Water Forward 2024 Plan Report - Austin's 100 Year Plan

City of Austin | December 6th, 2024

Water Forward 2024 is Austin’s 100-year integrated water resource plan. The purpose of Water Forward is to develop and implement diverse and environmentally conscious w

Water Forward 2024 is Austin’s 100-year integrated water resource plan. The purpose of Water Forward is to develop and implement diverse and environmentally conscious water management strategies to adapt to growth, drought, and climate change and ensure a sustainable, resilient, equitable, and affordable water future for our community for the next 100 years. Austin Water has developed this plan to address near- and long-term water needs through a collaborative process in alignment with guiding principles crafted to reflect the Austin community’s values. 

Water requirement of Urban Green Infrastructure under climate change

Science of the Total Environment (Elsevier) | June 16th, 2023

The increased uncertainty of rainfall and high urban temperatures resulting from climate change present challenges for water management in Urban Green Infrastructure (UGI

The increased uncertainty of rainfall and high urban temperatures resulting from climate change present challenges for water management in Urban Green Infrastructure (UGI). UGI is an important component of cities, and it plays a crucial role in addressing various environmental issues (e.g., floods, pollutants, heat islands, etc.). Effective water management of UGI is essential to ensure its environmental and ecological benefits in the face of climate change. However, previous studies have not adequately investigated water management strategies for urban-scale GI under climate change scenarios. This study aims to estimate the current and future water requirement and effective rainfall (rainwater stored in the soil and plant roots available for plant evaporation) to determine the irrigation requirement of UGI during periods of rainfall deficit under current and future climate conditions. The results indicate that the water requirement for UGI will continue to increase under both RCP4.5 and RCP8.5 climate scenarios, with a higher increase projected under RCP8.5. For instance, the average water requirement for UGI is currently 731.29 mm, and it is projected to increase to 756.45 mm (RCP4.5) and 816.47 mm (RCP8.5) in summer during the period of 2081–2100, assuming low managed water stress condition. In addition, the water requirement of UGI in Seoul is the highest in June (approximately 125–137 mm) and the lowest in December or January (about 5–7 mm). While irrigation is unnecessary in July and August due to sufficient rainfall, other months in Seoul require irrigation when rainfall is insufficient. For example, continuous insufficient rainfall from May to June 2100 and April to June 2081 would need >110 mm (RCP4.5) of irrigation requirement even under high managed water stress condition. The findings of this study provide a theoretical foundation for water management strategies in current and future UGI settings.

Water Resource Modeling of the Colorado River: Present and Future Strategies

Utah State University | August 21st, 2019

The CRSS is imprecisely configured to address water supply and environmental management issues within many large tributaries of the headwater branches, including the Colo

The CRSS is imprecisely configured to address water supply and environmental management issues within many large tributaries of the headwater branches, including the Colorado River upstream from Glenwood Springs, the Yampa River upstream from Maybell, the Little Snake River upstream from Lily, the Dolores River, the Duchesne River watershed, the White River upstream from Watson, the Animas River, the Little Colorado River watershed, the Virgin River watershed, and other tributaries in the Lower Basin. Today, river management programs, endangered fish recovery programs, and some Native American tribes are focusing on these tributaries. It is important for stakeholders to understand that the CRSS is most appropriate for addressing basin-wide issues but is not designed to address issues within these tributaries. Expanding the spatial resolution of the CRSS to do so will require significant effort.

Water Resources Systems Planning and Management: An Introduction to Methods, Models and Applications

United Nations (UN) | January 1st, 2017

Throughout history, much of the world has witnessed ever-greater demands for reliable, high-quality and inexpensive water supplies for domestic consumption, agriculture,

Throughout history, much of the world has witnessed ever-greater demands for reliable, high-quality and inexpensive water supplies for domestic consumption, agriculture, and industry. In recent decades there have also been increasing demands for hydrological regimes that support healthy and diverse ecosystems, provide for water-based recreational activities, reduce if not prevent floods and droughts, and in some cases, provide for the production of hydropower and ensure water levels adequate for ship navigation. Water managers are challenged to meet these multiple and often conflicting demands. At the same time, public stakeholder interest groups have shown an increasing desire to take part in the water resources development and management decision-making process. Added to all these management challenges are the uncertainties of natural water supplies and demands due to changes in our climate, changes in people's standards of living, changes in watershed land uses and changes in technology. How can managers develop, or redevelop and restore, and then manage water resources systems - systems ranging from small watersheds to those encompassing large river basins and coastal zones - in a way that meets society's changing objectives and goals? In other words, how can water resources systems become more integrated and sustainable?

Water Supply Damage, Recovery, and Lifeline Interaction in an Earthquake Sequence

American Society of Civil Engineers (ASCE) | September 7th, 2017

Earthquake damage to water supply systems profoundly affects society, potentially costing the economy tens of billions of dollars. Water agencies for 22% of the U.S. popu

Earthquake damage to water supply systems profoundly affects society, potentially costing the economy tens of billions of dollars. Water agencies for 22% of the U.S. population face high seismic risks. Computer models can help operators manage that risk. In recent research, the University of Colorado (CU) developed a stochastic model of water-supply pipeline damage and restoration. It offers some new capabilities: time-varying repair resources, multiple earthquake perils, lifeline interaction, avoiding hydraulic analysis, and no black-box software. CU exercised the model for the East Bay Municipal Utility District (EBMUD) and the San Jose Water Company, considering a hypothetical large Hayward Fault earthquake. EBMUD staff peer reviewed the methodology and results and find them credible and consistent with past earthquakes. EBMUD is using the results as part of its resilience program. Possible uses include prioritizing additional hardening or redundancy, identifying repair priorities, estimating resource needs, and informing earthquake exercises.

Water Temperature Modeling Platform Mid-Term Review

Delta Stewardship Council (Delta Council) | October 21st, 2021

WESim – The Water-Energy Simulator – Helps Water and Energy Managers Plan for Change

Pacific Institute | July 5th, 2012

The Water–Energy Simulator (WESim) is an easy-to-use analytical tool that can be used to evaluate the energy and greenhouse gas implications of water management decisio

The Water–Energy Simulator (WESim) is an easy-to-use analytical tool that can be used to evaluate the energy and greenhouse gas implications of water management decisions. The Excel-based model allows the user to explore a range of possible scenarios, such as increased demand for water resources, the development of alternative water and energy sources, and needed water treatment improvements resulting from emerging contaminants and stricter water-quality guidelines. WESim can be applied by individual water and energy utilities, groups of utilities, and policymakers and decision makers. A WESim User Manual and report, Implications of Future Water Supply Sources for Energy Demands, are provided, as well. Water provision and use require energy in all phases, from source extraction to the discharge of wastewater. Multiple factors will influence the energy intensity of the water sector in the near future: climate change will affect water supply, quality, and demand, potentially creating a need for new energy-intensive supply and treatment options; population growth, water use patterns, technology, and price all will affect water demand; and emerging contaminants may require more energy-intensive treatment technologies. These trends highlight the need for a clear and consistent methodology for evaluating the energy and greenhouse gas implications of water management decisions. WESim addresses this need, as a tool that creates a common framework in which to explore alternative scenarios. The model is designed to allow you to input actual operating data on water and energy use, allowing for an analysis that better reflects operating conditions. To facilitate use of the model, defaults for the energy requirements of various components of the water and wastewater system are provided, as well. WESim was developed by The Pacific Institute and Dr. Bob Wilkinson, with support from the WateReuse Research Foundation, the California Energy Commission, and the Canadian Mortgage and Housing Corporation.

West-Wide Climate Risk Assessments: Irrigation Demand and Reservoir Evaporation Projections

U.S. Bureau of Reclamation (USBR) | February 5th, 2015

Section 9503 of the SECURE Water Act, Subtitle F of Title IX of P.L. 111-11 (2009) (SECURE Water Act), authorizes the Bureau of Reclamation (Reclamation) to evaluate the

Section 9503 of the SECURE Water Act, Subtitle F of Title IX of P.L. 111-11 (2009) (SECURE Water Act), authorizes the Bureau of Reclamation (Reclamation) to evaluate the risks and impacts of climate change in each of the eight major Reclamation river basins identified in the Act, and to work with stakeholders to identify climate adaptation strategies. Reclamation implements Section 9503 of the SWA through the Department of Interior’s WaterSMART Program1, which is working to achieve a sustainable water strategy to meet the Nation’s water needs now and for the future. Through Basin Studies, part of WaterSMART, Reclamation works with State and local partners to evaluate the ability to meet future water demands within a river basin and to identify adaptation and mitigation strategies of the potential impacts of climate change. Through another activity, West-Wide Climate Risk Assessments (WWCRA), Reclamation is working to provide projections of future changes in water supplies, water demands, and river system operations that could result from changes in climate. As part of WWCRA, Reclamation has conducted an analysis of the potential changes in crop irrigation demand in eight major river basins in the West and projections of evaporation for 12 reservoirs within those river basins when considering observed and projected impacts of climate change. This report contains the results of that analysis. The findings presented in this report are intended to be used for future basin-specific WWCRA impact assessments and Basin Studies conducted under WaterSMART if the teams conducting those studies elect to do so. This technical assessment report provides: (1) an analysis of changes in irrigation demand, and (2) an analysis of changes in evaporation for selected reservoirs across the major Reclamation river basins with respect to presently observed and projected future impacts of global climate change. The analysis involved developing irrigation demand and reservoir evaporation projections associated with World Climate Research Programme Coupled Model Intercomparison Project3 (WCRP CMIP3) climate projections that have been bias-corrected and spatially downscaled (BCSD) and served at the following Web site: http://gdo-dcp.ucllnl.org/downscaled_cmip_projections/dcpInterface.html. For the purposes of this study, CMIP3 climate projections were used because they represented the best available collection of climate projections at the onset of this effort (summer 2011 which was begun prior to the release of CMIP5). Although the CMIP3 and CMIP5 projections are considered equally likely potential climate futures at this time, there is significant variability in the two sets of projections. This is especially true with regard to precipitation projections, and it is significant to note the potential impact of this variability on future irrigation demand and net evaporation estimates. Changes to irrigation demand (model, described below) were analyzed for five climate change scenarios (warm-dry, warm-wet, hot-dry, hot-wet, and central tendency – ensemble median) that were informed by 112 BCSD-CMIP3 projections at three future periods: 2020s (years 2010-2039), 2050s (years 2040–2069), and 2080s (2070-2099) with 1950–1999 as the baseline period. The reservoir evaporation modeling (described below) was performed as transient simulations using the individual 112 BCSD-CMIP3 projections. Both the irrigation demands modeling and the reservoir evaporation modeling used observed data from weather stations representative of irrigated land areas and reservoir sites in a secondary bias correction step to account for local scale climate conditions in the climate change scenarios. Although it would be ideal to calculate future irrigation demands for all 112 projections using the transient method as was done for the future reservoir evaporation estimates, such calculations were not feasible given the multiple crops and numerous locations modeled.

Why Seasonal Prediction of California Winter Precipitation is Challenging

American Meteorological Society (AMS) | December 7th, 2022

Despite an urgent demand for reliable seasonal prediction of precipitation in California (CA) due to the recent recurrent and severe drought conditions, our predictive sk

Despite an urgent demand for reliable seasonal prediction of precipitation in California (CA) due to the recent recurrent and severe drought conditions, our predictive skill for CA winter precipitation remains limited. October hindcasts by the coupled dynamical models typically show a correlation skill of about 0.3 for CA winter (November–March) precipitation. In this study, an attempt is made to understand the underlying processes that limit seasonal prediction skill for CA winter precipitation. It is found that only about 25% of interannual variability of CA winter precipitation can be attributed to influences by El Niño–Southern Oscillation (ENSO). Instead, the year-to-year CA winter precipitation variability is primarily due to circulation anomalies independent from ENSO, featuring a circulation center over the west coast United States as a portion of a short Rossby wave train pattern over the North Pacific. Analyses suggest that dynamical models show nearly no skill in predicting these ENSO-independent circulation anomalies, thus leading to limited predictive skill for CA winter precipitation. Low predictability of these ENSO-independent circulation anomalies is further demonstrated by a large ensemble of atmospheric-only climate model simulations. While low predictability of the ENSO-independent circulation anomalies could be due to chaotic internal atmospheric processes over the mid- to high latitudes, possible underexploited predictability sources for CA precipitation in models are also discussed. This study pinpoints an urgent need for improved understanding of the formation mechanisms of ENSO-independent circulation anomalies over the U.S. West Coast for a breakthrough in seasonal prediction of CA winter precipitation.

Wind Over San Francisco Bay and the Sacramento-San Joaquin River Delta: Forcing for Hydrodynamic Models.

San Francisco Estuary Institute (SFEI) | March 25th, 2019

The Ludwig wind model (Ludwig et al., 1991; Ludwig and Sinton, 2000) has been used to generate spaio-temporally varying wind inputs for hydrodynamic models of the San Fr

The Ludwig wind model (Ludwig et al., 1991; Ludwig and Sinton, 2000) has been used to generate spaio-temporally varying wind inputs for hydrodynamic models of the San Francisco Bay and Sacramento-San Joaquin River Delta (SFB-Delta) in recent projects at Deltares (Achete et al., 2015), at the United States Geological Survey (USGS; Martyr-Koller et al., 2017), and at San Francisco Esturary Institute (SFEI; Nuss et al., 2018). These projects all utilize hydrodynamic models in the Deltares suite of software known as DFlow (e.g., Deltares, 2019), and the wind inputs to DFlow are specied hourly on a 1.5 km x 1.5 km grid.