Hydrologics Presents

Risk Management for Municipal Water Supply

Understanding the Role of Risk Management and the Limitations of Safe Yield in the Planning and Operations of Municipal Water Systems

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What’s New

Dynamic Reservoir Operations:  Managing for Climate Variability and Change

The Water Research Foundation has released two reports as part of a collaborative research project lead by HydroLogics, Inc. The first identified how reservoir operations can be adjusted to adapt to hydrologic changes associated with climate change and the uncertainties associated with climate variability based on the literature and six case studies.  Results from one of these case studies, the Washington Metropolitan Area, were presented at the 2014 AWRA Annual Conference. The second report pulls out the chapter on the process of developing effective reservoir operations.

2014 Annual Colorado Association of Stormwater and Floodplain Managers Conference

Casey Caldwell will present "After the Flood:  Using Collaborative Tools to Inform Future Preparedness" on Wednesday, October 1st at 2 pm during the Emergency Preparedness track. The focus of the presentation will be HydroLogics' work on a collaborative approach to flood mitigation for the Bow River basin in Alberta Canada.

First of Its Kind Modeling System for Reservoir Modeling

HydroLogics has been an integral member of the team that developed the City of New York's Operations Support Tool (OST), a system of databases and computer software that incorporates real-time data, advanced forecasts, and computer simulation to guide both daily and long-term reservoir operations decisions.  The OST is the product of many years of collaboration on the planning of better operations for the NYC water supply system and the Delaware River Basin.  HydroLogics was involved in the planning and implementation of the real-time data collection system, the forecasting methodologies, and the water quality and quantity simulation tools.  Our most important role was in the redesign of the OASIS software so that it can be used as the core component of the OST.  The overhauled OASIS GUI is used to automatically execute any of a number of different types of forecasts.  It also allows multiple users to collaborate on the creation of simulation scenarios, and to compare the different assumptions of multiple simulated scenarios in a side-by-side manner.  The OST is now in daily use by staff at the NYC Department of Environmental Protection (DEP).  Read more about the OST on the DEP news release.

Water Transfer Agreements

Impact of Contract Structure and Risk Aversion on Interutility Water Transfer Agreements,” written by HydroLogics' Casey Caldwell, and and his graduate school advisor Greg Characklis was recently published in the Journal of Water Resources Planning and Management, January 2014, Vol. 140, No. 1, pp. 100-111.

NY Pioneers System to Protect Drinking Water from Adverse Weather Events

Groundbreaking work by HydroLogics and others on forecast-based real-time water management decision support for the New York City drinking water system is featured in the article "Forecasts Turn Tide on Silt" in the August 20, 2013 issue of Nature (Vol. 500, Iss 7463).

Water Disputes Negotiations

Computer-Aided Negotiations of Water Disputes:  An Interdisciplinary Role-Playing Course written by Drs. Megan Rivera, Daniel Sheer et.al. appeared in the Journal of American Water Resources June 2013 issue as part of its featured collection on collaborative modeling for decision support as a tool to implement IWRM.  Volume 49, Issue 3, p. 700-714. 

New Strategy for Operating the Bow River Basin

"Developing a New Operations Plan for the Bow River Basin Using Collaborative Modeling for Decision Support" written by A. Michael Sheer, Daniel Sheer, Samuel Lebherz et. al. was also published in the  Journal of the American Water Resources Association focused on collaborative modeling for decision support as a tool to implement IWRM, June 2013, Volume 49, Issue 3, p. 654-668. 

ASCE book features OASIS software in evaluating complex environmental and water resources systems

Computer Aided Negotiation and River Basin Management in the Delaware by Megan Wiley Rivera and Daniel Sheer, Chapter 7 p 66 in Water Resources System Analysis Through Case Studies;   Data and Models For Decision Making, prepared by Task Committee on Environmental and Water Resources Systems Education, Edited By David W. Watkins Jr., Ph.D. Sponsored By Environmental and Water Resources Institute American Society of Civil Engineers. 

2013 AWRA Environmental Flows Conference

Megan Wiley Rivera, Steve Nebiker, and James Limbrunner are participating in the 2013 Environmental Flows Specialty Conference in Hartford, Connecticut June 24 and 25.

Dr. Rivera will present Monday at 10:30 am in Session 2:  Application and Assessment of E-flows 1: Dealing with Uncertainty in Managing for Instream Flows (co-author:  D.P. Sheer)

Mr. Nebiker will present Tuesday at 8:50 am in Session 9:  Application and Assessment of E-flows 2:  Balancing Competing Uses of Water:  The Smith Mountain-Leesville Low Flow Protocol (co -author:  T. Rogers)

Look for us there or at the HydroLogics booth!  More information can be obtained here

Water Use Forecasting

HydroLogics will be presenting on risk management at the ASCE-NC Spring Technical Seminar in Raleigh on April 26, 2013.  The focus of the talk will be on the development of effective triggers to enable water utilities to better manage risks during drought.  Well-crafted drought plans, in turn, can inform the planning process, allowing utilities to strike a better balance between system reliability and cost.

Regional Drought Management Plan

Casey Caldwell presented "Development of a Regional Drought Management Plan Using Collaborative Modeling" at the American Water Works Association's Sustainable Water Management Conference on April 8, 2013 in Nashville, TN. The presentation focused on HydroLogics' recent work on the Duck River in Tennessee.

New Release Protocol

The Appomattox River Water Authority in Petersburg, Virginia, has contracted with the Raleigh office of HydroLogics to evaluate the impacts of a proposed new release protocol from Lake Chesdin.  Lake Chesdin is ARWA’s raw water source and a heavily-used recreational facility.  The system has been severely stressed during the several droughts of the past decade, necessitating numerous permit variances from the Virginia Department of Environmental Quality.  With the new release protocol, DEQ is attempting to rebalance the multiple uses of the reservoir, including aquatic habitat downstream and the opportunity for the out-migration of anadromous fish in the fall.  HydroLogics developed performance metrics for the various uses and then used an OASIS application to develop drought triggers and assess system performance for the proposed and alternative release protocols.  HydroLogics is now assisting ARWA and DEQ as they attempt further refinements to improve performance.

Preserving Raleigh's Water Supply Reliability

The Raleigh City Council recently approved a seasonally-based, three-stage drought plan developed by HydroLogics in consultation with Hazen & Sawyer.  The plan, which preserves water supply reliability while minimizing the frequency of invoking water use restrictions, was based on  simulations using the NC Division of Water Resources 'Neuse River Basin Model, an application of OASIS also developed by HydroLogics.

Water in a World of 7 Billion

A. Michael Sheer is an invited speaker at the Water in a World of 7 Billion Conference in Calgary, on May 10, 2012.  The discussion will focus on the Bow River Operations Model.

2012 American Water Works Annual Meeting

Dan Sheer and Megan Wiley Rivera will be at the American Water Works Association Annual Meeting ACE 2012 in Dallas, TX from June 11 and 12th.  They are presenting at 9:30 AM (session TUE13) on Dynamic Reservoir Operations (DRO) for Water Supply Planning, sharing results to date from a Water Research Foundation project on DRO as a response to climate change.

2012 Institute for Environmental Conflict Resolution Conference

Megan Wiley Rivera will be at the U.S. Institute for Environmental Conflict Resolution’s seventh national conference, ECR2012: "Working Across Boundaries," May 22-24, 2012, at the JW Marriott Starr Pass in Tucson, Arizona.  Find her at the HydroLogics’ display at the Technology Fair on Wednesday night.

2012 AGU Science Policy Conference

Michael Sheer will present a poster entitiled "Informing Policy Decisions through Collaborative Modeling in the Bow River Basin" at the American Geophysical Union Science Policy Conference, May 1 & 2, 2012 in Washington D.C.   QRCode

Dynamic Reservoir Operations for Water Supply Planning

Megan Rivera will present her paper "Dynamic Reservoir Operations for Water Supply Planning" at the American Water Works Association's annual meeting June 10-14, 2012 in Dallas Texas.

Statewide OASIS License

Tennessee Licenses OASIS for Statewide Use. The State of Tennessee has joined Kansas and North Carolina in licensing OASIS for use throughout the State. The software will be made available to government, consultants, academia, and others via a server housed at Tennessee Technological University in Cookeville. Tennessee Tech is the State's only technological university and provides leadership and programs in engineering, the sciences, and related areas. The Center for the Management, Utilization, and Protection of Water Resources will maintain the software, develop applications and training programs, and instruct graduate students in the use of OASIS. Over time, these graduate students will form a cadre of trained users to the profession.

Converging Waters: Integrating Collaborative Modeling with Participatory Processes to Make Water Resources Decisions

HydroLogics’ work is featured in the U.S. Army Corps of Engineers’ new book Converging Waters: Integrating Collaborative Modeling with Participatory Processes to Make Water Resources Decisions.  Brian McCrodden authored Chapter 5: Reflections of Computer–Aided Dispute Resolution (CADRe) on the Roanoke and Megan Wiley Rivera authored Chapter 13: Training and Education.  Other examples of HydroLogics’ Computer-Aided Negations processes are included throughout the book.

AWRA 2011 Spring Specialty Conference

HydroLogics is a sponsor for the "Managing Climate Change Impacts on Water Resources:  Adaptation Issues, Options & Strategies" conference in Baltimore Maryland April 18-20.  Daniel Sheer is a panelist on What Should Water Utilities Do Now to Prepare for Possible Climate Change Impacts on April 20th. 

Tufts University Water: Systems, Science and Society Symposium

Daniel Sheer will be a keynote speaker at the "Water in 2050: The Infrastructure to Get There" on April 1, 2011.

AWWA - Water, Energy, and Sustainability Symposium

Daniel Sheer and Megan Rivera are featured on panels at this Water Resources Symposium March 14-16 in Orlando, Florida.  The sessions are "Climate Change and Water Resource Operations" and "Innovative Methods to Plan and Manage Water Supplies".

Nova Scotia Canada

In February 2011, the Nova Scotia Utility and Review Board contracted with HydroLogics to provided integrated water resource management for water and sewer. 


UMBC Course

Computer Aided Negotiations of Natural Resource Disputes, a course developed jointly by University of Maryland Baltimore County (UMBC) and HydroLogics with NSF support, will be offered this fall at UMBC.  We will also be piloting a condensed version of the course at University of Texas at Austin this semester.  Students role-play a CAN process in the Delaware River Basin using the basin’s water management OASIS model.  More information and course materials can be found here.

Some suggested links:

Computer Aided Negotiations of Natural Resource Disputes, a course developed jointly by University of Maryland Baltimore County (UMBC) and HydroLogics with NSF support, will be offered this fall at UMBC.  We will also be piloting a condensed version of the course at University of Texas at Austin this semester.  Students role-play a CAN process in the Delaware River Basin using the basin’s water management OASIS model.  More information and course materials can be found here.

AWWA Article in OPFLOW

"Drought Management:  Probability-Based Operating Rules Improve Water Supply Management", by Brian McCrodden, Steven Nebiker, and Leslie Carreiro, OPFLOW by the American Water Works Association, June 2010, Vol. 36, No. 6, pp 22-24.

North Carolina Tar & Broad River Basins

May 2010. The North Carolina Department of Environment and Natural Resources has contracted with HydroLogics’ Raleigh office to build OASIS applications of the Tar and Broad River basins. The models will be used by the Division of Water Resources to develop basinwide water supply plans and to evaluate applications for interbasin transfer permits. The applications will be available to municipalities and the private sector via DWR’s server. Plans are to develop OASIS applications for each of the State’ 17 major river basins. This brings to seven the number developed thus far by HydroLogics.


"Dysfunctional Water Management:  Causes and Solutions," Journal of Water Resources Planning and Management, January/February 2010, Vol. 136, No. 1, p. 1-4.

College Course

Megan Wiley Rivera will be hosting two conference call/webviewer meetings to talk about the course Computer Aided Negotiations of Water Resources Disputes for anyone interested in teaching the course, using the materials, or learning more: Tuesday, November 24, 2009 1 PM EST and Wednesday, December 2, 2009 4 PM EST.  Please see http://www.hydrologics.net/CAN_Course/ for more information.

West Palm Beach

In November 2009, HydroLogics completed a surface water model for the City of West Palm Beach, Florida that will be used by City personnel to optimize its water resources, particularly during drought, over short-term (one week) and medium-term (up to one year) horizons.  The tool can also be used for long-range planning and performing analyses designed to adapt operating policies to changing conditions.

HydroLogics Implements Genetic Algorithm Search with OASIS

HydroLogics has successfully implemented Genetic Algorithm wrappers for the OASIS model. The GA wrapper searches for improved parameters and forms of operating rules for multi-objective management of water resource systems.  It works by combining and recombining parameters and rule forms from the best of previously evaluated alternatives in a way that is similar to selective breeding. The wrapper uses an Excel interface to structure the search and can use either the Frontline solver for Excel or HydroLogics internally developed parallel processing GA.  The GA wrapper has been used to substantially improve simulated operating policies for the Apalachicola Chattahoochee Flint Basin in Georgia, Alabama and Florida and for Lakes Rotorua and Rotoiti in New Zealand.

South Florida

The Kissimmee Basin Modeling and Operations Study (KBMOS) has been undertaken by the South Florida Water Management District (SFWMD).  An OASIS model of the basin (OKISS) is central to this effort.  OKISS has been used in four Computer-Aided Negotiation (CAN) sessions in which stakeholders have tested, refined, and combined their ideas for operating policies.  HydroLogics has also created a “heuristic” spreadsheet wrapper that uses a gradient search technique to fine-tune parameters of the operating policies to improve biological performance while meeting flood control and other constraints.

AWWA Journal article

"Science Based Collaboration:  Finding Better Ways to Operate the Conowingo Pond," written by Dr. Sheer, appeared in the AWWA Journal, June 2009 on page 20. 

National Hydropower Association Conference

Brian McCrodden will participate in a panel discussion on "Stakeholder Collaboration:  Strengthening the Partnership" at the National Hydropower Association Annual Conference in Washington, D.C. May 11-13, 2009

U.S. Institute for Environmental Conflict Resolution

Daniel Sheer is a presenter at the U.S. Institute for Environmental Conflict Resolution National Strategic Planning Session May 6-8, 2009 in Tucson, AZ.  The topic is "HydroLogics Computer Aided Negotiation and Operations Exercises Using OASIS."

Safe Yield Analyses

The Raleigh office has been retained by McGill Associates to conduct safe yield analyses for the City of Hendersonville and the Town of Mars Hill, North Carolina.

Progress Energy

The Raleigh, NC, office has been selected by Progress Energy to provide permitting support for the expansion of its Shearon Harris nuclear plant southwest of Raleigh. Progress Energy is proposing to withdraw water from the nearby Cape Fear River to provide additional cooling water for the expanded plant.  HydroLogics will use the Cape Fear River Basin Hydrologic Model previously developed for the NC Department of Environment and Natural Resources to evaluate operating scenarios that will provide the necessary cooling water while protecting the aquatic resources of the Cape Fear River.

Computer-Aided Negotiation - Canada

The week of September 22, 2008, HydroLogics is in Lethbridge, Alberta, running a model-aided negotiation meeting with the stakeholders of the South Saskatchewan River Basin.  This is the final task in our South Saskatchewan project, the main task of which was to build an OASIS model of the system.

OASIS @ University of Maryland

The NSF-supported course Computer Aided Negotiation of Water Resources Disputes has begun!  Fourteen University of Maryland Baltimore County students from various disciplines (including Political Science, Environmental Studies, Economics, History, and Chemical Engineering) are role-playing stakeholders in the Delaware River Basin with the goal of developing operations that better serve all parties' interests.  UMBC and HydroLogics partnered on the grant proposal, and Dr. Megan Rivera of HydroLogics is teaching the course.  Information about the course can be found by searching for "GES200H" at this site. 

New York City - Drought Risk Analysis

The New York City Bureau of Water Supply (BWS) has contracted with HydroLogics to perform an analysis of the drought risk associated with operating its reservoirs at a lower elevation to provide additional flood control benefits for those downstream.  BWS has long operated its water supply reservoirs in the Catskill Mountains so as to be full on June 1 of each year, meaning that the reservoirs are often full or near-full during the spring when flows are usually at their highest.  Providing additional flood control would require that the reservoirs be maintained at a lower level throughout the spring, leading to the possibility that the reservoirs might not be full on June 1. HydroLogics will perform the analysis with the existing OASIS model of the New York City water supply system.  The OASIS model will be used in “position analysis” mode to determine the probabilities of events such as: reservoirs going into drought “watch,” drought “warning,” and “drought” levels and the resulting shortages, if any, in NYC water supply.


Numerous clients have asked about performing IHA (Indicators of Hydrologic Alteration) analyses on OASIS output.  We are in the process of integrating the two software packages so that OASIS results are automatically loaded into IHA when the user pushes a button in the OASIS GUI. The linked programs will be available for demonstration at the FLOW 2008 conference.

Saugatuck River

January, 2008. The Raleigh Office was awarded a contract jointly funded by Aquarion Water Company and The Nature Conservancy to develop an OASIS model of Aquarion's Bridgeport, Connecticut, water system. Aquarion is interested in system reliability, and TNC is interested in environmental flows, particularly in the Saugatuck River. The model will be used to investigate operating strategies that might improve environmental flows without jeopardizing water supply reliability. The project is scheduled for completion in December, 2008.

State of North Carolina

January, 2008. The North Carolina Department of Environment and Natural Resources (DENR) has purchased a license to use OASIS throughout the state. DENR intends to develop an OASIS application of each of the ten major river basins in the state and make them available to local governments and consultants for their use in water supply planning and permitting activities.

DENR has also contracted with HydroLogics to develop an OASIS application for the Neuse River basin, which provides water supply for the cities of Raleigh and Durham. It is anticipated that the model will be useful as the Research Triangle region develops more sophisticated drought management plans and for addressing water quality issues downstream in the coastal plain.

Risk Management For Municipal Water Supply

HydroLogics is pleased to offer a presentation entitled “Risk Management for Municipal Water Supply”, featuring a discussion about the traditional safe yield approach, its limitations, and the advantages of risk management in the context of drought management and capacity planning.

This Macromedia Flash presentation contains an overview of our company's mission, experience, municipal services and products, and OASIS software. Testimonials from clients using our risk management approach are also included.  This presentation educates water system managers, planners, regulators, environmental groups, and other stakeholders about more sustainable water management strategies.


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