California issued the nation's first statewide green building standards this week, which state officials said could reduce the energy use in commercial buildings by 15% and water for landscaping by as much as 50%.

In a statement, Gov. Arnold Schwarzenegger said the code, crafted by the California Building Standards Commission with input from many groups, is "groundbreaking":

"By adopting this first-in-the-nation statewide green building code, California is again leading the way to fight climate change and protect the environment," the Republican governor stated. "These new building standards will ensure that California remains at the forefront of reducing our carbon footprint and conserving valuable natural resources while also protecting our economy."

"The new standards adopted unanimously by California's Building Standards Commission are an important step for moving California's buildings to a higher level of performance," said Rick Fedrizzi, U.S. Green Building Council (USGBC) president and CEO, in a statement. "Buildings are our first, best opportunity to reduce energy use and CO2 emissions, and greening them must be a critical component of any policy approach that aims to fight climate change."

Buildings account for 39% of the energy used in the United States, 71% of electricity use, 12% of potable water, and 39% of greenhouse gas emissions, according to the USGBC.

California already is making state-owned buildings green and energy efficient, but the statewide code will reduce greenhouse gas emissions, improve energy efficiency, and conserve water in all new commercial buildings, officials said. San Francisco and Los Angeles have strict green building codes based on the USGBC's LEED, which also is the standard for construction of public spaces. But many in the construction industry consider the LEED requirements too strict, and they managed to stave off efforts to incorporate them into the statewide code, according to a report in the Los Angeles Times.