Howard David Passell

System dynamics modeling for community-based water planning: Application to the Middle Rio Grande

Abstract.The watersheds in which we live are comprised of a complex set of physical and social systems that interact over a range of spatial and temporal scales. These systems are continually evolving in response to changing climatic patterns, land use practices and the increasing intervention of humans. Management of these watersheds benefits from the development and application of models that offer a comprehensive and integrated view of these complex systems and the demands placed upon them. The utility of these models is greatly enhanced if they are developed in a participatory process that incorporates the views and knowledge of relevant stakeholders. System dynamics provides a unique mathematical framework for integrating the physical and social processes important to watershed management, and for providing an interactive interface for engaging the public. We have employed system dynamics modeling to assist in community-based water planning for a three-county region in north-central New Mexico. The planning region is centered on a ~165-km reach of the Rio Grande that includes the greater Albuquerque metropolitan area. The challenge, which is common to other arid/semi-arid environments, is to balance a highly variable water supply among the demands posed by urban development, irrigated agriculture, river/reservoir evaporation and riparian/in-stream uses. A description of the model and the planning process are given along with results and perspectives drawn from both.

Mapping water availability, projected use and cost in the western United States

New demands for water can be satisfied through a variety of source options. In some basins surface and/or groundwater may be available through permitting with the state water management agency (termed unappropriated water), alternatively water might be purchased and transferred out of its current use to another (termed appropriated water), or non-traditional water sources can be captured and treated (e.g., wastewater). The relative availability and cost of each source are key factors in the development decision. Unfortunately, these measures are location dependent with no consistent or comparable set of data available for evaluating competing water sources. With the help of western water managers, water availability was mapped for over 1200 watersheds throughout the western US. Five water sources were individually examined, including unappropriated surface water, unappropriated groundwater, appropriated water, municipal wastewater and brackish groundwater. Also mapped was projected change in consumptive water use from 2010 to 2030. Associated costs to acquire, convey and treat the water, as necessary, for each of the five sources were estimated. These metrics were developed to support regional water planning and policy analysis with initial application to electric transmission planning in the western US.

AMMONIA MODELING FOR ASSESSING POTENTIAL TOXICITY TO FISH SPECIES IN THE RIO GRANDE, 1989–2002

Increasing volumes of treated and untreated human sewage discharged into rivers around the world are likely to be leading to high aquatic concentrations of toxic, unionized ammonia (NH3), with negative impacts on species and ecosystems. Tools and approaches are needed for assessing the dynamics of NH3. This paper describes a modeling approach for first-order assessment of potential NH3 toxicity in urban rivers. In this study daily dissolved NH3 concentrations in the Rio Grande of central New Mexico, USA, at the city of Albuquerques treated sewage outfall were modeled for 1989-2002. Data for ammonium (NH4+) concentrations in the sewage and data for discharge, temperature, and pH for both sewage effluent and the river were used. We used State of New Mexico acute and chronic NH3- N concentration values (0.30 and 0.05 mg/L NH3-N, respectively) and other reported standards as benchmarks for determining NH3 toxicity in the river and for assessing potential impact on population dynamics for fish species. A critical species of concern is the Rio Grande silvery minnow (Hybognathus amarus), an endangered species in the river near Albuquerque. Results show that NH3 concentrations matched or exceeded acute levels 13%, 3%, and 4% of the time in 1989, 1991, and 1992, respectively. Modeled NH3 concentrations matched or exceeded chronic values 97%, 74%, 78%, and 11% of the time in 1989, 1991, 1992, and 1997, respectively. Exceedences ranged from 0% to 1% in later years after enhancements to the wastewater treatment plant. Modeled NH3 concentrations may differ from actual concentrations because of NH3 and NH4+ loss terms and additive terms such as mixing processes, volatilization, nitrification, sorbtion, and NH4+ uptake. We conclude that NH3 toxicity must be considered seriously for its potential ecological impacts on the Rio Grande and as a mechanism contributing to the decline of the Rio Grande fish community in general and the Rio Grande silvery minnow specifically. Conclusions drawn for the Rio Grande suggest that NH3 concentrations may be high in rivers around the world where alkaline pH values are prevalent and sewage treatment capabilities are poorly developed or absent.

COMMENTARY: Cooperative Modeling Lessons for Environmental Management

Environmental practitioners may find cooperative modeling an effective tool to address complex environmental management needs. The method involves convening a multidisciplinary team to collaboratively construct a system dynamics model. Advances in computational tools have made this technique increasingly effective because the process and the product allow individuals to better understand the complexity inherent in the system being studied. The authors describe four cooperative modeling projects and document some of the “lessons learned” from these experiences. Two of these projects were largely academic and team members were all professionals who agreed to work together to build a model. The other two teams were convened to contribute to water management processes. One of these emanated from a regional planning exercise and the team included professionals and volunteers from the public. The final project team presented includes professionals, members of the public, and government agency personnel. Like any multidisciplinary effort, the teams encountered communication challenges. The overarching lessons derived from these efforts are that teams can never pay too much attention to group dynamics and that the proximity to a “real” management decision does influence the cooperative modeling process. Recommendations to others embarking on a cooperative modeling effort include reviewing the literature regarding previous projects; establishing clear guidelines for team interaction early in the project; and remaining flexible, to allow the project to evolve.

A study of algal biomass potential in selected Canadian regions.

A dynamic assessment model has been developed for evaluating the potential algal biomass and extracted biocrude productivity and costs, using nutrient and water resources available from waste streams in four regions of Canada (western British Columbia, Alberta oil fields, southern Ontario, and Nova Scotia). The purpose of this model is to help identify optimal locations in Canada for algae cultivation and biofuel production. The model uses spatially referenced data across the four regions for nitrogen and phosphorous loads in municipal wastewaters, and CO{sub 2} in exhaust streams from a variety of large industrial sources. Other data inputs include land cover, and solar insolation. Model users can develop estimates of resource potential by manipulating model assumptions in a graphic user interface, and updated results are viewed in real time. Resource potential by location can be viewed in terms of biomass production potential, potential CO{sub 2} fixed, biocrude production potential, and area required. The cost of producing algal biomass can be estimated using an approximation of the distance to move CO{sub 2} and water to the desired land parcel and an estimation of capital and operating costs for a theoretical open pond facility. Preliminary results suggest that in most cases, the CO{sub 2} resource is plentiful compared to other necessary nutrients (especially nitrogen), and that siting and prospects for successful large-scale algae cultivation efforts in Canada will be driven by availability of those other nutrients and the efficiency with which they can be used and re-used. Cost curves based on optimal possible siting of an open pond system are shown. The cost of energy for maintaining optimal growth temperatures is not considered in this effort, and additional research in this area, which has not been well studied at these latitudes, will be important in refining the costs of algal biomass production. The model will be used by NRC-IMB Canada to identify promising locations for both demonstration and pilot-scale algal cultivation projects, including the production potential of using wastewater, and potential land use considerations.

Data collection for cooperative water resources modeling in the Lower Rio Grande Basin, Fort Quitman to the Gulf of Mexico.

Water resource scarcity around the world is driving the need for the development of simulation models that can assist in water resources management. Transboundary water resources are receiving special attention because of the potential for conflict over scarce shared water resources. The Rio Grande/Rio Bravo along the U.S./Mexican border is an example of a scarce, transboundary water resource over which conflict has already begun. The data collection and modeling effort described in this report aims at developing methods for international collaboration, data collection, data integration and modeling for simulating geographically large and diverse international watersheds, with a special focus on the Rio Grande/Rio Bravo. This report describes the basin, and the data collected. This data collection effort was spatially aggregated across five reaches consisting of Fort Quitman to Presidio, the Rio Conchos, Presidio to Amistad Dam, Amistad Dam to Falcon Dam, and Falcon Dam to the Gulf of Mexico. This report represents a nine-month effort made in FY04, during which time the model was not completed.

Integrating Monitoring and Decision Modeling within a Cooperative Framework: Promoting Transboundary Water Management and Avoiding Regional Conflict

Surface and groundwater resources do not recognize political boundaries. Where nature and boundary cross, tension over shared water resources can erupt. Such tension is exacerbated in regions where demand approaches or exceeds sustainable supplies of water. Establishing equitable management strategies can help prevent and resolve conflict over shared water resources. This paper describes a methodology for addressing transboundary water issues predicated on the integration of monitoring and modeling within a framework of cooperation. Cooperative monitoring begins with agreement by international scientists and/or policy makers on transboundary monitoring goals and strategies; it leads to the process of obtaining and sharing agreed-upon information among parties with the purpose of providing verifiable and secure data. Cooperative modeling is the process by which the parties jointly interpret the data, forecast future events and trends, and quantify cause and effect relationships. Together, cooperative monitoring and modeling allow for the development and assessment of alternative management and remediation strategies that could form the basis of regional watershed agreements or treaties. An example of how this multifaceted approach might be used to manage a shared water resource is presented for the Kura River basin in the Caucasus.

Viability report for the ByWater Lakes project.

This report presents the results from the hydrological, ecological, and renewable energy assessments conducted by Sandia National Laboratories at the ByWater Lakes site in Espanola, New Mexico for ByWater Recreation LLC and Avanyu Energy Services through the New Mexico small business assistance (NMSBA) program. Sandias role was to assess the viability and provide perspective for enhancing the site to take advantage of renewable energy resources, improve and sustain the natural systems, develop a profitable operation, and provide an asset for the local community. Integral to this work was the identification the pertinent data and data gaps as well as making general observations about the potential issues and concerns that may arise from further developing the site. This report is informational only with no consideration with regards to the business feasibility of the various options that ByWater and Avanyu may be pursuing.

Sun City progress report : policy effects on photovoltaic adoption for city planning.

This progress report documents the Sun City modeling approach, intended to be an analytic tool for city planners. It is midway in development and this report provides the design basis to provide the mathematics for policy considerations applied to PV market acceleration. It assesses the effects on market diffusion for nine commonly used policies: cash incentives, third party financing, group purchase programs, community solar projects, feed-in-tariffs, property assessed clean energy financing, low interest loans, property and sales tax incentives, and streamlined PV permitting processes. Generic forms of all of these policies are modeled in a system dynamics PowerSim Studio model using a concept called the photovoltaic favorability (PVF). PVF is equal to the difference between the ratio of conventional electricity costs to levelized electricity costs of a PV system and four barrier ratios. The barriers are present to model inhibiting influences on human decisions and financial limitations. They include down payment costs, month to month payment costs of financing, time to net profit, and time to lower payments. Each barrier term is divided by a tolerance term which represents the potential that consumers of the region can typically invest. PVF is quantified across a range of limited budget financing and cash incentives options which are then consumed from greatest PVF to least PVF. Finding the overall PVF requires iteration on a variation of the Bass diffusion model. This iterative scheme is tied in a feed-back loop to local and national PV learning curves which in turn quantify reductions in the cost of PV for future time steps based on user input learning rates. The modeling has been wrapped into a graphical user interface which will allow city planners to easily compare and demonstrate multiple scenarios. Data for the DOE sponsored Solar America Cities and for Albuquerque, New Mexico has been entered into the model in order to minimize data collection efforts by city planners.

Sustainability innovation foundry : leveraging research and development for a sustainable Sandia.

Sustainability is a critical national security issue for the U.S. and other nations. SNL is already a global leader sustainability science and technology, but we can do more. This report documents the basis for the Sustainability Innovation Foundry and the outcomes from a workshop held on September 10, 2012. The workshop‟s goal was to initiate trans-disciplinary discussions and collaboration toward realization of a Sustainability Innovation Foundry (SIF). The efforts of the SIF will support Sandia‟s national and international security missions related to sustainability and resilience revolving around energy use, water use, and materials, both on site at Sandia and externally. The SIF will leverage existing Sandia research and development (R&D) in sustainability science and technology (SS&T) to support new solutions to complex problems. The SIF will also build on existing Sandia initiatives to transform Sandia into a fully sustainable entity in terms of materials, energy, and water use. The SIF will demonstrate the efficacy of sustainability technology developed at Sandia through prototyping and test bed approaches and will provide a common platform for support of solutions to the complex problems surrounding sustainability. Leadership-level funding will be required, but initial prototype projects are already underway with funding from Facilities.