Nebraska's governor urged U.S. President Barack Obama on Wednesday to block TransCanada's planned Keystone oil pipeline from Alberta to the Gulf Coast, saying it could hurt a regional water source. The State Department could issue a presidential permit for the $7 billion project, which would boost U.S. dependence on Canada's controversial oil sands. Momentum for Keystone picked up last week after the department said the project would have only limited impact on the environment. The State Department should deny the permit on the grounds that the line could put the Ogallala Aquifer at risk, the Midwestern state's governor, Dave Heineman,...