"Each year, around a half a million people go whitewater rafting in Colorado, and the industry is a key economic driver in many rural towns. But in recent months, the issue of rafting and who can float through stretches of private property has divided the state."

"It's simply known as 'the wall,' a steel-and-concrete structure costing about $22 million that will be pounded deep into the floor of the Elizabeth River near one of the worst toxic-waste sites in Hampton Roads."

"The Army Corps of Engineers wants to use ash cast off from coal-fired electrical generation to shore up dozens of miles of Mississippi River levees, drawing fire from environmentalists worried that heavy metals from the filler might make their way into the river."

"U.S. EPA Administrator Lisa Jackson on Wednesday declared the entire concrete-lined Los Angeles River channel 'traditional navigable waters,' a designation crucial to applying Clean Water Act protections throughout its 834-square-mile urban watershed."

"Canada, which has a disputed sovereignty claim to the Northwest Passage, will require all larger ships plying the Arctic sea route to register starting on July 1, the government said on Tuesday."

"Billions of dollars of new business and tens of thousands of jobs will flow to four hub cities -- Los Angeles, Chicago, Orlando and Albany, N.Y. -- where plans for major high-speed rail networks are located, according to the U.S. Conference of Mayors."

Transportation Secretary Ray LaHood's announcement that biking and walking would get equal priority in federal funding as automobiles has drawn praise from bikers and brickbats from the conservative National Association of Manufacturers.

President Obama announced Thursday that the Transportation Dept. is awarding $8 billion in economic stimulus funds to develop America's first nationwide program of high-speed intercity passenger rail service.

"The Obama administration is broadening the standards for how the U.S. government funds public transportation projects in order to disburse money quickly and improve the environment."

"China has begun operating what is, by several measures, the world's fastest rail line."

"Communities in cold climates around the USA are changing their approach to snow and ice removal from highways in an effort to reduce potential harm to wildlife and vegetation caused by road salt runoff."

Fuel barges on the Columbia River are having more accidents, although none so far has resulted in a known spill. The Coast Guard refuses to disclose information about the incidents, citing investigations which it has not completed in periods of up to 16 months.

"So many of us have an old bike collecting dust in the garage. More often than not, they end up in the garbage. But ...one group has found a unique way to recycle them."

When the St. Lawrence Seaway was opened 50 years ago, it promised to move the ocean 1,000 miles inland, boost commerce, and light cities. But some think it has been an environmental nightmare.

If you’re thinking about buying a cleaner, more fuel-efficient car, you might think a hybrid is your best option. But some automakers want people to look at an older technology when they’re looking for green cars: the diesel engine. The Environment Report's Julie Grant reports.