• California’s water supplies are particularly vulnerable to climate change due to the risk of fluctuating sea levels, reduced mountain snowpack, increasing water demands and changes in precipitation.

file under: North America, Program Management, Water, Education

Helping Water Agencies Navigate Change

A Climate Change Handbook for Regional Water Planning

In the last decade, California, USA, has experienced some of its driest years on record—prompting the need for aggressive water supply planning. The state’s water supplies are particularly vulnerable to climate change due to the risk of fluctuating sea levels, reduced mountain snowpack, increasing water demands and changes in precipitation.

CDM Smith’s work on this project resulted in a product that is well organized and clear, highlights the key decision points and considerations, and provides the technical information needed to support decisions. 

To help assess and manage these and other risks, CDM Smith partnered with the California Department of Water Resources (DWR) and the U.S. Environmental Protection Agency Region 9 to produce the Climate Change Handbook for Regional Water Planning. The U.S. Army Corps of Engineers and the Resources Legacy Fund—a California-based philanthropic group that supports water conservation—also supported this critical project.

“The handbook is intended to provide useful information for everyone from engineers and planners to decision makers,” says Andrew Schwarz, DWR project manager. Completed in December 2011, the handbook provides guidance on incorporating climate change management into watershed management planning. Topics covered include the relationships among energy, water and greenhouse gas emissions; climate change vulnerability and impacts; and resource management strategies.

Collaborating for Success
The handbook is a significant achievement because it is one of the country’s first efforts to integrate climate change and regional water planning, according to Thomas Quasebarth, CDM Smith vice president and project manager. Both funding and developing the handbook were the result of successful collaboration.

“This is a unique partnership of nongovernmental, state and federal agencies coming together and providing an innovative, analytical framework for regional planners to consider climate change impacts,” says Quasebarth. “Though some of the details of the handbook are specific to California’s integrated regional water management planning process, the overall process is consistent with what other areas call watershed management, making it very applicable to other states and regions.”

To ensure the handbook’s content would have practical application, the project team consulted with a range of stakeholders, involving the leadership agencies of regional watershed groups throughout California. Workshops were held to engage participants in writing the handbook, and there were several opportunities for stakeholders to review and provide feedback.

EPA Climate Change Handbook Water SupplyAssessing Risk
The Climate Change Handbook for Regional Water Planning opens with a discussion on broad issues in water and climate change, and addresses regional vulnerability to climate change. In addition, the handbook provides resources to help users evaluate their vulnerability, including a vulnerability assessment checklist.

“This is a valuable starting point that gives water managers a way to examine risks,” explains Dan Rodrigo, CDM Smith vice president, who led the process development and provided technical oversight. “For instance, if you’re near the coast, what are the potential impacts of sea level rise? What about inland flooding risks? Could climate change reduce your water supplies, or increase your water demand? Once you know your vulnerability, you can focus your resources where they will have the greatest effect.”

Additional discussion is given to measuring climate change impacts by region, managing resources and implementing projects. Case studies are incorporated throughout the document, giving a user-friendly approach to illustrating relevant work that has been done, various projects that have been implemented and lessons learned.  

Planning for Uncertainty
The handbook introduces strategies for implementing projects under uncertain conditions and two guiding approaches for the future of watershed management: climate change mitigation—how to reduce greenhouse gas emissions—and climate change adaptation—how to reduce the impacts of climate change.

This is where the handbook will play a critical role, notes Quasebarth. “Here, we are suggesting new methods— tools, modeling, technology—that will really help regional planning entities understand and plan for the uncertainty surrounding water issues that is likely to exist going forward.”

In the past, adds Rodrigo, much of the available guidance discussed mitigation strategies to minimize greenhouse gas emissions. “While reducing emissions in the long term is important, it is very likely that impacts to our water resources will occur within the next 10 to 30 years and therefore, we also need adaptation strategies in place to reduce the effects of climate change.” Reuse of treated wastewater, water conservation, low-impact development, rainwater harvesting and seawater desalination are all examples of adaptation strategies that will reduce the impacts of climate change.

Visit bit.ly/cchandbook for more information on the Climate Change Handbook for Regional Water Planning.