In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Q: More than half of the rivers and streams in the U.S. are in poor biological health, unable to support healthy populations of aquatic insects and other creatures, according to a new nationwide survey released Tuesday. 
  
 The Environmental Protection Agency sampled nearly 2,000 locations in 2008 and 2009 _ from rivers as large as the Mississippi River to streams small enough for wading. The study found more than 55 percent of them in poor condition, 23 percent in fair shape, and 21 percent in good biological health. 
  
 The most widespread problem was high levels of nutrient pollution, caused by phosphorus and nitrogen washing into rivers and streams from farms, cities, and sewers. High levels of phosphorus _ a common ingredient in detergents and fertilizers _ were found in 40 percent of rivers and streams. Another problem detected was development. Land clearing and building along waterways increases erosion and flooding, and allows more pollutants to enter waters. 
  
 "This new science shows that America's streams and rivers are under significant pressure," said Nancy Stoner, acting assistant administrator of EPA's water office. "We must continue to invest in protecting and restoring our nation's streams and rivers as they are vital sources of our drinking water, provide many recreational opportunities, and play a critical role in the economy." 
  
 Conditions are worse in the East, the report found. More than 70 percent of streams and rivers from the Texas coast to the New Jersey coast are in poor shape. Streams and rivers are healthiest in Western mountain areas, where only 26 percent were classified as in poor condition. 
  
 The EPA also found some potential risks for human health. In 9 percent of rivers and streams, bacteria exceeded thresholds protective of human health. And mercury, which is toxic, was found in fish tissue along 13,000 miles (21,000 kilometers) of streams at levels exceeding health-based standards. Mercury, which is naturally occurring, also can enter the environment from coal-burning power plants and from burning hazardous wastes. The Obama administration finalized regulations to control mercury pollution from coal-burning power plants for the first time in late 2011. 
  
 ___ 
  
 Follow Dina Cappiello's environment coverage on Twitter (at)dinacappiello ||||| The news from a comprehensive national survey of river and stream health is not good: Only about a fifth of the length of America’s rivers and streams is in good biological condition, while 55% is in poor shape. 
  
 The survey, which analyzed water samples taken in the summers of 2008 and 2009 at more than 1,900 randomly selected sites, was coordinated by the U.S. Environmental Protection Agency. 
  
 The results, released Tuesday, found that of the three climatic regions discussed in the report, the West -- with its large swaths of undeveloped land -- was in the best shape: 42% of its river and stream length was in good ecological condition, 27% in fair condition and 30% in poor condition. 
  
 In the eastern highlands, 63% of river and stream miles were in poor shape, while in the Plains and lowlands regions (roughly the country’s midsection and much of the South), 58% fell into that category. 
  
 Excessive nitrogen and phosphorus levels, sedimentation and denuded riverbanks were among the leading problems. Unsafe bacteria levels were found in 9% of river and stream miles, and potentially unsafe levels of mercury were detected in fish in more than 13,000 miles of rivers across the country. |||||
A: 
America's millions of miles of rivers and streams are in terrible shape, an extensive Environmental Protection Agency survey has found. After sampling close to 2,000 locations ranging from the Mississippi to tiny streams, the EPA found that just a fifth of rivers and streams are in good enough biological shape to support healthy populations of aquatic life, the AP reports. Some 23% were classed as fair and a shocking 55% were considered poor. Excessive nitrogen and phosphorus levels were among the biggest problems found, with conditions worse in the East than the West, the Los Angeles Times reports. Only 26% of rivers and streams were classed as poor in Western mountain areas, while 70% of rivers and streams from the Texas coast to New Jersey were in poor condition. "We must continue to invest in protecting and restoring our nation's streams and rivers as they are vital sources of our drinking water, provide many recreational opportunities, and play a critical role in the economy," an EPA spokeswoman says.