Rebuilding or repairing the nation's extensive networks of highways, transit systems, sewers, power lines, levees and other physical assets has been on Congress' to-do list for years, and the country's infrastructure needs are steadily growing more urgent. The American Society of Civil Engineers gives the nation's infrastructure a D+ grade, and many economists worry that crumbling roads and outdated airports are costing consumers and businesses billions of dollars annually in lost time and revenue. In addition, technological innovations, such as self-driving cars, and the intensifying effects of climate change have forced officials to rethink the kinds of infrastructure that communities need to remain vibrant. Both President Trump, a Republican, and Democratic House Speaker Nancy Pelosi have touted the prospects of passing a bipartisan infrastructure bill. But Democrats favor using federal money to pay for projects, while the president has advocated using federal dollars as seed money to leverage state, local and private funds. As a result, policy experts say an infrastructure deal is unlikely to emerge soon.