Revision as of 13:59, 10 May 2013

Summary

The Las Vegas Valley, which includes the city of Las Vegas and the surrounding municipalities, is located in the Mojave Desert in Southern Nevada. Like most desert cities, Las Vegas exists because of water; the artesian springs of the Las Vegas Valley provided an ample water supply for Native Americans, ranchers and later a small railroad city. However, population growth increased demands far beyond local supplies. The area now depends on the Colorado River for the majority of its water supply. Natural scarcity, population growth and climate variability all contribute to the Valley’s water management challenges. This analysis addresses the following questions: 1) How can cooperation lead to better water demand management? 2) What conditions enable effective cooperation? The case demonstrates that a well-structured cooperative agency can prompt joint action by decreasing competition over water supplies. The Southern Nevada Water Authority (SNWA), a regional water utility made up of five water suppliers, was formed out of the water crisis that stuck the Las Vegas Valley in the late 1980s. Although the scarcity was key enabling condition for the creation of the SNWA, the transition would not have been as successful without the strong leadership present. Since its formation, the SNWA has fostered cooperation among the five water suppliers and contributed to substantial per capita demand reductions. However, as population growth continues and climate change exacerbates natural variability, the SNWA and its members will need to adapt to continue providing reliable water supply.

Natural, Historic, Economic, Regional, and Political Framework

The Las Vegas Valley is located in the Mojave Desert in Southern Nevada and receives about 10 cm (4 inches) of rainfall a year. Area municipalities rely on both groundwater and the Colorado River for water supply. Fast growing urban areas and a booming tourism industry have stressed water supplies. Natural climate variability with periodic droughts has further challenged water providers; projected climate changes will exacerbate these challenges.

Demographics

American settlement of Las Vegas began in 1855 when a group of Mormons built a settlement based around irrigated agriculture (Harrison 2009). Soon after the Mormons abandoned the valley but ranching and irrigated agriculture continued. The town of Las Vegas was formed in 1905 as a railroad way station (Douglass & Raento 2004). At the beginning of the 19th century, Las Vegas was a typical small western town. It grew rapidly in the 1920’s and 30’s, fueled by federal spending and an influx of workers for the Hoover Dam; government spending again fueled growth in the 1950’s as atomic testing and military training was conducted outside Las Vegas (Jones & Cahlan 1975). The rapid growth continued into the early 2000’s with Las Vegas being the fastest growing city, in the fastest growing state since World War II as seen in Figure 1 (Douglass & Raento 2004). In addition to rapid population growth, Las Vegas has been a significant tourist destination since the 1930’s. Gambling was legalized in the 1931 and by 1935 Las Vegas was already established as a marriage destination due to California’s three day waiting period for a marriage license; Hoover Dam attracted new visitors and tourism further expanded in 1941 with the start of the resort industry (Jones & Cahlan 1975). Tourism continued to grow and Las Vegas saw a huge boom in tourism with annual visitors steadily increasing from 1970 until the mid-1990’s as seen in Figure 2 (LVCLA 2013).

Water Supply & Demand

Groundwater

Groundwater was the historic water supply of the Las Vegas Valley. The local groundwater system is a two layer aquifer system consisting of a near surface aquifer and a deeper artesian aquifer. Recharge in the near surface layer is predominately from over irrigation and urban runoff while higher precipitation (around 50 cm or 20 inches per year) in the Mountain ranges surrounding the valley recharges the deep aquifer (Morris et al 1997). Historically, artesian springs could be found throughout the valley and were used by the Native American population for centuries (Morris et al 1997). Groundwater remained the primary source of water for the Valley until the early 1970’s. However, as the city grew groundwater usage quickly surpassed sustainable yield. Some areas of the Valley saw as much as a 45 m (150 ft) drop in groundwater levels from 1945 to 1995 (Morris et al. 1997), and in 1962 the Las Vegas springs first stopped flowing to the surface (LVVWD 2013). Today groundwater is still an important water source for the area and SNWA manages a mix of local and regional groundwater systems to supplement the Colorado River supply (SNWA 2009).

Surface Water

The Hoover Dam and Lake Mead Reservoir were completed in 1936 to provide storage and water supply for California, Arizona and Nevada. At the time Las Vegas still had sufficient groundwater to cover its demands and its use of the Colorado River water did not begin until two decades later. In 1955, the Las Vegas Valley Water District signed an agreement with Basic Magnesium, Inc., a private company, to use their existing pump station and pipeline (Jones & Cahlan 1975). In the early 1960’s the LVVWD began designing the Southern Nevada Water System which consisted of an in-take structure at Lake Mead, treatment works and distribution system; the first stage of the project, in-take No. 1, was complete in 1971. The second stage of the project, in-take No. 2, was completed in 1982 increasing capacity to 400 million gallons per day (MGD) (LVVWD 2013). In the early 2000’s drought conditions, as seen in Figure 3, threatened in-take No. 1 which would be out of service if Lake Mead levels dropped below 1050 feet. In 2005, the Southern Nevada Water Authority board authorized the construction of a third and lower in-take structure which is scheduled for completion in 2014 (SNWA 2013).

Analysis, Synthesis, and Insight

ASI:Formation of the SNWA: Cooperation in Demand Management

The formation of the Southern Nevada Water Authority stems from the stakeholders recognition of their interdependence. This case demonstrates that stakeholders need for cooperation, and therefore their willingness to cooperate, increases in proportion to the stresses on the system. It also demonstrates that good leadership was instrumental to the success of the Authority in controlling water demands and acquiring water supplies.(read the full article... )

Contributed by: Margaret Garcia (last edit: 20 May 2013)