Water Utility Climate Alliance

Created: 4/21/2010 - Updated: 10/28/2021


The Water Utility Climate Alliance (WUCA) is a coalition formed in 2007 to help water utilities prepare for and respond to the impacts of climate change and protect water supplies. Members are located throughout the United States from southern California to New York City. WUCA develops resources to support climate-informed decision-making by water utilities and serves as a learning network for members to exchange lessons learned.


Climate change is expected to impact the hydrological cycle, affecting water supply, delivery, use, and quality. In response, water resource managers are trying to prepare and adapt systems and processes to climate change. In the past, water resource managers relied upon historical water data to plan the following year’s water distribution. However, due to climate change, the past will no longer be a good indication of the future. To help prepare for the impacts of climate change, a coalition was created to exchange ideas and to organize efforts to address future issues in water resources management.


In January 2007, the San Francisco Public Utilities Commission hosted the first Water Utility Climate Change Summit in San Francisco, California. The symposium was attended by over 200 water and wastewater utility representatives from government, private sector, and environmental groups. The purpose of the symposium was to help participants better understand the impacts of climate change on water resources and related issues. WUCA was formed after the symposium and members of the WUCA include the Central Arizona Project, Austin Water, Denver Water, Metropolitan Water District of Southern California, New York City Department of Environmental Protection, Philadelphia Water Department, Portland Water Bureau, San Diego County Water Authority, San Francisco Public Utilities Commission, Seattle Public Utilities, Southern Nevada Water Authority, and Tampa Bay Water. Key climate change factors of concern for members include:

  • Drought: Austin Water, Central Arizona Project, Denver Water, New York City Department of Environmental Protection, San Diego County Water Authority, San Francisco Public Utilities Commission, Southern Nevada Water Authority
  • Heat: Austin Water, Central Arizona Project, Denver Water, Philadelphia Water Department, Tampa Bay Water
  • Flooding: Austin Water, Tampa Bay Water
  • Sea level rise: Metropolitan Water District of Southern California, New York City Department of Environmental Protection, Philadelphia Water Department, San Francisco Public Utilities Commission, Seattle Public Utilities, Tampa Bay Water
  • Extreme weather events/changes in precipitation: Central Arizona Project, New York City Department of Environmental Protection, Philadelphia Water Department, Portland Water Bureau, Seattle Public Utilities
  • Loss of snowpack: Denver Water, Metropolitan Water District of Southern California, Portland Water Bureau, San Francisco Public Utilities Commission, Seattle Public Utilities
  • Wildfire: Denver Water

One of the major issues facing water utilities is their ability to project changes within their watershed and then develop techniques to adjust to changes due to climate change. WUCA partnered with the climate science community to develop downscaled climate models that are able to more accurately predict changes in the hydrological cycle at the sub-basin scale. WUCA worked with leaders from the Regional Integrated Sciences and Assessments (RISA) program and other scientists on the 2010–2014 Piloting Utility Modeling Applications for Climate Change (PUMA) project. PUMA’s objectives were to:

  • Identify climate modeling tools and techniques for selected WUCA members that are prepared to conduct impact assessments for their systems;
  • Identify how to use downscaled climate data in planning; and
  • Acquire climate data that can be used by WUCA members in impacts assessments, water planning, and decision making.

WUCA utilities that engaged in the PUMA project included Tampa Bay Water, Seattle Public Utilities, New York City Department of Environmental Protection, and the Portland Water Bureau. Each utility partnered with local scientific experts; these included Tampa (Southeast Climate Consortium), Seattle (Pacific Northwest Climate Impacts Research Consortium), New York (City University of New York Institute for Sustainable Cities, Columbia University, the NASA Goddard Institute for Space Studies, Cornell University, and the Consortium for Climate Risk in the Urban Northeast), and Portland (Pacific Northwest Climate Impacts Research Consortium). Common findings across all four case studies were that the utilities needed to customize climate models to make them relevant to each city’s specific situation.

Outcomes and Conclusions

WUCA has also undertaken several efforts to create resources to support utility decision making. For example, two papers—Options for Improving Climate Modeling to Assist Water Utility Planning for Climate Change and Decision Support Planning Methods: Incorporating Climate Change Uncertainties into Water Planning—were produced to support utilities identify, evaluate, and understand climate science and decision support tools that can advance adaptation action. In addition, WUCA developed a suite of case studies in 2019 exploring how water resources professionals are integrating climate change into the design and delivery of services. These case studies span different geographies and climate impacts of concern, including sea level rise (Miami, San Francisco, New York City), extreme rainfall (Seattle, Colorado, Copenhagen), heat (Dallas/Fort Worth), and drought (Southern Nevada). Near-term priorities include developing and implementing climate resilience training and creating A Field Guide to Sea Level Rise Adaptation for the Water Sector: Moving Beyond the Risk Assessment to Implementation.

Actionable Science in Practice: Co-producing Climate Change Information for Water Utility Vulnerability Assessments - The Final Report of the Piloting Utility Modeling Applications (PUMA) Project
Co-producing Actionable Science for Water Utilities
Water Utility Climate Alliance 2017–2021 Strategic Plan


Information gathered from interviews and online resources. Last updated 7/21.

Project File (s)

Water Utility Climate Alliance WUCA Member Agencies


Feifel, K. & Gregg, R. M. (2020). Water Utility Climate Alliance [Case study on a project of the Water Utility Climate Alliance]. Version 2.0. Product of EcoAdapt’s State of Adaptation Program. (Last updated July 2020)

Project Contact(s)

The Water Utility Climate Alliance is dedicated to collaborating on climate change issues affecting drinking water utilities. By enhancing climate change research and developing adaptation strategies, water utilities will be positioned to respond to climate change and protect our water supplies. In January 2007, the San Francisco Public Utilities Commission hosted the first national Water Utility Climate Change Summit, which was attended by more than 200 water and wastewater utility executives, government officials, climate change experts and environmental leaders.

The San Francisco Public Utilities Commission is a department of the City and County of San Francisco that provides retail drinking water and wastewater services to San Francisco, wholesale water to three Bay Area counties, and green hydroelectric and solar power to San Francisco's municipal departments.

The Metropolitan Water District of Southern California is a consortium of 26 cities and water districts that provides drinking water to nearly 19 million people in parts of Los Angeles, Orange, San Diego, Riverside, San Bernardino and Ventura counties. Metropolitan currently delivers an average of 1.7 billion gallons of water per day to a 5,200 square-mile service area.

The Portland Water Bureau provides the highest quality water, customer service and stewardship of the critical infrastructure, fiscal, and natural resources entrusted to our care. We enhance public health and safety and contribute to the economic viability and livability of the Portland metropolitan region. We are a recognized leader among water service agencies across the country.

The Southern Nevada Water Authority (SNWA) is a cooperative agency formed in 1991 to address Southern Nevada's unique water needs on a regional basis. SNWA is governed by a seven-member agency comprised of representatives from each of its member organizations. These member agencies are: •Big Bend Water District •Boulder City•Clark County Water Reclamation District •Henderson •Las Vegas •Las Vegas Valley Water District •North Las VegasThe member agencies provide water and/or wastewater services to Southern Nevada.

The Water Authority was formed in 1944 by the California State Legislature, and operates under the County Water Authority Act, which can be found in the California State Water Code. The Water Authority is one member of the Metropolitan Water District of Southern California, and in its 60-year history the Water Authority has come to supply up to 90% of San Diego County's water.

The New York City Department of Environmental Protection (DEP) is a City agency of nearly 6,000 employees that manages and conserves the City’s water supply; distributes more than one billion gallons of clean drinking water each day to nine million New Yorkers and collects wastewater through a vast underground network of pipes, regulators, and pumping stations; and treats the 1.3 billion gallons of wastewater that New Yorkers produce each day in a way that protects the quality of New York Harbor.


Scale of Project
National / Federal
Sector Addressed
Water Resources
Target Climate Changes and Impacts
Air temperature
Flow patterns
Infrastructure damage
Salinization / Saltwater intrusion
Sea level rise
Storms or extreme weather events
Water quality
Water supply
Climate Type
Type of Adaptation Action/Strategy
Capacity Building
Design or reform institutions
Create new institutions
Increase organizational capacity
Coordinate planning and management
Conduct / Gather additional research, data, and products
Conduct vulnerability assessments and studies
Infrastructure, Planning, and Development
Infrastructure retrofitting and improvements
Stormwater systems: retrofitting and improvements
Water supply: retrofitting and improvements
Governance and Policy
Sociopolitical Setting
Effort Stage
In progress

Related Resources

Adaptation Phase
Sharing Lessons
Sector Addressed
Climate Justice
Conservation / Restoration
Disaster Risk Management
Education / Outreach
Land Use Planning
Rural / Indigenous Livelihoods
Transportation / Infrastructure
Water Resources
Read more