Case Study:
Water and Wastewater Utilities
Planning for Climate Change
SOUTHERN NEVADA WATER AUTHORITY
Background
The Southern Nevada Water Authority (SNWA) is a cooperative of seven member agencies founded in 1991 with the
collective mission to manage the region's water resources and develop solutions that will ensure adequate future water
supplies for the Las Vegas Valley. Roughly 90% of the drinking water for the SNWA region is currently sourced from the
Colorado River via Lake Mead, the largest man-made reservoir in the United States. This water is processed through two
water treatment plants to serve residential customers and businesses in Las Vegas Valley, which includes roughly 2
million people and more than 40 million annual visitors. Groundwater production provides additional water supply during
summer months.
Climate Threats
Historically, drought and population growth have complicated water management in the Southwest region of the country.
Recent extended drought has increased the challenge of maintaining a reliable supply of water and infrastructure to
access and treat supplies. In response, SNWA developed, and for the past two decades has successfully implemented,
an effective water resource plan and capital improvement plan. Despite the success of these plans' strategies, SNWA
faces significant challenges, including: the potential for continued decline in Lake Mead storage due to reduced Colorado
River streamflow, the potential loss of the ability to withdraw water from intakes, reduced water quality at intake locations,
and increased power requirements to pump water a greater vertical distance.
Planning Process
Recently, due largely to concerns about the additional impact of climate change on current drought conditions, SNWA
participated in an exercise with the U.S. Environmental Protection Agency (EPA) to demonstrate use of the Climate
Resilience Evaluation and Awareness Tool (CREAT) by beginning a climate risk assessment of overall threats to its
system and identifying opportunities for adaptation. Through a series of internal collaborations and webinars with EPA,
SNWA participants discussed their approach to risk assessment and began collecting information related to available
climate data, anticipated climate change impacts and potentially vulnerable assets.
Adaptation Measures
Based on impacts from prior drought events, SNWA has already taken action to protect its water resources and improve
the overall resilience of these resources to drought and climate change. Examples of these measures include an
extensive water conservation program and significant investment in enhancements to Lake Mead intake infrastructures.
Demand management practices (i.e., education, incentives, regulation and rates) have reduced consumptive water use by
32% since 2000, even as the population has increased by nearly half a million over the same period.
Using CREAT results, SNWA was able to evaluate a number of physical adaptation measures to address the impacts
related to declining reservoir levels. These options included infrastructure improvements to ensure operability at lower
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Case Study: Water and Wastewater Utilities Planning for Climate Change
lake levels and confirmed the need of a new intake that was already under construction. See the table below for more
potential adaptive measures that were considered, as well as those that have already been implemented by SNWA.
TYPE
CURRENT AND POTENTIAL ADAPTIVE MEASURES
New Construction
Adaptive Measures
and Enhancements
Completion of a third intake in Lake Mead accessing cooler water with lower
turbidity

Planning and constructing a low-lake level pumping station which will enable
water diversions across the full range of possible reservoir levels, including those
well below the lowest reservoir levels ever recorded since the filling of Lake
Mead in 1936

Changes to operation of groundwater wells to address water quality issues
associated with warm water in the distribution system stemming from low
reservoir levels
Conservation
Adaptive Measures
Monetary incentives for homeowners and commercial properties to convert turf
to water efficient landscapes

Partnerships with landscapers in the area to provide them with water-efficient
irrigation technology

Rebates on pool covers to prevent evaporation

Time/day restrictions on landscape irrigation, including for commercial customers
Contact Information
For more information regarding SNWA's climate adaptation planning, contact Keely Brooks at
keelv.brooks@snwa.com.
Southern Nevada Water Authority Case Study  Page 2
Office of Water (4608T)
EPA 810-S-16-002
i c/EPA
January 2017

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