California Gov. Gavin Newsom's $20 billion Delta tunnel project has cleared a significant hurdle, but it still has major obstacles to overcome. The plan aims to reroute water from the Sacramento River to a reservoir, addressing water supply issues in California. Delta communities oppose the project, fearing it will harm the environment and local farms. Last week, the Delta Stewardship Council voted to require the Department of Water Resources to address two challenges. Newsom hailed the decision as progress, but other obstacles loom. Court rulings have upended financing plans, state regulators have yet to weigh in on critical water rights decisions, and water agencies are still deciding whether the tunnel will be worth the cost.

Millions of people around the world will pause, at least for a moment, to mark Earth Day. The annual event is Wednesday. It was founded by people who hoped to stir activism to clean up and preserve a planet that's now home to some 8 billion humans and trillions of other organisms. Earth Day has its roots in growing concern over pollution in the 1960s. That's when author Rachel Carson's 1962 book "Silent Spring," about the pesticide DDT and its damaging effects on the food chain, hit bestseller lists and raised awareness about nature's delicate balance. A U.S. senator from Wisconsin, Democrat Gaylord Nelson, had the idea that would become the first Earth Day in 1970.