Energizing Water Efficiency: California Energy Sector Experiences Can Advance State’s Water Conservation and Efficiency

Pacific Institute | December 29th, 2013

As a dry December accentuates the stress on California’s limited water supplies, the success of the state’s energy sector in implementing efficiency programs offers v

As a dry December accentuates the stress on California’s limited water supplies, the success of the state’s energy sector in implementing efficiency programs offers valuable lessons to the water sector. A new report from the Pacific Institute examines the rules, regulations, and policies that promote energy efficiency and finds models for water management in drivers like the energy sector’s appliance standards, building codes, pricing policies, and utility-sponsored efficiency programs. California has made remarkable improvements in energy efficiency over the last several decades and is recognized as a national leader. The state’s per capita electricity and natural gas consumption is about 45% and 30% less, respectively, than other Americans. Indeed, California’s per capita electricity consumption has remained largely unchanged since the mid-1970s – while increasing by more than 50% across the U.S.  Efficiency policies, including incentive and education programs, have been a major factor in reducing per capita energy use in California. In water conservation and efficiency, California has also made major advances. Many urban areas across the state, including Los Angeles and San Francisco, are serving a larger population with the same or even less water than 20 years ago. But with increasing pressure on water supply from population and economic growth, the need to restore freshwater ecosystems, and climate change, greater water conservation and efficiency are essential. “Reductions in per-capita water demand have been driven first by a shift to a less water-intensive service-oriented economy, and second by federal, state, and local policies as well as utility programs facilitating water-efficiency improvements,” said Heather Cooley, co-director of the Pacific Institute Water Program. “We must examine new approaches for achieving even greater savings to address the water challenges we now face.” The Pacific Institute report identifies programs that have worked for the energy sector and offers recommendations for how they could be adapted to the water sector. First among them are to continuously update standards and codes for fixtures and buildings to capture new technologies and practices.

Equity in Stormwater Investments: Measuring Community Engagement and Disadvantaged Community Benefits for Equitable Impact in the Safe Clean Water Program

Publisher not available | August 4th, 2022

The Safe, Clean Water Program (SCWP) reflects the will of the voters of Los Angeles County, who approved Measure W in 2018 by close to 70%. The ballot measure established

The Safe, Clean Water Program (SCWP) reflects the will of the voters of Los Angeles County, who approved Measure W in 2018 by close to 70%. The ballot measure established a perpetual parcel tax “to fund projects and programs to increase stormwater capture and reduce stormwater and urban runoff pollution” in Los Angeles County “to increase water supply, improve water quality, and, where appropriate, provide community enhancements such as the greening of schools, parks, and wetlands, and increased public access to rivers, lakes, and streams.” In an ordinance implementing the Safe Clean Water Program, the county Board of Supervisors included provisions to prioritize equity in implementation and affirmed an intention to address inequity in infrastructure in August 2021. Those provisions gave rise to this report, which provides advice drawn from research and stakeholder engagement to the Los Angeles County Flood Control District (LACFCD) for measuring community engagement and Disadvantaged Community Benefits to better achieve the equitable impact sought by the SCWP. As part of a broader SCWP Metrics and Monitoring Study (MMS) commissioned by the LACFCD, we were charged with conducting research, consulting with stakeholders, and giving advice to the SCWP for metrics to measure community engagement and Disadvantaged Community Benefits.

Estimation of residential outdoor water use in Los Angeles, California

Landscape and Urban Planing (Elsevier) | July 1st, 2014

The current study analyzes existing methods for estimating outdoor use and landscape irrigation in highly developed residential areas across Los Angeles. Outdoor use was

The current study analyzes existing methods for estimating outdoor use and landscape irrigation in highly developed residential areas across Los Angeles. Outdoor use was estimated using three methods: two methods described by the Pacific Institute and a third approach that utilizes remotely sensed vegetation and water billing data. Monthly individual water use records were provided by the Los Angeles Department of Water and Power (LADWP) for 2000–2010. This period includes voluntary and mandatory restrictions due to drought conditions across the state. Records were aggregated to the census tract level to protect customer privacy. The two Pacific Institute methods, which are based on water billing data, generally underestimate outdoor use due to assumptions that the lowest water consumption month represents indoor use, which is likely not the case in Los Angeles. The remote-sensing model developed between single-family water use and the Landsat normalized difference vegetation index (NDVI) surplus performed well in greener areas of the city and indicates that landscape irrigation use represents 54% of total single-family water use. The model also predicts an average decrease in landscaping irrigation of 6% and by 35% during voluntary and mandatory restrictions, respectively. Voluntary conservation and mandatory waste restrictions were less effective for higher income groups in the city, while more stringent pricing and non-pricing mandatory restrictions in FY2010 had similar effects across income groups. Study results contribute to a better understanding of the partitioning of Los Angeles residential water use and can be utilized to evaluate pricing structures and target water conservation efforts.

Evaluating effects of potential urban water use efficiency standards (AB 1668-SB 606) on urban retail water suppliers, wastewater management agencies, and urban landscapes (trees and urban parklands)**

California State Water Resources Control Board (SWRCB) | January 15th, 2022

Click here for the draft report segment on wastewater.

Click here for the draft report segment on wastewater.

Evaluating effects of urban water use efficiency standards (AB 1668- SB 606) on urban retail water suppliers, wastewater management agencies, and urban landscapes (trees and urban parklands)*

California State Water Resources Control Board (SWRCB) | January 15th, 2022

Click here for the companion draft chapter on trees and parkland

Click here for the companion draft chapter on trees and parkland

Evaluating the Effects of Turf-Replacement Programs in Los Angeles County

University of California, Los Angeles (UCLA) | August 4th, 2017

In 2014, the Metropolitan Water District of Southern California (MWD) undertook an unprecedented investment to incentive turf replacement throughout Southern California i

In 2014, the Metropolitan Water District of Southern California (MWD) undertook an unprecedented investment to incentive turf replacement throughout Southern California in response to the state’s serious drought. MWD devoted $350 million to the program, resulting in more than 46,000 rebate payments to remove 165 million square feet of turf. The funding boost served as a tremendous natural experiment to better understand the effects turf replacement programs. As part of an evaluation of this program, UCLA and the University of Utah examined socio-economic and demographic characteristics of program participation and assessed changes in vegetation and landscapes of front yards resulting from turf replacement. We examined address-level records of 24,921 participants who applied for turf replacement rebates between February 2014 and April 2016 in Los Angeles (LA) County. We analyzed the socioeconomic and spatial determinants of program participation. Further, we used Google Earth Street View to characterize the landscapes and plants resulting from turf replacement based on a set of randomly selected participating properties. We ascertained the types of turf replacements that were installed and developed a classification system for landscape design types.

Evaluating the hydrologic effects of the 2021–2022 Scott and Shasta irrigation curtailments using remote sensing and streamflow gages

Klamath Tribal Water Quality Consortium | September 11th, 2023

Key Points • Satellite remote sensing data indicated that curtailment orders in 2022 reduced consumptive water use (evapotranspiration, ETa) on agricultural lands i

Key Points • Satellite remote sensing data indicated that curtailment orders in 2022 reduced consumptive water use (evapotranspiration, ETa) on agricultural lands in Shasta Valley, but not Scott Valley. • Streamflow gage data indicate that flows in the Shasta River and some Scott River tributaries (Shackleford and French creeks) were substantially higher in summer 2022 than 2020 or 2021, but similar increases did not occur in the mainstem Scott River. • A likely major reason for the lack of Scott River flow increases was that groundwater use was allowed to continue under Local Cooperative Solutions (LCS) agreements in which water users agreed to reduce pumping by 30% from a prior year baseline. Despite abundant worldwide evidence that reducing consumptive use (i.e., evapotranspiration) is key to increasing environmental water, all LCS cropping and irrigation practices were given equal weight toward the 30% reduction, regardless of the effects on consumptive use. Pumping was not measured and compliance was primarily self-reported, with limited independent verification.

Evapotranspiration of urban landscapes in Los Angeles, California at the municipal scale

American Geophysical Union (AGU) | May 24th, 2017

Evapotranspiration (ET), an essential process in biosphere-atmosphere interactions, is highly uncertain in cities that maintain cultivated and irrigated landscapes. We e

Evapotranspiration (ET), an essential process in biosphere-atmosphere interactions, is highly uncertain in cities that maintain cultivated and irrigated landscapes. We estimated ET of irrigated landscapes in Los Angeles by combining empirical models of turfgrass ET and tree transpiration derived from in situ measurements with previously developed remotely sensed estimates of vegetation cover and ground-based vegetation surveys. We modeled irrigated landscapes as a two-component system comprised of trees and turfgrass to assess annual and spatial patterns of ET. Annual ET from vegetated landscapes (ETveg) was 11106 53 mm/yr and ET from the whole city (vegetated and nonvegetated areas, ETland) was three times smaller, reflecting the fractional vegetation cover. With the exception of May and June, monthly ETland was significantly higher than predicted by the North American Land Data Assimilation System. ETveg  was close to potential ET, indicating abundant irrigation inputs. Monthly averaged ETveg varied from 1.560.1 mm/d (December) to 4.360.2 mm/d (June). Turfgrass was responsible for 70% of ETveg. For trees, angiosperm species (71% of all trees) contributed over 90% to total tree transpiration, while coniferous and palm species made very small contributions. ETland was linearly correlated with median household income across the city, confirming the importance of social factors in determining spatial distribution of urban vegetation. These estimates have important implications for constraining the municipal water budget of Los Angeles and improving regional-scale hydrologic models, as well as for developing water-saving practices. The methodology used in this study is also transferable to other semiarid regions for quantification of urban landscape ET.

Exploring the Potential for Water-Limited Agriculture in the San Joaquin Valley

Public Policy Institute of California (PPIC) | July 21st, 2022

The rollout of California’s Sustainable Groundwater Management Act (SGMA) is altering the state’s agricultural landscape. As groundwater sustainability measures are

The rollout of California’s Sustainable Groundwater Management Act (SGMA) is altering the state’s agricultural landscape. As groundwater sustainability measures are implemented and water scarcity increases, at least half a million acres are projected to come out of irrigated production in the San Joaquin Valley, the state’s agricultural heartland. Rather than widespread land idling—which comes with unintended consequences such as dust, weeds, pests, and soil degradation — a switch from summer irrigated crops to winter crops produced with limited water (including winter cereals and forage crops, among others) might keep some of this land in production. Although water-limited agriculture faces large hurdles, some promising aspects warrant further exploration.

Field-scale crop water consumption estimates reveal potential water savings in California agriculture

Nature Portfolio (Springer Nature) | March 25th, 2024