Bureau of Reclamation & Santa Ana Watershed Project Authority complete Santa Ana Watershed study

(Press-News.org) Contact information: Peter Soeth
psoeth@usbr.gov
303-445-3615
Bureau of Reclamation
Bureau of Reclamation & Santa Ana Watershed Project Authority complete Santa Ana Watershed study Collaborative Report helps address impacts of climate change on the Basin's water resources WASHINGTON - Bureau of Reclamation Commissioner Michael L. Connor released the Santa Ana River Watershed Basin Study, which addresses water supply and demand projections for the next 50 years and identifies potential climate change impacts to Southern California's Santa Ana River Watershed. This study is a first of its kind for the predominately urban basin. It encompasses approximately 2,600 square miles in Orange, Riverside and San Bernardino counties and is home to more than 6 million residents.

"Basin studies are a key part of Secretary Sally Jewell's WaterSMART initiative and help us develop a clearer picture of the potential gap between water demand and available supplies," Commissioner Connor said. "This study of the Santa Ana watershed gives water managers an array of science-based tools to make key future decisions and help us identify potential ways we can meet the diverse water needs of the region's population."

The Santa Ana Watershed Basin Study, completed in partnership with the Santa Ana Watershed Project Authority, generated several tools to help SAWPA, its member agencies, and water sector stakeholders comply with California Assembly Bill 32 requirements to achieve 1990 greenhouse gas emission levels by 2020. A climate change analysis developed by Reclamation was also used by SAWPA to prepare an array of adaptation strategies to deal with the potential effects of climate change.

Ron Sullivan, SAWPA 'One Water One Watershed' Convener and Board Member of Eastern Municipal Water District, said, "Reclamation's tools and analysis link the best in climate change modeling with locally available data. With a clear picture of what the future may hold, we can move toward a more effective water management process to ensure a sustainable water future."

Authorized by the 2009 SECURE Water Act, the Basin Study analyzes future water supply and demand scenarios based on factors such as projected changes in climate, and varying levels of growth for municipal, agricultural and business interests in the Santa Ana River Watershed. Highlights of the two-year study include SAWPA and Reclamation hosting two well-attended climate change science workshops, development and analysis of basin adaptation strategies, creation of a Greenhouse Gas (GHG) Emissions Calculator for the water sector to help member agencies meet California's mandated GHG emission standards by 2020, development of a Groundwater Screening Tool, and creation of a series of 'frequently asked questions' that can assist basin water sector leaders in their decision-making.

The report found this watershed has challenges due to climate change and growing populations. The challenges in this watershed include increasing demand, earlier snowmelt and runoff, and faster than historical sea level rise threatening coastal communities, water infrastructure and groundwater basins.

"This study contributed critical information for updating our 'One Water One Watershed' Plan," said SAWPA General Manager Celeste Cantu. "Reclamation's climate change analysis helped develop effective adaptation strategies for our watershed, and provides us a strong technical foundation to start that conversation as we move toward the future."

"This study is one of several basin studies being conducted in Southern California," said Reclamation's Lower Colorado Regional Director Terry Fulp. "This program fosters a collaborative approach to examine a basin's water supply and demand challenges as well as the impacts of climate change. It also provides water resource managers critical information to help them prepare, plan, and implement adaptation strategies to address future conditions."

### The results of the study are posted on Reclamation's website at http://www.usbr.gov/watersmart/bsp/. Copies are also available on CD and can be requested by contacting Reclamation's Study Manager Jack Simes at 951-695-5310.

WaterSMART is the U.S. Department of the Interior's sustainable water initiative that uses the best available science to improve water conservation and help water resource managers identify strategies to narrow the gap between supply and demand. Basin studies are comprehensive water studies that define options for meeting future water demands in river basins in the western U.S. where imbalances in water supply and demand exist or are projected to exist. Since the program's establishment, 19 basins have been selected to be evaluated. For more information see http://www.usbr.gov/WaterSMART/bsp/.