The city of Alexandria and Arlington County took steps toward an efficient and sustainable future this week by adopting plans and policies that will drastically reduce greenhouse gas emissions in the future.

Alexandria City Council said it will try to reduce carbon emissions by 80 percent in 40 years as part of the Energy and Climate Change Action Plan adopted at Saturday’s meeting. The city’s plan, which grew out of the Eco-City Charter, combines Alexandria policies on environmentally sustainable transportation, urban forestry and building codes, among others, under one umbrella document.

“It is not a big, new policy document,” said William Skrabak, the city’s director of the Office of Environmental Quality. “It basically tries to quantify and take into consideration what we’ve already adopted in our environmental action plan.”

Vehicles, commercial and residential buildings are responsible for the majority of the 2.2 million metric tons of greenhouse gas emissions that were emitted from Alexandria in 2005, Skrabak said. That breaks down to 16 metric tons of carbon dioxide equivalent emissions per capita. The city is using the 2005 data as its baseline for future measurements.

The first benchmark will be to reduce emissions by 10 percent in 2012 to equal 2005 levels, Skrabak said.

“I think the city government is getting close to the 2012 target, but on a community-wide basis, we don’t think we are there yet,” he said, adding that the city is using federal grant money to educate residents and business owners.

The city also has planned $6.5 million to address flooding along the waterfront and is working on several public transit initiatives. Projects such as another emissions inventory and flood controls would continue to go before the council for budget approval, Skrabak said.

The Arlington County Board is expected to pass its Community Energy Plan on Tuesday night. That plan aims to reduce greenhouse gas emissions by about 70 percent by 2050.

“It is the next chapter in Arlington’s sustainability story,” said Jay Fisette (D), an Arlington County Board member who led a task force to develop the energy plan. “We started this story 40 years ago with the advent of Metro . . . We’ve been . . . refining it for 30 years.”

Following the vote, County Manager Barbara Donnellan, her staff and a task force will use the plan as a framework to develop an implementation process over the next 18 months.

Commercial and residential buildings and traffic also made up most of Arlington’s 2.73 million metric tons of greenhouse gas emissions in 2007. That is the year Arlington will use as its baseline. The county totaled 13.4 metric tons of carbon dioxide equivalents per capita in 2007. The goal is to reach at least 3 metric tons per person by 2050 using a combination of energy efficiencies, solar power and a network of localized energy generation called district energy, Fisette said.