California Institute for Water Resources › Research › Research We Conduct
Research We Conduct
Applied research for California’s water challenges.
CIWR uses systems approaches and interdisciplinary partnerships to address water management challenges. We collaborate with researchers across California universities and UC Cooperative Extension to connect research with real-world decisions, policies, and practices.

Research Areas
CIWR research spans water management, policy, systems analysis, agriculture, cities, disasters, landscapes, and research communication.
Water Policy and Planning · Water Resource Systems Analysis · Urban Water Management · Agricultural Water Management · Disaster Management · Landscape Management · Research Communication
Current Research
Current CIWR projects address sanitation, water-use efficiency, agricultural nutrient management, basin planning, and water-system finance.
California Wastewater Needs Assessment
CIWR is part of a collaborative team developing California’s first statewide assessment of water-related sanitation needs, with a focus on disadvantaged and vulnerable communities.
CIWR led the Baseline Assessment of Community Sanitation Needs, including a survey of more than 100 stakeholders. The baseline report was published in July 2025, followed by a statewide field campaign continuing through 2026.
Project Lead: Greg Pierce, UCLA Luskin Center for Innovation
CIWR Project Team: Erika Cassio Madrazo, Sam Sandoval Solis (ANR PI), Erik Porse, and Riley Currey
Project Support: California State Water Resources Control Board
Urban Water Use Efficiency and Conservation
CIWR conducts research and Extension to understand and improve urban water-use efficiency and conservation in California. The work develops models and analytical methods to evaluate benefits and impacts and to integrate demand projections into water resource planning.
The studies incorporate end-use modeling, urban landscape characterization, indoor and outdoor demand estimation, economic evaluation, and models that assess how changing demand affects wastewater generation and treatment.
Project Team: Erik Porse, Rachel Shellabarger, Hope Hauptman, and Camilo Salcedo
Collaborators: UCLA, UC Merced, Office of Water Programs at Sacramento State, and UC Riverside

SB 1157 Study: Benefits and Impacts of the Indoor Water Use Standard
In May 2025, a multi-university team led by CIWR began working with the California Department of Water Resources to quantify the benefits and impacts of California’s 2030 indoor residential water-use standard and inform its long-term implementation.
The study forecasts future water-demand and efficiency trends in California cities, evaluates connections between urban water-supply and wastewater systems, examines potential impacts on recycled-water production, and assesses affordability impacts for systems across the state. The team will provide findings to DWR by January 2028.
CIWR Team: Erik Porse, Rachel Shellabarger, Hope Hauptman, and Camilo Salcedo
Collaborators: UCLA Luskin Center for Innovation, UCLA Department of Civil and Environmental Engineering, UC Merced, Office of Water Programs at Sacramento State, and UC Riverside

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Adoption Patterns of Nitrogen Use Efficiency Practices
As part of the Nitrogen and Irrigation Initiative and in collaboration with UC Riverside, CIWR is analyzing data on nitrogen applications and adopted best management practices reported through the Irrigated Lands Regulatory Program.
Results from the Kings River Water Quality Coalition area indicate that many growers use several practices together. Twenty-six percent of fields used six practices and twenty-four percent used five.
Project Team: Erik Porse, Rachel Shellabarger, Divya Prakash, Mehdi Nemati, and Ariel Dinar
Immersive Modeling for the Colorado River Basin
Through a project led by Utah State University, CIWR conducts immersive and participatory modeling sessions for Colorado River scenario planning. Managers and water users use online models to examine the effects of assumptions for inflows, diversions, and conservation.
The project is funded for 2025–2027 and has produced studies on immersive modeling, water accounts, and the need to consider more extreme inflow scenarios in future planning.
Project Lead: David Rosenberg, Utah State University
CIWR Team: Erik Porse and Michael Jaquez
Project Support: Cooperative Institute for Research to Operations in Hydrology, University of Alabama
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Drought and Water System Finances
CIWR evaluated the effects of drought on water-utility finances for more than 200 urban water agencies in California. Statistical modeling found that drought has a significant but relatively small effect on selected financial measures.
Long-term trends in water bills and affordability are larger than the effects associated with drought alone, highlighting how long-term costs are increasingly experienced by ratepayers.
Project Team: Erik Porse, Hope Hauptman, and Riley Currey
Selected Research Tools and Completed Studies
CIWR research has also produced models, datasets, reports, and policy agendas that continue to support water planning and decision-making.
Artes: Urban Water Systems Analysis in Los Angeles
Artes simulates imported water, groundwater, stormwater, reuse, and other flows across hundreds of agencies in Los Angeles County.
The model has supported eleven peer-reviewed studies and is publicly available through HydroShare.
Wildfire and Water Supply in California
In collaboration with UCLA’s Luskin Center for Innovation, CIWR developed a research and policy agenda focused on wildfire-related threats to drinking-water quality and water-supply systems.
The report synthesizes input from interdisciplinary and cross-sector participants.
Regression Modeling for Urban Water Demand
CIWR used standardized data from more than 400 urban water suppliers to model the drivers of water demand across California.
The work supported demand forecasting and analysis of changes during the COVID-19 pandemic.
Connect with CIWR
Questions about CIWR research, project findings, data, or collaboration opportunities? Contact our team or explore additional CIWR research programs.

