A call for strategic water-quality monitoring to advance assessment and prediction of wildfire impacts on water supplies

Frontiers in Water (Frontiers) | March 13th, 2023

Wildfires pose a risk to water supplies in the western U.S. and many other parts of the world, due to the potential for degradation of water quality. However, a lack of a

Wildfires pose a risk to water supplies in the western U.S. and many other parts of the world, due to the potential for degradation of water quality. However, a lack of adequate data hinders prediction and assessment of post-wildfire impacts and recovery. The dearth of such data is related to lack of funding for monitoring extreme events and the challenge of measuring the outsized hydrologic and erosive response after wildfire. Assessment and prediction of post-wildfire surface water quality would be strengthened by the strategic monitoring of key parameters, and the selection of sampling locations based on the following criteria: (1) streamgage with pre-wildfire data; (2) ability to install equipment that can measure water quality at high temporal resolution, with a focus on storm sampling; (3) minimum of 10% drainage area burned at moderate to high severity; (4) lack of major water management; (5) high-frequency precipitation; and (6) availability of pre-wildfire water-quality data and (or) water-quality data from a comparable unburned basin. Water-quality data focused on parameters that are critical to human and (or) ecosystem health, relevant to water-treatment processes and drinking-water quality, and (or) inform the role of precipitation and discharge on flow paths and water quality are most useful. We discuss strategic post-wildfire water-quality monitoring and identify opportunities for advancing assessment and prediction. Improved estimates of the magnitude, timing, and duration of post-wildfire effects on water quality would aid the water resources community prepare for and mitigate against impacts to water supplies.

A Case Study in Interstate Resource Management: The California-Nevada Water Controversy, 1865-1955

University of California, Davis (UC Davis) | May 1st, 1973

A case study of canal seepage quantification using gain/loss method and electrical resistivity tomography in an intensively managed water resource system in the Treasure Valley, Idaho, United States

Elsevier | November 12th, 2024

Monitoring groundwater-surface water (GW-SW) interactions is essential for effectively managing the available water resources in semi-arid and arid environments. The focu

Monitoring groundwater-surface water (GW-SW) interactions is essential for effectively managing the available water resources in semi-arid and arid environments. The focus of this study was to quantify how much SW is being exchanged with the shallow GW aquifer in the Treasure Valley (TV), Idaho, USA. Previous water budgets estimated regional canal seepage without incorporating canal variability and flow measurement uncertainty. To address this, we applied both direct (gain/loss) and indirect (electrical resistivity tomography (ERT)) techniques. Direct seepage measurements were taken on canals capturing a range of different characteristics in the TV. The discrete measurements were then used to estimate the total seepage anticipated to be lost from these canals during the irrigation season. Our findings showed high seepage variability across the canals. The ERT inversion approach was utilized before and after the irrigation season by applying an advanced inversion scheme to better constrain the canal seepage spatial variability and uncertainty by quantifying changes in the saturated zone with 2D-ERT results. Temporal changes in the subsurface resistivity were observed due to the lateral flow from the nearby surface canal during the irrigation season. The combination of these approaches improves our understanding of SW-GW interactions in intensively managed irrigation systems.

A changing framework for urban water systems

American Chemical Society (ACS) | May 8th, 2013

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increas

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increasing stress as water scarcity and a growing recognition of the importance of factors other than the cost of service provision are forcing a reexamination of long-held ideas. Research and development that supports new technological approaches and more effective management strategies are needed to ensure that the emerging framework for urban water systems will meet future societal needs

A Climatology of Narrow Cold-Frontal Rainbands in Southern California

American Geophysical Union (AGU) | January 27th, 2022

Narrow cold-frontal rainbands produce short-duration (<1-hr), high-intensity precipitation associated with flash floods and debris flows in Southern California, inclu

Narrow cold-frontal rainbands produce short-duration (<1-hr), high-intensity precipitation associated with flash floods and debris flows in Southern California, including the extremely destructive 2018 Montecito event. Prior research describes development, predictability, and associated hazards of these bands, though no known long-term record of their occurrence and climatological characteristics exists within the United States. This study provides the first known catalog of narrow coldfrontal rainbands during the winter seasons of 1995–2020 in Southern California, and explores characteristics of these features such as frequency, movement, and the large-scale meteorology that drives them. Events were documented manually using rain gauge observations, radar data, and output from atmospheric models. In total, 94 rainbands were documented during the study period, with an average of three landfalling events occurring in Southern California per water year. The intensity and impacts across the recorded events varied, though common weather patterns, including strengthening cyclones near the California coast, were associated with the documented events. This catalog supports weather-forecasting efforts as well as the future development of an automated detection algorithm.

A Commitment to Action: Advancing Integrated Water Management in California

California Department of Water Resources (DWR) | September 11th, 2013

This document highlights the key perspectives and recommendations that emerged during the Integrated Water Management Summit held in Sacramento on April 3, 2013.  The Ca

This document highlights the key perspectives and recommendations that emerged during the Integrated Water Management Summit held in Sacramento on April 3, 2013.  The California Department of Water Resources (DWR) hosted the event in partnership with the Water Education Foundation and the California Water Commission, and would like to thank the 200+ attendees and guest speakers who participated in the Summit. The goal of the Summit was to bring together water leaders from myriad agencies and organizations to share experiences and ideas on how we can effectively align to provide sustainable water resources services in the State, in the face of an uncertain future. Most agree that the water management approaches we have been relying on for several decades are no longer sustainable given today’s economic climate, our changing environment and the need to supply safe drinking water, agricultural water and flood protection for a growing population, while also protecting and enhancing valuable environmental resources.  The thoughtful presentations and informative discussions at the Summit served as an important milestone in the movement to shape a more cooperative and effective approach to water management in California. The Summit launched a new campaign called “Water 360” to help refocus and strengthen the collective efforts of California’s water management community by advancing integrated water management. Integrated water management is a framework for planning and implementation that melds the objectives of improving public safety, fostering environmental stewardship and supporting economic stability to lead to sustainable water resource management. Integrated water management is not a new concept in California, and great strides have been made in the last decade to utilize the approach, particularly at the regional level. The Water 360 Campaign builds on these early successes and calls for broader application across the entire state. DWR is prepared and committed to lead this effort in close partnership with other water leaders, particularly State, federal, and local agencies; and in collaboration with all stakeholders.

A Common Vision for the Colorado River System: Toward a Framework for Sustainability

Water and Tribes Initiative | October 5th, 2020

A Community Guide for Evaluating Future Urban Water Demand

Pacific Institute | August 31st, 2016

A Community Guide for Evaluating Future Urban Water Demand provides communities, environmental groups, ratepayer advocates, and anyone interested in sustainable water sup

A Community Guide for Evaluating Future Urban Water Demand provides communities, environmental groups, ratepayer advocates, and anyone interested in sustainable water supply planning with the knowledge and tools they need to understand water demand forecasts. Communities across the U.S. are faced with decisions about how to meet the needs of a growing population. To help make these decisions, water utilities often rely on forecasts that project water use 20 or 30 years into the future, consistent with the amount of time it takes to develop new supply infrastructure, such as desalination plants or reservoirs. For much of the 20th century, water use in American cities grew in proportion to population and the economy. Since the 1980s, however, water use in communities across the United States has remained steady or declined despite continued population and economic growth, due to improved water conservation and efficiency and structural changes in the American economy. While the water sector has undergone a fundamental transformation, the practice of water demand forecasting has been slow to keep pace. Water suppliers routinely overestimate future water demand based on often overstated estimates of population and economic growth and underestimates of the effects of water conservation and efficiency improvements. These inflated estimates of future water needs can result in unneeded water supply and treatment infrastructure, higher costs to ratepayers, and unnecessary environmental impacts. The guidebook explains how water utilities forecast long-term water demand and reviews some of the approaches and methods commonly used by utilities and consultants. It also provides a set of best practices that can be used to create more accurate and robust long-range water demand forecasts. Some of these best practices include accounting for water conservation and efficiency improvements and land use changes, as well as ensuring transparency and meaningful stakeholder engagement.

A Comparative Study for Estimating Crop Evapotranspiration in the Sacramento-San Joaquin Delta

University of California, Davis (UC Davis) | April 23rd, 2018

Consumptive water use by crops, often referred to as evapotranspiration (ET), is frequently the largest component of an agricultural region’s water balance. This study

Consumptive water use by crops, often referred to as evapotranspiration (ET), is frequently the largest component of an agricultural region’s water balance. This study investigates crop consumptive use in the Sacramento-San Joaquin Delta (“Delta”) of California using a comparative approach with several prominent methods for estimating crop ET, including estimates based on crop coefficients, water balances, energy balance using remote sensing, and field measurements. Click here to download full report and links to appendices

A comparison of the taxonomic and trait structure of macroinvertebrate communities between the riffles and pools of montane headwater streams

Hydrobiologia (Springer) | May 30th, 2018

Macroinvertebrate community taxonomic and trait structure showed consistent differences between riffles and pools across 12 headwater streams in the Sierra Nevada (Cali

Macroinvertebrate community taxonomic and trait structure showed consistent differences between riffles and pools across 12 headwater streams in the Sierra Nevada (California) even as flows varied from wet to dry years and between seasons. Densities of Ephemeroptera, Plecoptera, Trichoptera, Elmidae, Orthocladiinae and Diamesinae midges, and mites were greater in riffles, whereas Tanypodinae, Chironominae, Sialis, and Pisidium were more abundant in pools. Pools had higher densities but estimated biomass was greater in riffles. Collector-gatherer and micropredator abundances were greater in pools whereas grazers, collector-filterers, and macropredators were more abundant in riffles. Stonefly shredders were most abundant in riffles but some caddis shredders were more abundant in pools. Trait state patterns were related to food resource and physical habitat differences between riffles and pools. Of the distinct pool–riffle differences we found among taxa, only about half conformed to expectations from the literature. Pool and riffle assemblages were most dissimilar at intermediate discharge and converged at low and high flows when one or the other habitat dominated. Bioassessment sampling will need to account for these flow-related differences. Benthic invertebrate communities in these mountain streams clearly differ between pools and riffles, but the relative extent of habitats and biological similarity shift with flow regime.