Colorado River water supply is predictable on multi-year timescales owing to long-term ocean memory

Nature Portfolio (Springer Nature) | October 9th, 2020

Skillful multi-year climate forecasts provide crucial information for decision-makers and resource managers to mitigate water scarcity, yet such forecasts remain challen

Skillful multi-year climate forecasts provide crucial information for decision-makers and resource managers to mitigate water scarcity, yet such forecasts remain challenging due to unpredictable weather noise and the lack of dynamical model capability. Here we demonstrate that the annual water supply of the Colorado River is predictable up to several years in advance by a drift-free decadal climate prediction system using a fully coupled climate model. Observational analyses and model experiments show that prolonged shortages of water supply in the Colorado River are significantly linked to sea surface temperature precursors including tropical Pacific cooling, North Pacific warming, and southern tropical Atlantic warming. In the Colorado River basin, the water deficits can reduce crop yield and increase wildfire potential. Thus, a multi-year prediction of severe water shortages in the Colorado River basin could be useful as an early indicator of subsequent agricultural loss and wildfire risk.

Community and Grower Engagement in Multibenefit Land Repurposing

Environmental Defense Fund (EDF) | June 10th, 2022

Consumption Change Detection for Urban Planning: Monitoring and Segmenting Water Customers During Drought

American Geophysical Union (AGU) | March 11th, 2020

Demand management is a powerful way for water utilities to address the challenges of population growth and climate change. Although active conservation efforts have been

Demand management is a powerful way for water utilities to address the challenges of population growth and climate change. Although active conservation efforts have been studied extensively, recent evidence suggests households respond to many external events beyond a utility's control, including political responses to extreme climatic episodes and corresponding mass media coverage. Despite their importance, these external factors are difficult to analyze in a controlled setting, and few tools exist to evaluate their influence on customers. Here, we present a consumption change detection (CCD) method that offers new insights into how climate‐related mass media and policy events affect conservation by pinpointing the timing and magnitude of customer‐level water use shifts. We use CCD to monitor and segment the responses of residential water customers to policy and media events in Costa Mesa, California, during the severe 2012–2016 drought. Our results show consumption reductions among 75% of customers. Of these, 80% reduced water use before mandatory restrictions were imposed, coincident with intensifying state policy responses and spikes in media coverage that affected all customer types during 2014. Analysis of standardized drought consumption trajectories indicates that 16% of conserving customers increased consumption in 2015–2016. Conservation and rebound were both more likely among affluent and educated customers, suggesting that CCD can identify engaged and informed water savers who make suitable targets for water‐efficient retrofit incentive schemes. This study demonstrates CCD's potential as a novel demand analysis tool in an interconnected world where external social, political, and climatic stressors can exert an important influence on customer behavior.

County of San Bernardino Hydrology Manual

San Bernardino County | August 1st, 1986

Critical Aquifer Overdraft Accelerates Degradation of Groundwater Quality in California's Central Valley During Drought

American Geophysical Union (AGU) | September 1st, 2021

It has been established that wells are at risk to run dry when groundwater levels decline during drought, but associated impacts to water quality are poorly understood. 

It has been established that wells are at risk to run dry when groundwater levels decline during drought, but associated impacts to water quality are poorly understood. This study examined 30 yr of data from California's Central Valley to find dramatic groundwater-level declines during drought were associated with worsening groundwater quality. This likely happens because increased pumping during drought can draw shallow, contaminated groundwater to depths commonly tapped by public drinking water wells. This is the first study of its kind to show direct linkages between drought and groundwater quality at such a broad spatial scale

Decline of the world's saline lakes

Nature Portfolio (Springer Nature) | October 23rd, 2017

Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-t

Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

Defining Snow Drought and Why It Matters

American Geophysical Union (AGU) | February 28th, 2017

On 12 February, water resource managers at the Oroville Dam issued an evacuation warning that forced some 180,000 Californians to relocate to higher ground. The story of

On 12 February, water resource managers at the Oroville Dam issued an evacuation warning that forced some 180,000 Californians to relocate to higher ground. The story of how conditions got to this point involves several factors, but two clearly stand out: the need to prevent water shortages during a record drought, followed by one of the wettest October–February periods in California history.

Delta Salinity Management Workshops 2022 Information Sheet

Delta Stewardship Council (Delta Council) | March 7th, 2022

Designing Drought Indicators

American Meteorological Society (AMS) | November 25th, 2019

Drought indicators hold great potential to assist water management. However, drought information products are traditionally designed by scientists with little input from

Drought indicators hold great potential to assist water management. However, drought information products are traditionally designed by scientists with little input from the end users. This has resulted in an inundation of products ill suited to stakeholder needs and requirements, limiting the potential for improving management through the use of these products. In a different field—the field of product design—product designers and strategists have matured methodologies for optimizing the creation of material products, such as shoes and cars, for example, for customers. A multitude of design-centric strategies are employed to determine customer needs and requirements (e.g., lighter shoe, more cushioning, breathable, reflectivity, arch support, width options, color options). These approaches can be extended from material to information or data products. Here, we describe how the methodological approaches within the field of product design can be interdisciplinarily employed to data products for drought indicators, with water managers as end users (i.e., the “customers”). New results for drought data products may be transformative in how drought indices are constructed, communicated, and delivered, with potentially significant improvements for water management.

Development and Interpretation of Daily Seasonal Water Supply Forecasts

U.S. Department of Agriculture (USDA) | February 26th, 2009

This Technical Note documents the process used to develop the Daily Water Supply Forecast procedures and serves as a guide for helping users interpret the results. Thi

This Technical Note documents the process used to develop the Daily Water Supply Forecast procedures and serves as a guide for helping users interpret the results. This product was developed to supplement official water supply forecasts generated at the beginning of each month during the water supply season. The water resource community requested daily calibrated water supply forecasts to aid in the assessment of increased climate variability. The Natural Resources Conservation Service (NRCS) National Water and Climate Center (NWCC) developed these procedures that use hydroclimatic data collected by the SNOTEL and USGS data networks.