U.S. cities running out of water

Thomas C. Frohlich | 24/7 Wall St.

Show Caption Hide Caption U.S. cities running out of water The cities with the worst drought conditions in the country are all located in California, which is now entering its fourth consecutive year of drought as demand for water is at an all-time high.

The nine cities with the worst drought conditions in the country are all located in California, which is now entering its fourth consecutive year of drought as demand for water is at an all-time high. The long-term drought has already had dire consequences for the state's agriculture sector, municipal water systems, the environment, and all other water consumers.

Based on data provided by the U.S. Drought Monitor, a collaboration between academic and government organizations, 24/7 Wall St. identified nine large U.S. urban areas that have been under persistent, serious drought conditions over the first six months of this year. The Drought Monitor classifies drought by five levels of intensity: from D0, described as abnormally dry, to D4, described as exceptional drought. Last year, 100% of California was under at least severe drought conditions, or D2, for the first time since Drought Monitor began collecting data. It was also the first time that exceptional drought — the highest level — had been recorded in the state. This year, 100% of three urban areas in the state are in a state of exceptional drought. And 100% of all nine areas reviewed are in at least extreme drought, or D3.

According to Brad Rippey, a meteorologist with the United States Department of Agriculture (USDA), California has a Mediterranean climate in which the vast majority of precipitation falls during the six month period from October through March. In fact, more than 80% of California's rainfall is during the cold months. As a result, "it's very difficult to get significant changes in the drought picture during the warm season," Rippey said. He added that even when it rains during the summer, evaporation due to high temperatures largely offsets any accumulation.

A considerable portion of California's environmental, agricultural, and municipal water needs depends on 161 reservoirs, which are typically replenished during the winter months. As of May 31, the state's reservoirs added less than 6.5 million acre-feet of water over the winter, 78% of the typical recharge of about 8.2 million acre-feet. A single acre-foot contains more than 325,000 gallons of water. This was the fourth consecutive year that reservoir recharge failed to breach the historical average.

Normally, current reservoir levels are high enough to buffer against drought. However, "after four years of drought, reservoir holdings are perilously low," said Rippey. Current total storage levels are at about 17.2 million acre-feet. The typical annual withdrawal is around 8 million acre-feet, which means total storage may fall below 10 million acre-feet by the end of the summer. This also means there is little room for error if the state enters a fifth year of drought.

In addition to surface water, groundwater is a major water source for the state, particularly during periods of drought. According to a recent U.C. Davis analysis of the California drought from 2012 through 2014, groundwater may replace as much as 75% of surface water lost to dry conditions this year. As Rippey explained, however, the problem is that the amount of groundwater is unknown. "The monitoring system for groundwater is not nearly as robust as the surface water monitoring system," Rippey said.

City and state officials have reacted to the long-term drought by imposing various water restrictions. According to the California Department of Water Resources, California declared a statewide emergency during the 2007-2009 California drought — the first in U.S. history. California declared another such emergency during the 2012-2014 drought, and statewide precipitation was the driest three-year period on record. In an attempt to curb water use, statewide regulations impose penalties for exceeding water consumption budgets. Using water on lawns, for car washes, or to clean driveways is banned or restricted in each of the nine cities.

There are also economic consequences. The U.C. Davis study estimated a loss of at least 410,000 acres of farmland due to water shortages in California's Central Valley, one of the nation's most important agricultural zones and the location of most of the cities running out of water. An estimated $800 million was lost in farm revenue last year. That total does not include $447 million in extra pumping costs sustained by the Central Valley. Researchers at U.C. Davis estimated a total statewide revenue loss of $2.2 billion, and more than 17,000 jobs lost in 2014 due to drought.

The U.S. Drought Monitor is produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the USDA and the National Oceanic and Atmospheric Administration (NOAA). 24/7 Wall St. identified the nine urban areas with populations of 75,000 or more where the highest percentages of the land area was in a state of exceptional drought in the first six months of 2015. All data are as of the week ending June 2.

These are the U.S. cities running out of water, all of them in California.

1. Hanford

> Exceptional drought coverage (first half of 2015): 100%

> Extreme drought coverage (first half of 2015): 100%

> Population: 87,941

With 100% of Hanford covered by exceptional drought conditions, the city is tied with Merced, Modesto, and Fresno for the worst drought conditions in the nation. Like the other three cities, Hanford, too, is located in the Central Valley. In addition to statewide restrictions as well as city emergency regulations already in place, city officials adopted additional water restrictions this June, such as barring serving of water at restaurants other than by request as well as vehicle and driveway washing bans. In addition to water restrictions and crop and environmental damage, the drought has impacted the region's air quality. According to a recent report from the American Lung Association, Hanford had nearly the worst air pollution of any U.S. city. The report identified the dry, hot summers and stagnant air as key contributing factors to high concentrations of particulate matter and smog.

2. Merced

> Exceptional drought coverage (first half of 2015): 100%

> Extreme drought coverage (first half of 2015): 100%

> Population: 136,969

Merced is in the Central Valley, an agricultural hub, which not only accounts for a considerable portion of California's economic output, but also supports the majority of the nation's agricultural production. The agricultural sector in the Merced metro area accounted for 13.1% of area employment, far higher than the comparable nationwide proportion of 2%. Agricultural businesses suffer more than perhaps any other industry during severe drought conditions. Agricultural employment shrank by 12.5% in Merced from 2012 through 2013, and the drought has only worsened since then. Over the first half of 2014, exceptional drought covered 78% of Merced, one of the highest percentages in the nation at that time. Over the same period this year, 100% of the city was at the maximum drought level.

3. Modesto

> Exceptional drought coverage (first half of 2015): 100%

> Extreme drought coverage (first half of 2015): 100%

> Population: 358,172

Like several other drought-stricken cities, Modesto is located in California's Central Valley between the Sierra Nevada mountains and the San Joaquin River, which are both essential sources of water for the region. Lack of precipitation during the area's multi-year drought and particularly over this past winter has resulted in record-low snowmelt levels in the mountains. In addition, the San Joaquin River supplies 34 reservoirs, which together are at 39% of their capacity as of the end of May. One of the city's major sources of water is the Modesto Reservoir, which draws water from the Tuolumne River. The reservoir is smaller than most in California. Over the past four years, the reservoir's water levels reached their lowest point in September 2012 and are currently just below the historical average.

4. Fresno

> Exceptional drought coverage (first half of 2015): 100%

> Extreme drought coverage (first half of 2015): 100%

> Population: 654,628

All of Fresno has endured at least moderate drought conditions during the first half of each year since 2012. For the first time this year, 100% of the city was in a state of exceptional drought, up from 75% in the same period in 2014, and one of only four urban areas experiencing maximum drought conditions in their entire area. Like in many parts of California and several other cities suffering the most from drought, Fresno's economy relies heavily on agriculture. A major source of water in Fresno is groundwater pumped from aquifers, or natural underground basins. In addition, water is delivered directly from the Sierra Nevada mountains to replenish dwindling surface water levels. Precipitation over the winter was yet again disappointing, and snowpack in the Sierra Nevada mountains was measured at a record low this past April. Best and worst states to be unemployed

5. Yuba City

> Exceptional drought coverage (first half of 2015): 95.4%

> Extreme drought coverage (first half of 2015): 100%

> Population: 116,719

Yuba City is located on the Feather River, which runs south through Sacramento. The river begins at Lake Oroville, the site of the Oroville Dam and the source of the California Aqueduct — also known as the State Water Project (SWP). The dam's water levels reached a record low in November 2014. While water levels have increased considerably since then, they remain at a fraction of the reservoir's capacity. More than 95% of Yuba City was in a state of exceptional drought over the first six months of the year, making it one of only five urban areas to have exceptional drought covering more than 90% of their land area. Like other areas suffering the most from drought, the proportion of Yuba's workforce employed in agricultural jobs is several times greater than the national proportion. The drought has had considerable economic consequences in the region. Agricultural employment dropped 30.3% from 2012 through 2013, versus the nearly 2% nationwide growth.

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