KENNEY, KLEIN, AND CLARK
<br />policies to deal with the crisis. This paper documents
<br />the various approaches they used and evaluates if vol-
<br />untary and/or mandatory restrictions were effective
<br />in reducing water consumption and if so, to what
<br />extent. This information is useful in a variety of ways:
<br />e.g., in evaluating the effectiveness of actions taken in
<br />2002; for comparing (and presumably learning from)
<br />the different approaches across the eight regions; in
<br />evaluating and designing future strategies for
<br />drought coping; and perhaps in illuminating potential
<br />opportunities for achieving longer term conservation
<br />savings. This information is useful not only to water
<br />managers, but to city council members and other local
<br />officials called upon to design, enact, and enforce
<br />emergency measures.
<br />TABLE 1. Population and Growth Rates of Study Regions.
<br />Municipality
<br />Estimated
<br />2002
<br />Population
<br />Average Annual
<br />Change in
<br />Population
<br />1999 to 2001
<br />(percent)
<br />Aurora
<br />289,325
<br />2.0
<br />Boulder
<br />94,621
<br />-0.1
<br />Denver Water
<br />1,100,000
<br />4.0
<br />Fort Collins
<br />125,953
<br />2.8
<br />Lafayette
<br />24,309
<br />3.2
<br />Louisville
<br />18,914
<br />-0.2
<br />Thornton
<br />93,363
<br />5.6
<br />Westminster
<br />104,642
<br />1.7
<br />Total
<br />1,851,127
<br />periods by using reservoir storage, replenished annu-
<br />ally by snowmelt cascading down the mountains in
<br />the late spring and early summer. However, three
<br />forces have conspired in recent years to increase the
<br />region's vulnerability to water shortages (Nichols et
<br />al., 2001). First, Colorado emerged as the nation's
<br />third fastest growing state, with an approximately 31
<br />percent population increase during the 1990s (U.S.
<br />Census Bureau, 2001). Second, proposals to build new
<br />water storage projects, such as the locally infamous
<br />Two Forks Dam, were blocked by legal and political
<br />opposition, prompting cities to service growing popu-
<br />lations with existing reservoir storage and newfound
<br />conservation savings, effectively reducing the regional
<br />drought cushion (Luecke, 1999). Third, the state
<br />enjoyed one of the longest periods of wet weather
<br />since, 1929, thereby hiding the potential consequences
<br />of the inevitable next drought (McKee et al., 1999).
<br />The winter of 2001 to 2002 was abnormally warm
<br />and dry. Precipitation throughout the first four
<br />months of 2002 in the South Platte basin ranged from
<br />a high of 73 percent of average in February (NRCS,
<br />2002c) to a low of 31 percent of average in April
<br />(NRCS, 2002d), a time of year usually characterized
<br />by heavy (water laden) snows. By May 31, snowpack
<br />in the two major basins serving the Front Range —
<br />the South Platte and Upper Colorado — were at 23
<br />percent and 28 percent, respectively, of the long term
<br />average (NRCS, 2002b). Similarly, water storage in
<br />these basins had dropped to just over 80 percent of
<br />the long term average, a figure that could not be sus-
<br />tained very long given the low snowmelt and the com-
<br />ing summer months of municipal lawn watering
<br />(NRCS, 2002a). By summer, the entire state of Col-
<br />orado was in an extreme drought (NOAA, 2002).
<br />DROUGHT CRISIS AND RESPONSE
<br />The Drought Crisis of Summer 2002
<br />Demand Management
<br />Colorado is no stranger to drought, defined by the
<br />state as occurring when "a normal amount of mois-
<br />ture is not available to satisfy an area's usual water -
<br />consuming activities" (State of Colorado, 2002).
<br />Receiving an average of only 17 inches of precipita-
<br />tion a year, Colorado has experienced several
<br />droughts in the past 110 years of observed weather
<br />data, most notably in the 1930s, 1950s, mid- 1970s,
<br />and 1980 to 1981 (McKee et al., 2000). In addition,
<br />tree ring reconstructions indicate that persistent and
<br />severe droughts in the area were not uncommon in
<br />the 19th Century (Jain et al., 2002).
<br />Historically, municipalities along Colorado's north-
<br />ern Front Range - the north -south string of cities
<br />anchored by Denver in the rain shadow east of the
<br />Rocky Mountains — have been able to withstand these
<br />In response to low water storage and high demand,
<br />municipalities throughout the region scrambled to
<br />design and institute emergency demand management
<br />programs. A May 2002 report from the Colorado
<br />Water Conservation Board (CWCB) found that only
<br />22 percent of the region's municipalities already had a
<br />drought response plan in place (CWCB, 2000, unpub-
<br />lished report). Efforts inevitably focused on restrict-
<br />ing outdoor water use, particularly lawn watering,
<br />which accounts for well over half of annual residential
<br />water use and much more than half during the hot
<br />and dry Colorado summers (Mayer et al., 1999). The
<br />exact nature of the programs and the intensity of
<br />their application, however, varied significantly from
<br />city to city, as each municipal water system had a dif-
<br />ferent level of vulnerability, and was overseen by dif-
<br />ferent water agencies and local governments. While
<br />JAWRA 78 JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION
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