Phoenix, Arizona - Geography

Geography

Phoenix is located at 33°27' North, 112°4' West (33.4485°, −112.0738°) in the Salt River Valley, or "Valley of the Sun", in central Arizona. It lies at a mean elevation of 1,117 feet (340 m), in the northern reaches of the Sonoran Desert.

Other than the mountains in and around the city, the topography of Phoenix is generally flat, allowing the city's main streets to run on a precise grid with wide, open-spaced roadways.

The Salt River runs westward through the city of Phoenix; the riverbed is often dry or a trickle due to large irrigation diversions, except after the area's infrequent rainstorms or when more water is released from upstream dams. The city of Tempe has built two inflatable dams in the Salt River bed to create a year-round recreational lake, called Tempe Town Lake. The dams are deflated to allow the river to flow unimpeded during releases. Lake Pleasant Regional Park is located in Northwest Phoenix within the suburb of Peoria, Arizona

The Phoenix area is surrounded by the McDowell Mountains to the northeast, the White Tank Mountains to the west, the Superstition Mountains far to the east, and the Sierra Estrella to the southwest. Within the city are the Phoenix Mountains and South Mountains. Current development (as of 2005) is pushing beyond the geographic boundaries to the north and west, and south through Pinal County. According to the United States Census Bureau, the city has a total area of 517.9 square miles (1,341 km2); 516.7 square miles (1,338 km2) of it is land and 1.2 square miles (0.6 km², or 0.2%) of it is water.

The Phoenix Metropolitan Statistical Area (MSA) (officially known as the Phoenix-Mesa-Glendale MSA), is the 12th largest in the United States, with a total population of 4,192,887 as of the Census 2010. It includes the Arizona counties of Maricopa and Pinal. Other cities in the MSA include Mesa, Scottsdale, Glendale, Tempe, Chandler, Gilbert, and Peoria. Several smaller communities are also included, such as Cave Creek, Queen Creek, Buckeye, Goodyear, Guadalupe, Fountain Hills, Litchfield Park, Anthem, Sun Lakes, Sun City, Sun City West, Avondale, Surprise, El Mirage, Paradise Valley, and Tolleson. The communities of Ahwatukee, Arcadia, Laveen and some others are part of the city of Phoenix; Ahwatukee being separated from the rest of the city by South Mountain.

The city is the largest city in the Arizona Sun Corridor. The Sun Corridor is the 8th largest megaregion, in terms of area, in the United States of America and is predicted to be the 10th most populous megaregion in 2025. The Sun Corridor is equivalent to Indiana in size and population and had a GDP of $191 billion in 2005.

Phoenix is the nation's sixth most populous city with approximately 1.47 million people, however, with a huge land area of 516.7 square miles (1,338 km2), the city has a low density rate of about 2,797 people per square mile due to 1/3rd of its land area being undeveloped desert. By comparison, Philadelphia has approximately 1.55 million people in a land area of 135.1 square miles (350 km2), giving it a high density rate of over 11,000 people per square mile.

As with most of Arizona, Phoenix does not observe daylight saving time. In 1973, Gov. Jack Williams argued to the US Congress that energy use would increase in the evening, as refrigeration units were not used as often in the morning on standard time. He went on to say that energy use would rise "because there would be more lights on in the early morning." He was also concerned about children going to school in the dark, which indeed they were. The exception to this are lands of the Navajo Nation in Northeastern Arizona, which observe daylight saving time in conjunction with the rest of their tribal lands in other states. Phoenix is the largest US city in the Mountain Time Zone.