After decades of keeping water rates low and deferring maintenance, scores of drinking water systems built around the time of World War II and earlier are in need of replacement, according to an in-depth AP report.

“The costs to rebuild will be staggering. The costs of inaction are already piling up. The challenge is deepened by drought conditions in some regions and government mandates to remove more contaminants.”

The U.S. Environmental Protection Agency projects that it will cost $384 billion over 20 years to maintain the nation's existing drinking water systems, which will require tens of thousands of miles of replacement pipe and thousands of new or renovated plants. The American Water Works Association, an industry-backed group, puts the price even higher — $1 trillion to replace all outdated pipes and meet growth over the next quarter-century.

"The future is getting a little dark for something as basic and fundamental as water," said Adam Krantz of the Water Infrastructure Network, a lobbying group that is fighting cuts to key federal water programs.

More details here.