Near Puerco Pueblo in Petrified Forest National Park
|States||Arizona, New Mexico|
|Source||near Hosta Butte|
|- location||McKinley County, New Mexico|
|- elevation||7,930 ft (2,417 m) |
|Mouth||Little Colorado River|
|- location||near Holbrook, Navajo County, Arizona|
|- elevation||5,102 ft (1,555 m) |
|Length||167 mi (269 km) |
|Basin||2,654 sq mi (6,874 km2)|
|Discharge||for near Chambers, Arizona|
|- average||70 cu ft/s (2 m3/s)|
|- max||17,800 cu ft/s (504 m3/s)|
|- min||0 cu ft/s (0 m3/s)|
The mouth of the Puerco River
on the Little Colorado River, northeast-central Arizona
The Puerco River in northwestern New Mexico and northeastern Arizona flows through arid terrain including the Painted Desert. The main tributary of the Little Colorado River, it drains an area of about 2,654 square miles (6,870 km2) and is 167 miles (269 km) long. The river's average discharge is very low, less than 70 cubic feet per second (2.0 m3/s) in normal years, because its drainage basin is extremely dry. For most of the year, the river is a braided wash containing little or no water, although large flash floods can occur in downpours. Navajos in the Puerco River valley have used surface waters in the river for livestock watering for decades. From the 1950s to the early 1980s, the Puerco ran almost continuously with wastewater, some untreated, from uranium mines upstream.
The river rises on the slopes of the Continental Divide of the Americas a half-mile east of Hosta Butte in McKinley County, New Mexico. It flows first north then west through a wide, barren desert valley bordered by high rocky buttes and cliffs. It intersects Interstate 40 and receives the South Fork Puerco River from the left near Gallup. For most of its remaining course, the interstate and the Atchison, Topeka and Santa Fe Railroad follow the river's valley. The Puerco then crosses into Arizona and passes Houck, Sanders and Chambers, then flows through the middle of Petrified Forest National Park, where Lithodendron Wash enters from the right. The river then flows southwest to its confluence with the Little Colorado River, near Holbrook.
The United States Geological Survey (USGS) operates a Puerco River stream gauge 1 mile (1.6 km) southwest of Chambers, Arizona. The maximum discharge recorded by this gauge between 1971 and 2009 was 17,800 cubic feet per second (500 m3/s) on Sept. 30, 1971, and the minimum discharge was often zero from a drainage basin of 2,156 square miles (5,580 km2).
Radioactive spill 
In one of the worst radioactive spills in U.S. history, on July 16, 1979, a tailings pond at the Church Rock uranium mill owned by United Nuclear Corporation breached its dam, and 93 million gallons (350,000 m3) of radioactive, acidic uranium tailings solution flowed into the North Fork of the Puerco River. Approximately 1,100 short tons (1,000 t) of uranium mine waste contaminated 250 acres (100 ha) of land and up to 50 miles (80 km) of the Puerco River.
See also 
- Petrified Forest National Park
- List of rivers of Arizona
- List of rivers of New Mexico
- Colorado River
- List of tributaries of the Colorado River
- Source elevation derived from Google Earth search using GNIS source coordinates.
- "Puerco River". Geographic Names Information System (GNIS). United States Geological Survey. February 8, 1980. Retrieved May 28, 2010.
- "The National Map". U.S. Geological Survey. Retrieved Feb. 25, 2011.
- Chris Shuey Contaminant Loading on the Puerco River A Historical Overview Southwest Research and Information Center, October 14, 1992
- Gault, Ramona (September 13, 1989title=Navajos inherity a legacy of radiation), In These Times (Chicago)
- ACME Mapper. USGS Topo Maps for United States (Map). Cartography by United States Geological Survey. http://mapper.acme.com/. Retrieved 2010-10-01.
- "Water-Data Report 2009: 09396100 Puerco River near Chambers, AZ" (pdf). United States Geological Survey. Retrieved May 29, 2010.
- Pasternak, Judy (2010). Yellow Dirt: A Poisoned Land and a People Betrayed. Free Press. p. 149. ISBN 1416594825.
- Brendan Giusti, Radiation Spill in Church Rock Still Haunts 30 Years Later, The Daily Times (Farmington, New Mexico), July 16, 2009, Section: Local
- Carl Jensen, Project Censored (U.S.) 20 Years of Censored News Seven Stories Press, July 1, 2003, p. 84, ISBN 1-888363-52-5