similarly, active circulation of groundwater in mountain aquifers has been noted in the upper 100–200 m (Gleeson & Manning, 2008; Manning & Caine, 2007; Markovich, Manning, et al., 2019). We routinely pump groundwater for human usage from depths exceeding 100 m (Ferguson, McIntosh, Perrone, et al., 2018), and there are many examples of highly produc- tive agricultural regions that rely on deep groundwater systems (e.g., Scanlon et al., 2012).

Looking deeper, Pleistocene meteoric recharge has been found in both sedimentary and crystalline environ- ments at depths of up to 1,000 m (McIntosh et al., 2012). More recent work has characterized most groundwater at depths >250 m as pre‐Holocene in age (Jasechko et al., 2017). Groundwater discharge from these deep regional flow systems has been noted in the Colorado Plateau (Crossey et al., 2006) and the Western Canada Sedimentary Basin (Grasby & Betcher, 2002). Below a few thousand meters, most ground- waters are essentially stagnant over periods of millions of years due to a combination of low permeability (Ingebritsen & Manning, 1999; Warr et al., 2018) and negative buoyancy (Ferguson, McIntosh, Grasby, et al., 2018). The transition from fresh to saline groundwater generally occurs between 500 and 1,000 m (Ferguson, McIntosh, Perrone, et al., 2018). Nevertheless, deeper exceptions to these generalizations exist, particularly in mountainous regions where thermal springs with meteoric origins have circulation depths of up to 5,000 m (Ferguson & Grasby, 2011; Grasby & Hutcheon, 2001).

2. On the Importance of Going Deep
The fact that we can often observe modern groundwater hundreds of meters deep does not necessarily mean that every watershed study needs to extend to these depths. What defines a reasonable watershed bottom boundary will vary depending on the research questions, hydrogeologic setting, scale, available observations and computational resources (Ameli et al., 2018). As a first step, we advocate simply a critical assessment of whether “deep” flow paths (in this case referring to paths that extend deeper than one's current conceptual model) are potentially relevant in a particular place or to a given research question. To illustrate the potential importance of including deep flowpaths, we identify three cases where deep flow paths are key to developing a realistic conceptual model.

First, in places where deep flow paths contribute significantly to the catchment water balance, excluding these flow paths may lead to an incorrect formulation of the water balance or a fundamentally flawed con- ceptual model. Across larger river basins, Schaller and Fan (2009) and Fan (2019) challenged the commonly held view that catchments are closed systems, finding instead that many are regional groundwater importers or exporters. Similarly, multiple CZOs and other experimental sites operating at headwater scales have found that groundwater in fractured bedrock aquifers commonly contributes to streamflow (Brantley et al., 2017; Jin et al., 2011; Markovich, Dahlke, et al., 2019; McIntosh et al., 2017; Payn et al., 2012; White et al., 2019). Key to this discussion is the recent recognition that even at well‐studied sites, we are only begin- ning to detect that our “shallow views” on the hydrologic cycle may miss large fluxes of water or oversimplify our conceptual models of these systems. A recent study at the well‐studied Maimai catchment in New Zealand exemplifies this by demonstrating that deep groundwater, recharged in first‐order catchments, sub- sidizes flows to their parent watersheds (Ameli et al., 2018). This finding was all the more surprising consid- ering the super‐humid climate, steep topography, and low permeability bedrock—characteristics that are generally cited in shallow flowpath conceptualizations (Gleeson et al., 2011; Gleeson & Manning, 2008). A recent review by Fan (2019) suggests that such subsidies may be important in a range of watersheds settings.

Analysis of deep flow paths should not be limited to the natural interactions. Deep flow paths may be increasingly important where groundwater pumping and management operations are accessing ground- water, and connecting groundwater to the surface water budget through irrigation or other uses. Across the United States there is a trend of increasing well depth as wells are being drilled deeper to counter water scarcity (Perrone & Jasechko, 2019). This pumping represents a critical water supply for human activities but can have adverse environmental impacts. While it is well established that groundwater pumping can result in some stream capture (Konikow & Leake, 2014), recent, large‐scale modeling efforts have helped quantify the total impact that widespread groundwater pumping can have on the surface water budget (Condon & Maxwell, 2019; Konikow & Leake, 2014). Current human activities at depth may spell unknown future impacts for surface water quantity and quality. However, the treatment of hydrostratigraphy in many large‐scale watershed models remains simplistic and further work is needed to evaluate water quality at depth and the effects of pumping in deeper wells. Konikow and Leake (2014) note that deeper confined aqui- fers are less likely to result in capture of streamflow than pumping in shallower unconfined aquifers.

Second, even when deeper flowpaths contribute minimally to bulk discharge, they can still account for a dis- proportionate amount of solute fluxes. Rumsey et al. (2017) estimated that groundwater discharge to the Upper Colorado River accounted for 89% of the dissolved load in the river despite baseflow accounting for less than 44% of discharge at most gauges. While there was no attempt to determine the relative importance of groundwater and solute contributions from different depths in that study, the increase in salinity with depth typically observed in groundwater systems emphasizes the need to characterize deeper flowpaths to understand concentration‐discharge (C‐Q) relationships (Bluth & Kump, 1994; Grasby et al., 1999; Wymore et al., 2017). A deeper bottom boundary may also be necessary to capture legacy contamination. Van Meter et al. (2017) found that much of the nitrate in the Mississippi watershed was delivered as groundwater discharge. The depth of flowpaths was not explicitly explored in that study, but other regional studies in North America have found elevated nitrate concentrations to depths of up to 50 m (Mitchell et al., 2003; Nolan & Hitt, 2006; Rudolph et al., 2015).

Finally, deep flow paths are critical for characterizing the shape, and particularly the tails, of water residence time distributions (RTDs) and the transit time distributions (TTDs) of streamwater. While streamflow can be disproportionately fed by young (<3 months old) flowpaths (Berghuijs & Kirchner, 2017; Jasechko et al., 2016), analysis of transit times during low flow periods has shown the opposite—that substantially older flowpaths feed rivers during these times (>20 years; Gabrielli et al., 2018; Rademacher et al., 2005). Similarly, Maxwell et al. (2016) showed that topographically controlled groundwater systems can result in a larger diversity in subsurface flow paths and that groundwater configuration can control RTD shape. These shapes are linked to plant available water and streamflow generation. Exploring how Earth's CZ shapes deep groundwater flow pathways, groundwater RTD, and stream TTD remains a fundamental chal- lenge in the hydrologic sciences (Brooks et al., 2015).

Time to cut to the chase and skip to the end...

5. Summary and Vision for Moving Forward
This commentary highlights the disparate treatment of the watershed bottom across the hydrologic commu- nity. Though there are several paths forward, the first step may simply be a (vertical) shift in the depth we consider when building our conceptual models. We see three key opportunities to improve our representa- tions and understanding of this fundamental watershed characteristic:

1. Actually “observing” the bottom of a watershed remains a major challenge, but an important need. To this end, we need more observations at depth to characterize the vertical distribution of permeability. For example, CZ and other catchment studies often have too few wells below the interface of weathered and unweathered bedrock to adequately capture spatial variability of deep groundwater. There have been some advances in small borehole installation that have allowed for important discoveries related to residence time and active circulation depths in fractured rock systems (Gabrielli & McDonnell, 2012), but these generally extend to only 10 m or so. Additional deep well drilling and greater application of geophy- sical methods (e.g., White et al., 2019) are needed to provide spatial characterization of hydrostratigraphy down to 100–200 m. New 3‐D gridded datasets that make use of existing permeability data and data from a range of other sources are needed to improve modeling efforts at large scales.

2. We need new tools to characterize deep flow paths as well as the vertical storage and release of deep groundwater. The stable isotopes of hydrogen and oxygen have been workhorse tracers in water studies for decades. However, variability in flowpath lengths can be masked by similar isotopic signatures, and the tails of TTD may be truncated with these methods (Stewart et al., 2010). Collecting stable isotope data for both streamflow and precipitation with high frequency (e.g., von Freyberg et al., 2017) has led to insights in catchment response and is a novel area of development (Kirchner, 2019). Across the board, we advocate for additional tracer studies as well as the implementation of novel tracers, such as synthetic DNA (Dahlke et al., 2015), and tracers representing longer transit times, such as Argon‐39 (Loosli, 1983) to inform this important question.

3. Finally, we acknowledge that perfect information of subsurface architecture and permeability is probably unobtainable, especially outside heavily instrumented catchments. This means that we will always need to rely on numerical models of the subsurface. Within these numerical investigations, we need additional research to evaluate the sensitivity of simulated results to bottom boundary conceptualization and to characterize the systems and questions most sensitive to our representation and spatial configuration of the bottom. This is vital for large‐scale land surface and earth systems models where we are still iterating how best to represent the subsurface (Clark et al., 2015; Fan et al., 2019). We therefore advocate additional modeling and observational work across a more diverse set of sys- tems, including catchments in distinct climates (e.g., Tetzlaff et al., 2015), those with complex CZs (e.g., Buss et al., 2013; Hahm et al., 2019; Shi et al., 2013; Zimmer & McGlynn, 2017), and those experiencing human stressors and management (e.g., Bhaskar & Welty, 2015; Condon & Maxwell, 2019; McDonnell et al., 2018; Perrone & Jasechko, 2017; White et al., 2019).

   Above all, we need to critically interrogate our existing conceptual models of watershed systems and allow for more dialog on what the bottom of a watershed truly represents. Such interrogations may bring rethinking the water balance alongside our basic definition of watersheds into closer focus, accelerating the poten- tial for a new conceptual model of catchments to emerge. By improving our conceptualizations of this lower boundary, we are likely to bring hydrogeology and hydrology into closer contact, creating opportunities for the coevolution of knowledge and refining our perceptions of watershed functioning from a lateral as well as vertical lens—redefining watershed hydrology from the bottom‐up.

This is a thought-provoking paper. I have pondered this issue but have not investigated it to the degree the authors have. I was originally interested because of my desire to ensure that groundwater was considered in IWRM (integrated water resources management). My perception is that most IWRM practitioners treat watersheds (often the 'fundamental unit' in IWRM-based work) as two-dimensional entities (discounting the depth) and don't focus much on groundwater unless the source of water is predominantly groundwater from wells.     

Here's a classic flow diagram from Dr. Jozsef Toth: 

Does the depth to the bottom of the watershed matter? How about the bottom diagram:

I am not sure the depth of the above watershed matters. I guess it depends on your focus. 

The above graphics are not meant to suggest that I prefer 2D approaches. More to come on this interesting topic. Comments are welcomed!

Thanks to Condon et al. for the stimulation. 

Enjoy!

"When a man knows he is to be hanged in a fortnight, it concentrates his mind wonderfully." - Samuel Johnson

From RMSAWWA & RMWEA: How to Save the Colorado River and Other Tales

I just saw a copy of the November 2020 issue of the magazine Rocky Mountain Water, which is published by the Rocky Mountain Section of the AWWA and Rocky Mountain Water Environment Association. The issue has articles Impacts of Wildfires on Water Quality and Water Treatment (page 16) and How to Save the Colorado River (p. 25).

Download RMW__November_2020

Here is an electronic copy: click here.

I won't divulge the endings, but here is the last section of the Colorado River article.

Intuition vs. Facts

“The experiment is important to us,” Thompson said. “We want to make decisions based on the science and the data, not a gut feeling.”

Much of the work is grueling, like cutting hay samples week after week, and low tech, like measuring water levels in rain gauges.

But dramatic advances in satellite imagery and global evapotranspiration databases are helping people like Perry Cabot create science-based templates that eventually will be useful not just in Colorado, but Wyoming, Utah, New Mexico and perhaps even farther downstream, on cotton fields in Arizona and avocado groves in California’s Central Valley.

“We now have the ability to measure the whole field, ” Cabot said. “It’s becoming more accurate and it’s tremendously convenient if you’re trying to get a good understanding of patterns. We don’t have to rely on one data point anymore.” [Editor’s note: Cabot sits on the board of Water Education Colorado, which is a sponsor of Fresh Water News.]

Enjoy!

"He that will not apply new remedies must expect new evils." - Francis Bacon