Gov. John Hickenlooper this week signed into law a bill allowing homeowners and businesses to reuse bathroom sink, shower and other graywater. Rep. Randy Fischer, D-Fort Collins, and Sen. Gail Schwartz, D-Snowmass Village, introduced House Bill 1044. Hickenlooper signed the bill at Colorado State University on Wednesday.

Standing atop the ramparts of China's Great Wall. Snorkeling the Great Barrier Reef in Australia. These are the giants of our collective imagination, the plumes in our travel cap. Though they might seem timeless, many of the world's most treasured sites are in peril, threatened by theft, development, climate change, or unsustainable tourism.

Colorado Mesa University's Water Center teamed up with the Colorado River District to host a State of the Rivers meeting Monday night. One outcomes was a discussion about the yearly draining the Colorado River endures and the possible consequences thereafter.

Last July, Arizona's state water board approved a large new development in Sierra Vista that would pump 3,300 acre feet of groundwater per year -- despite evidence that such pumping could decrease flow in the San Pedro River, one of the West's healthiest desert rivers.

The old saying that "what goes up must come down" doesn't apply to carbon dioxide pollution in the air, which just hit an unnerving milestone. The chief greenhouse gas was measured Thursday at 400 parts per million in Hawaii, a monitoring site that sets the world's benchmark. It's a symbolic mark that scientists and environmentalists have been anticipating for years.

Colorado is moving quickly to develop a state water plan by late 2015, culminating more than a decade of work. “I think it’s exciting for Colorado, when you look at all the work that’s been done,” said Alan Hamel, who represents the Arkansas River basin on the Colorado Water Conservation Board.

The state House Tuesday passed a bipartisan resolution to protect Colorado’s water supply and recognize the benefits irrigated agriculture provides to Colorado. “We want to make sure we protect water, it’s a precious resource,” said Rep. Lori Saine, R-Dacono. “Water is the lifeblood of our state.

New discoveries of the way plants transport important substances across their biological membranes to resist toxic metals and pests, increase salt and drought tolerance, control water loss and store sugar can have profound implications for increasing the supply of food and energy for our rapidly growing global population.

In 1922, the Colorado River Compact was signed to allocate the river’s water between the seven states and Mexico that rely on and share this water. At the time the Compact was signed, the Colorado River delivered an average of 16.5 million AF of water annually to 20 million people. As discussed in the previous article, that average is now down to 13 million AF for a population of approximately 170 million (2010). The following provides the Lower and Upper Basin states 1922 versus 2010 populations: