Jan
11
The Aquadoc ‘Kiss of Death’: Dr. Robert M. Hirsch for USGS Director
January 11, 2009 | Posted by Michael "Aquadoc" Campana
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Okay, you’re saying - what do I have against USGS water maven Dr. Bob Hirsch? After all, my failures (so far) to get Peter Gleick appointed White House Water Advisor, Pat Mulroy named U.S. Bureau of Reclamation Commissioner, and Gerry Galloway selected as Assistant Secretary of the Army, Civil Works, are well-known.
I also wanted to see Gov. Bill Richardson (D-NM) as Secretary of State, but he is about to become a full-fledged Blago-boyich.
So I am extending my curse to Dr. Hirsch.
The current USGS Director, Dr. Mark Myers, just submitted his resignation, as is customary when a new administration takes the reins. He expressed an interest in staying as Director but has heard nothing. Dr. Suzette Kimball, Associate Director for Geology, is now the Acting Director.
So why Bob? If you’ve been reading my blog WaterWired, you know that I think very highly of him. I’ve posted about his “Big Four Water Issues” and more. There are few WaterWonks who know the Washington scene as well as Bob. I was disappointed to see him step down as USGS Associate Director for Water last spring, a post he held for 14 years. Here’s what I said then:
Bob has been an eloquent spokesman for USGS water programs lo these many years. He’s arguably the best-informed water scientist in the USA and the most astute observer of the “water scene”, especially from inside the Beltway (even though his office was in Reston, outside the Beltway).
In addition to knowing his way around DC, Bob has personally remained active “doing science”, no small task when you are an administrator of a government agency. He’s become an eloquent advocate for climate change research as related to water resources, something this country (and the world) must continue to address. He has also continued to speak out on the need for data, the lack of which will haunt us in the future.
His scientific abilities are well-respected, so he’s not viewed as just another lifelong bureaucrat with no science chops. Although the USGS is a proud scientific agency, Bob understands the science-policy interface. And he calls them as he sees them.
He’s also a WaterWonk.
President-elect Obama may wish to appoint someone younger (Bob’s probably my age), avoiding another OWG [Old White Guy]. A USGS outsider might also be viewed more favorably, and that vantage point certainly has merit. But in terms of someone who knows the ropes, is smart and respected, I can’t think of a better person than Dr. Bob Hirsch.
Who’s your choice?
“I don’t know the key to success, but the key to failure is trying to please everybody.” – Bill Cosby
[Disclosure notice: My institute receives about $93K annually from the USGS, just like the other 53 state water resources research institutes. The opinions expressed herein are mine alone.]
Jan
9
Podcast Archive: Riparian Ecosystems and Buffers - Working at the Water’s Edge (2008)
January 9, 2009 | Posted by admin
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| Opening Plenary - Keynote Speakers | |
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Rivers for Life Brian Richter, Nature Conservancy |
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Riparian Reflections James Karr, University of Washington |
| Tuesday Plenary - Keynote Speakers | |
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Trees,Streams and Water Quality: Making ConnectionsBernard Sweeney, Stroud Water Research Center |
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Old Approaches and New Challenges to Restoring River and Floodplain EcosystemsEmily Bernhardt, Department of Biology, Duke University |
| Closing Plenary - Keynote Speakers | |
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The Future Riparian Programs in USDA: Challenges and InnovationsMark Walbridge, USDA/ARS |
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Building Environmental Stewardship W. Tayloe Murphy, Jr., Former Secretary of Natural Resources for the Commonwealth of Virginia |
Jan
9
Podcast Archive: GIS and Water Resources V (2008)
January 9, 2009 | Posted by admin
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| OPENING PLENARY | |
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A Vision of the Future for California’s Sacramento/San Joaquin Delta: The Role of GIS, Visualation and Communication - Dr. Robert Twiss Robert Twiss, Professor of Environmental Planning Emeritus The University of California, Berkeley |
| SPECIAL SESSION: Past and Future of GIS and Water Resources | |
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Past and Future of GIS and Water ResourcesGuest Speakers: - David Maidment, University of Texas at Austin - David Tarboton, Utah State University - Steve Kopp - ESRI |
| SESSION 19: NHD/ArcHydro StreamStats | |
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StreamStats ArcGIS Server Web Application - Kernell Ries, U.S. Geological Survey, Baltimore, MD USA |
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Extending USGS StreamStats to Estimate Daily Precipitation and Temperature Time Series for Kentucky - Kenneth Odom, U.S. Geological Survey, Montgomery, AL USA (co-authors: John Guthrie, Lauren Hay, Mark Ayers) |
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A Desktop Application to Assess the Sustainable Basin Yields and Surface-Water Resources in Massachusetts - Pete Steeves, U.S. Geological Survey, Northboro, MA USA (co-author: Stacey A. Archfield) |
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Arc Hydro Tools for Determining Stream Slope - Kernell Ries, U.S. Geological Survey, Baltimore, MD USA (co-authors: Peter Steeves, Christine Dartiguenave) |
| SESSION 29: NHDPlus | |
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Introduction to NHDPlus and Developing Advanced Applications - Cindy McKay, Horizon Systems Corporation, Herndon, VA USA |
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National Hydrography Dataset Plus (NHDPlus) Applications Sampler - Tommy Dewald, U.S. Environmental Protection Agency - Office of Water, Washington, DC USA |
| Using the National Hydrography Dataset Plus (NHDPlus) in Arc Hydro - Alan Rea, U.S. Geological Survey, Boise, ID USA | |
| NHDPlus as the Core for Significant Nexus Analyses of Wetlands and Headwater Streams - William Cooter, RTI International, Durham, NC USA (co-authors: Jay Rineer; Brandon Bergenroth, Shel Brannan, Kevin Pickren, David Cunningham) | |
| SESSION 31: Hydrologic Information Systems - Modeling II | |
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Water Resources Modeling Using OpenMI-based Web Services - Jon Goodall, University of South Carolina, Columbia, SC USA (co-authors: Bella Robinson, Anthony Castronova, Fadi Shatnawi) |
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An OpenMI Model Interface Implementation for Hydrologic Modeling in an Open Source GIS - Daniel P. Ames, Idaho State University, Idaho Falls, ID USA (co-author: Harold Dunsford) |
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Guad2D: A Two-Dimensional Flow Model for Floodplain Mapping Over Time - Francisco Olivera, Texas A&M University, College Station, TX USA (co-authors: Martin Rodriguez, Javier Murillo) |
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Application of Independent GIS Programming in NCCHE Numerical Modeling System - Yaoxin Zhang, University of Mississippi, MS USA (co-authors: Yafei Jia, Sam S.Y. Wang) |
Jan
9
Podcast Archive: 2007 Annual Conference
January 9, 2009 | Posted by admin
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NOTE: Due to varying recording conditions, record volume and quality may vary from one recording to the next. Additional recordings should follow shortly.
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Luncheon Speaker: Honorable Jackie Dingfelder - Oregon House of Representatives - Bridging the Gap Between Science and Policy: A Legislative Perspective |
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Plenary Speaker: Cynthia Barnett - Journalist Gainesville, FL - MIRAGE: Florida and the Vanishing Water of the Eastern USA |
Jan
9
Water Strategy for the USA: Op-Ed by Jim Thebaut and Erik Webb
January 9, 2009 | Posted by Michael "Aquadoc" Campana
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A Water Strategy for the United States
By Jim Thebaut and Erik Webb
Those Americans even aware of Zimbabwe’s recent fight against the disruption and death caused by cholera, a highly treatable water-borne disease, carry an unfounded confidence that clean, abundant water will always be available and a similar water-borne disease epidemic could never occur here. However, many areas of our nation aren’t far from the conditions facing third-world countries in ensuring adequate, clean drinking water for their people. Various regions of our country face problems including dwindling surface and groundwater supplies, non-existent water and sanitation infrastructure, closely packed septic systems, inadequate reinvestment in existing water treatment infrastructure, and expanding contamination of surface water including both biological and new chemicals (including pharmaceuticals) that all increase our risk of water-borne illness outbreaks.
Like the proverbial frog in slowly heated water, we are rapidly reaching crisis levels without truly being aware of the risks. This crisis is curable if the United States chooses to establish a modern, integrated, national water policy framework, implements sustainable water use planning, invests in the changes needed to pursue water resource sustainability, and provides leadership to assist the rest of the world meet similar goals.
The region of the country closest to the breaking point is the Colorado River basin, which provides drinking water for 30 million people in the American Southwest. Although most of the region’s residents still have adequate, untainted water, portions of the Navajo and Hopi reservation communities of Arizona, New Mexico, Utah and Colorado – about 80,000 people – live with inadequate plumbing and sanitation and regularly drink untreated water. This portion of the Native American population suffers from birth defects and skin diseases out of proportion to the rest of the country. Additionally, it is anticipated that as climate change causes rising water temperatures greater disease risk will occur.
Creating plentiful, clean water for the Southwest’s Native Americans is one small part of a bigger picture. Similar water supply and sanitation challenges are emerging throughout the nation. Over two thirds of state’s chief water managers anticipate drought and other water crisis in the near future. Infrastructure investment is grossly inadequate to maintain current systems, let alone meet the demand anticipated by another 100 million people over the next 3-4 decades.
We’ve faced these issues before and started down a path of coordinated policies. In the post-World War II era, the nation faced a decade of drought that triggered intense national pressure to coordinate expansion of water supplies. Congressional committees and White House offices were coordinated in order to address water supply issues allowing water development to proceed at an accelerated pace. We then realized and began to face the environmental consequences of expansion with greater national emphasis on protection of natural resources. Unfortunately, while addressing environmental issues our over-reaction to development allowed us to sweep away the essential coordination functions embodied in the White House Water Resources Council. The consequence is that our nation’s water policy has devolved into a tangled mess of competing initiatives and policies intended to govern increasing demands, managing runoff, pollution abatement, improving quality, using reservoirs and underground water storage, conservation and efficiency improvements, all overseen by a complex infrastructure of federal, state and local bureaus, departments and agencies with overlapping and competing responsibilities. As a result, we have a hodgepodge of laws and regulations that benefit some at the expense of others. At best, our nation’s water use and planning structure is fractured and inefficient. At worst, it’s headed for complete breakdown.
Presently, at the federal level alone, 20 agencies and bureaus, under six cabinet departments, directed by 13 congressional committees with 23 subcommittees and five appropriations subcommittees are responsible for water-resource management. Consolidation of these responsibilities would make the job of managing water resources easier, but such consolidation of power and control is unlikely. A more likely approach might involve White House coordination of partnerships between federal agencies and coordination with state and local agencies to create integrated water policies as part of a national framework.
Additionally, decision-makers at every level must learn to embrace the principles of integrated water resources management, the concept of considering multiple viewpoints before making decisions. While this practice is gaining acceptance and application, it is woefully under-used in our highly fractionated U.S. water management system.
Integrated management would be based on clear principles. For example, as a nation, we must begin to treat water as we would any other scarce resource and learn to live within our means. This requires efficiency and planning for sustainable use in the face of increasing demands for water, particularly in agriculture, industry and power production.
One of the best ways to promote sustainability is to make consumers aware of the true cost of water. What we pay to the water company each month only reflects the price to bring clean water to our taps and does not reflect the value of the resource in each of its various uses. Water management, resource expansion, environmental protection, and infrastructure maintenance is expensive, and much of the cost is redistributed through state and federal taxes and local and regional bond measures. Transparency about the real cost of water should be a fundamental principle, irrespective of the source of funds that underwrite the supply.
The good news is that the United States has experience with integrating national water policy. The Water Resources Planning Act of 1965 created the Water Resources Council, empowered to assess the adequacy of the nation’s water supplies, to establish principles and standards for federal participants in water projects, and to review agricultural, urban, energy, industrial, recreational and fish and wildlife water needs. The Act also established a grant program to assist state development of comprehensive water and land use plans. This law was passed in an era before we understood the full environmental impact of our water resource management actions, and therefore needs to be strengthened to be effective. Nevertheless, the law creating the Council was never repealed.
It is now time that we re-empower and revise the Act to coordinate the nation’s efforts toward sustainable water resources development.
This revision could benefit by incorporating the much stronger policy framework for international water policy objectives embodied in the Senator Paul Simon Water for the Poor Act, signed into law in late 2005, which establishes access to safe water and sanitation as a major U.S. foreign policy objective. Merging our domestic and international water policy framework, and placing its operation directly under the umbrella of the White House, would unite and organize our national and international efforts and help solve both domestic and international water problems.
When it comes to drinking water, our nation and the planet are clearly at a crossroads. Ensuring each member of our nation and the world community access to clean water is a humanitarian mission that will assure a safer world and avoid environmental calamity. Population growth, increased demands and changes in our hydrological systems caused by climate change make addressing the water crisis an imperative. The United States can assume global leadership by setting a viable example in solving our own drinking water and sanitation issues, finding a viable way to coordinate our national water policy, and coupling our domestic efforts with our international policy.
Download Thebaut-National Water Policy oped
Jim Thebaut is the writer, director and executive producer of public television’s “The American Southwest: Are We Running Dry?” and “Running Dry,” a documentary about the global water crisis. Erik Webb is a PhD hydrologist at Sandia National Laboratories in New Mexico and a former Congressional Fellow with the Senate Energy and Natural Resources Committee.
Note: Jim sent this to me. Both Jim and Erik are good friends of mine. After Peter Gleick, Erik would be my choice as White House Water Advisor. He formerly was Sen. Pete Domenici’s (R-NM) water and energy advisor.
Jan
9
Podcast Archive: Emerging Contaminants of Concern in the Environment (2007)
January 9, 2009 | Posted by admin
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NOTE: Due to varying recording conditions, record volume and quality may vary from one recording to the next.
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Gerry Galloway - Opening Remarks |
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Plenary Speaker: Christian Daughton, USEPA
“PPCPS in the Environment: An Overview of the Science” |
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Plenary Speaker: Kim Linton, AWWARF
“Drinking Water Research on Trace Organics |
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Plenary Speaker: Theo Colborn, University of Florida-Gainesville
“Emerging Public Health Issues: Stealth Chemicals and Water Resources” |
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Plenary Speaker: Dana Kolpin, USGS
“Emerging Contaminants: Understanding Their Occurence, Fate and Effects |
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Plenary Speaker: Harold Zenick, NHEERL/ORD
“An Overview of the Interagency Pharmaceuticals in the Environment Working Group” |
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Plenary Speaker: Peter Stoks, Association of Rhine Water Works, Nieuwegein, Norway
“The EU Water Framework of Directive: Ecology Versus Drinking Water Production |
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Plenary Speaker - Rula Deeb, Malcolm Pirnie, Inc.
“Trace Organic Compounds in the Environment: Overview of the WERF Program Challenge and Research Needs |
Jan
9
Podcast Archive: Third Water Resources Policy Dialogue (2007)
January 9, 2009 | Posted by admin
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DIALOGUE DAY # 1 |
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| Dialogue Opening Remarks | |
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Richard A. Engberg - Opening Remarks |
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Gerry Galloway - Opening Remarks |
| Panel 1 - Federal Agency Perspectives on Water Policy | |
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Robert M. Hirsch - US Geological Survey |
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Benjamin H. Grumbles - US Environmental Protection Agency |
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Arlen Lancaster - Natural Resources Conservation Service |
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LTG Carl A. Strock - US Army Corps of Engineers |
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Ken Stansell - US Fish and Wildlife Service |
| Theme #1 Setting a Direction - Reconciling the Current Ad Hoc “National” Water Policy | |
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Theme #1 Keynote: The Honorable Congress John Linder |
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Steven McCormick - Nature Conservancy |
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Kathleen McGinty - Pennsylvania Dept. of Environmental Quality |
| Day 1: Luncheon | |
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Luncheon Speaker: David Maurstand - U.S. EPA, Director, FEMA Mitigation Division “National Flood Risk Reduction Policy Issues and Challenges” |
| Theme #2: Working Together Holistically: Multidisciplinary Approaches to Water Resources Issues Using Collaboration | |
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Theme 2: Keynote: Congressman Earl Blumenauer |
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Thought Leader: George Kuper - Council of Great Lakes Industries |
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Thought Leader: Jeffrery Kigthlinger - Metropolitan Water District of Southern California |
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Theme #2: Q&A Session |
DIALOGUE DAY # 2 |
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| Panel 2: Federal Agency Perspective on Water Policy | |
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Robert Quint - US Bureau of Reclamation |
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Joel Holtrop - US Forest Service |
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Michael Buckley - Federal Emergency Management Agency |
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Pedro Restrepo - NOAA-National Weather Service |
| Theme #3: Building on Science - The Need for Good Science to Support Sound Policy Decisions | |
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The Honorable Mike Johanns - Keynote Speaker - Secretary of Agriculture |
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Thought Leader: Robert Perciasepe - National Audubon Society |
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Thought Leader: Donald F. Boesch - University of Maryland Center for Environmental Science |
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Thought Leader: Erik Webb - Office of Senator Pete Domenici |
| Day 2: Luncheon | |
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Luncheon Speaker: The Honorable John Paul Woodley, Jr., Assistant Secretary of the Army for Civil Works |
| Provocateur Presentations - How I See the Issues and the Discussions | |
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Provocateur: Terry Williams - Northwest Tribes |
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Provocateur: G. Tracy Mehan |
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Provocateur: Daniel P. Beard - Dan Beard Consulting |
Jan
9
Challenges and Opportunities
January 9, 2009 | Posted by admin
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Jerry Sehlke, President AWRA
It seems that with every presidential election and inauguration we hear about how important this election is and how critical the issues are facing us this election cycle. And each time it is probably true. However, it is undeniable that we are presently facing many monumental challenges. These include a world-wide economic crisis, energy challenges, climate change, a major reduction in the scientific workforce due to the retirement of the baby boomers, and an apparently growing lack of faith in traditional institutions, including scientific institutions, to name a few. To many it seems that the world is in chaos. However, according to the old Chinese proverb, “out of chaos comes opportunity.” I believe that this is true, at least to those who are prepared to take advantage of those potential opportunities.
As we start this New Year I believe we should survey the challenges and the opportunities that are before us and we as AWRA members, staff and board should ask ourselves; do we understand the critical issues that are facing us and are we prepared to help prioritize and solve them? I don’t expect that we as a water-resources community hold the key to solving the world-wide economic meltdown or our seemingly insatiable appetite for energy, but do we understand the potential impacts of them on the water resources field? Do we know the depth and the potential impacts of the impending baby boomer retirement on the water resources field and what we need to do to train up a new generation of scientists? Are we developing a plan and a mechanism to transfer our historical knowledge and experience to the next generation such that our field will not only be able to carry on, but it will be able to continue building on that historical knowledge and experience?
More so than just developing an understanding, are we actively working together as an association and with other water resources associations to address the critical challenges within our field? Are we helping inform the appropriate decision makers and institutions about the challenges we are or will soon be facing in our field and are we helping them develop sensible, long-term, holistic solutions to those challenges? And are we conducting and presenting our research to the highest degree of quality and transparency possible, such that those who read and utilize our research will have faith in that we as a scientific institution/profession can be and should be trusted?
I feel very blessed by the opportunity to help lead the AWRA that you have bestowed upon me. I am somewhat daunted by the challenges that we face both as an organization and as a society, but I am enthralled with the potential opportunities that present themselves. I am thankful for the great membership, staff and board-leadership that we have within the AWRA. I am especially thankful for the great tutelage I have received thus far from Ken and the staff, and great leaders like our past presidents Jane Rowan and Gerry Galloway. I hope that all that you and they have taught and otherwise imparted to me over the years has prepared me for the wonderful opportunity and the great responsibility that you have given me. And I look forward to working with each of you to maintain and to expand AWRA’s leadership role in understanding and solving the critical challenges that face the water resources field in the future.
Jan
8
Southwest Hydrology: ‘Dear Mr. President and Members of Congress’
January 8, 2009 | Posted by Michael "Aquadoc" Campana
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The January-February 2009 issue of Southwest Hydrology has hit the streets and it’s a real special issue - advice to President Obama and the new Congress from some of the country’s foremost water experts.
From the WWW site:
January 2009 brings the inauguration of a new President and many new members of Congress. They and the continuing members of Congress will need to address serious water issues facing the country, especially in the West. Infrastructure is crumbling. Water quality is becoming worse in many areas. Climate change is impacting our hydrologic systems in completely new ways. We must conserve more water, and we must act sooner rather than later. Several of the country’s foremost water experts share their thoughts on how the federal government could most efficiently and effectively face this imminent threat to our health, welfare, economy, and national security.
You can download the entire issue or individual articles for free.
Some of the experts and articles featured:
Critical Need: A National Interagency Water Plan, by Brad Udall and Kristen Averyt
Doing More with Less: Improving Water Use Efficiency Nationwide, by Peter Gleick
Pharmaceuticals in Water: Implications for Sustainability, by Shane A. Snyder
Keep the West Vibrant with a Strong Climate Change Policy, by Jonathan Overpeck
Taking Care of Infrastructure Business, by Gerald E. Galloway
Short-Term Improvements for Water Management in the West, by William A. Blomquist and Jeffrey J. Mosher
“Facts do not cease to exist just because they are ignored.” – Aldous Huxley
Jan
7
IMPACT Article: Presenting Urban Stormwater BMP Performance Data to a Broad Audience
January 7, 2009 | Posted by admin
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Authors
John Kosco and Nikos Singelis
INTRODUCTION
Accurate data on stormwater best management practice (BMP) performance is important for many reasons. Engineers use BMP performance data to estimate effectiveness and meet design requirements. Municipal officials use BMP performance data to assess whether a particular design will meet local requirements. State and local water quality professionals use BMP performance data to estimate whether selected BMPs will remove enough discharged pollutants that impair waterbodies. National Pollutant Discharge Elimination System (NPDES) permit writers use BMP performance data to require more effective controls in permits.
However, stormwater BMP performance information has been difficult to summarize and present to these audiences because of the complexity associated with monitoring stormwater BMPs. Unlike the monitoring of a traditional point source such as a wastewater treatment plant, which has a fairly consistent flow and quality, a stormwater BMP is monitored only during or just after a storm. The intermittent discharges associated with storms introduce wide variability in water quantity and quality making accurate sampling of the BMP’s effectiveness more difficult.
The U.S. Environmental Protection Agency (USEPA) has created a web-based tool, the Urban BMP Performance Tool (available at www.epa.gov/npdes/urbanbmptool), to provide stormwater professionals with easy access to research studies on the performance of stormwater BMPs. This tool can be used to search BMPs to identify pollutant removal and stormwater volume reduction information. However, in order to effectively use the tool, stormwater professionals must have a basic understanding of the factors that influence BMP performance. This article describes those factors, including stormwater pollutant load reductions, stormwater volume reductions, and why percent removal is a misleading indicator of BMP performance.
WHAT FACTORS INFLUENCE THE PERFORMANCE OF BMPS IN THE REAL WORLD?
Defining the performance of BMPs is not an exact science. BMPs, unlike other treatment technologies – such as those used in wastewater treatment systems – are not static systems that deliver constant or even predictable results. The performance of stormwater BMPs is significantly influenced by such factors as design, installation, rainfall patterns and characteristics, soil types, slopes, land use in the drainage area, and age of the system, to name a few. Figure 1 illustrates the variability of BMP performance in removing total suspended solids. For example, detention ponds achieve a median effluent quality of 26.7 mg/l, but effluent quality can range from 16.7 to 44.9 mg/l depending on various factors.
Choosing effective BMPs is a significant challenge for all of us in the stormwater community … fortunately, tools, backed by reliable scientific studies, are emerging that will help us improve the process of choosing better BMPs
One important piece of advice is … Don’t latch on to one number and expect a stormwater BMP to deliver that level of performance each and every time. While we can’t now, and might not ever, be able to predict BMP performance with 100% accuracy, we do have – as a result of the diligent efforts of hundreds of researchers and practitioners – information that will help us detect trends in BMP performance.
“STORMWATER URBAN MYTH:” PERCENT REMOVAL
Spend any time at all discussing BMP performance or looking at articles and studies and you are soon going to encounter the concept of “percent removal.” This widely (mis)used concept, which may also be called percent effectiveness or other names, uses an influent and effluent concentration to obtain the percent reduction between the two.
Experts in the field of BMP performance, including those at USEPA, find this measure more misleading than helpful. Among the many reasons to avoid this measure is that by relying on just one percentage value, we lose the context of the conditions from which it was derived. For instance, the influent in one study may have been particularly dirty, in another significantly less so. Looking at the percentage alone does not provide us with that information. In fact, percent removals are highly influenced by how dirty the site (influent) is and don’t tell us much about how well the BMP actually worked. For example, Figure 2 shows that a BMP receiving 100 mg/l influent that removed 80% of the pollutant will achieve 20 mg/l effluent concentration. However, a second BMP with a cleaner influent (20 mg/l), and lower percent removal (50%), could achieve a better water quality result (10 mg/l). If decisions are based only on percent removal, an engineer may end up choosing the wrong BMP for their site. You can find an excellent article on this subject by Jonathan Jones, Jane Clary, Eric Strecker, and Marcus Quigley in the January/February 2008 issue of Stormwater magazine (www.stormh2o.com).
TOTAL LOAD REDUCTION
Rather than relying on a percentage to describe BMP performance, you should consider several factors, including event mean concentrations (EMCs), volume reduction information (discussed next), and total load reduction. If you would like to compare the performance of BMPs across types, one of the better ways to do this would be to compare total load reduction. A load reduction measure takes into account both the volume of stormwater coming into and leaving the BMP as well as the concentration of pollutants. Using a load reduction measure (usually pounds or kilograms) becomes particularly relevant when examining BMPs that reduce the volume of stormwater. Figure 3 illustrates the concept of examining pollutant reduction potential by looking at a load reduction measure. In this example, you can see that calculating a simple “percent removal” using the concentration numbers (e.g., beakers) would result in a 50% reduction of the pollutant while using the total load results in a 75% reduction. The 50% removal number is misleading because it does not account for the large volume of stormwater infiltrated by the BMP. It is only when we look at total load reduction that we see the true performance of the BMP.
IMPORTANCE OF VOLUME REDUCTION
As we learn more about the relationship between urban and suburban development and watershed health, it becomes clear that one of the major factors affecting the condition of our rivers, lakes, coastal waters and wetlands is the increased volume and velocity of stormwater runoff reaching these waterbodies. As we add impervious surfaces (including roads, driveways, homes, shopping malls and all of the other facets of urbanization) to our watersheds, we create changes in how these watersheds function hydrologically. Increases in impervious surfaces result in increases in stormwater flowing off the land and corresponding reductions in the rain and snow melt that would otherwise soak into the ground. These changes can have profound impacts on many of our waters, particularly sensitive headwater streams, wetlands, and small lakes. Much has been written elsewhere on this topic. The key message is that when planning and designing systems to manage urban stormwater, we need to carefully weigh options that encourage infiltration of stormwater and help to maintain or restore the natural hydrologic balance of the land that is being developed. Another important point to keep in mind (and can clearly been seen in the Figure 3) is that when we choose stormwater BMPs that reduce the volume of stormwater we also reduce the load of the pollutants entering surface waters.
OTHER FACTORS TO CONSIDER WHEN SELECTING BMPS
Obviously, pollutant and volume reduction potential are two key considerations we should always keep in mind when selecting or approving stormwater BMPs. There are many other considerations which also have a role in BMP selection. Costs are always a significant factor. Total capital costs (e.g., cost of installation), as well as factors such as cost per acre treated, can provide valuable information. Another cost-related factor that is frequently overlooked is the cost of maintenance of the BMP over the long term. All BMPs require regular, and sometimes frequent, maintenance. Considering ease of maintenance and overall maintenance costs should help inform our choices. Other factors to consider include the function of the BMP in regional drainage and flood management efforts and whether the BMP has “secondary” benefits, including habitat values, carbon sequestration, and water conservation, among others. Aesthetics and public acceptance are also very important, as is the longevity or useful life of the BMP. Of course, everyone involved in stormwater management also needs to consider and mitigate any potential safety issues.
USEPA’S URBAN BMP PERFORMANCE TOOL
So, how do you select a “better” BMP for your site? In January 2008, USEPA released the Urban Stormwater BMP Performance Tool (available at www.epa.gov/npdes/urbanbmptool) which presents BMP performance data from more than 220 scientific studies. This tool contains many of the studies collected by the International Stormwater BMP Database (www.bmpdatabase.org) and allows a user to search BMP performance data by their pollutant of interest, by the type of BMP they may want to install, or by the volume of stormwater reduction they would like to achieve.
The Urban BMP Performance Tool results are displayed showing both the influent and effluent concentrations of each BMP, with the effluent concentrations sorted from low to high. Volume reduction information is also displayed, where available.
There are many ways the Urban BMP Performance Tool can be used. However, two common approaches include: (1) finding the best BMP for controlling a specific pollutant, or (2) determining how a specific BMP performs across a range of pollutants and parameters.
Users who are concerned about a specific pollutant, for example, those who are in an impaired watershed with a TMDL, should select “search studies by the pollutants that were measured.” This allows users to identify a specific pollutant or pollutant group and see the most effective BMPs. Users who are interested in how effective a particular BMP is in controlling different pollutants should select “search studies by the BMPs examined.” Users then select the BMP and can further narrow their search by selecting an appropriate pollutant group.
This tool provides valuable information to help users select a better BMP for their site. As discussed above, however, there are many factors that go into proper BMP selection; therefore users should not just select the first BMP on the list. USEPA will continue to update the Urban BMP Performance Tool and add additional studies and BMPs as the data become available.
SUMMARY
Choosing effective BMPs is a significant challenge for all of us in the stormwater community. As discussed in this article there are still many unknowns, and the many considerations that we need to balance can make the task challenging. Fortunately, tools, backed by reliable scientific studies, are emerging that will help us improve the process of choosing better BMPs.
Author Link:
John Kosco, P.E.
Tetra Tech, Inc
10306 Eaton Place, Suite 340
Fairfax, VA 22046
(703) 385-6000
john.kosco@tetratech.com
singelis.nikos@epa.gov
John Kosco has over 15 years of experience working on stormwater programs, including stormwater program development, implementation, and compliance. He currently manages Tt’s stormwater support to USEPA and has extensive experience with the Phase I and Phase II stormwater regulations. John holds a B.S. degree in agricultural engineering from the Pennsylvania State University and an M.S. degree in Civil/Water Resources Engineering from George Washington University.
Editor’s Note: Additional articles may be found in AWRA’s bi-monthly magazine IMPACT.
