California, Arizona and Nevada released a plan on Monday to significantly reduce their water use from the drought-stricken Colorado River over the next three years. It’s a historic moment for the seven western states and 40 million Americans that depend on the river, which has seen its flows diminished by 20 percent over the past two decades. POLITICO’s Annie Snider breaks down the details of the tentative deal and remaining concerns for the states. Plus, Sen. Tom Carper (D-Del.) announced Monday he will not run for reelection, leaving behind an environmental legacy that’s spanned more than two decades. For more news on energy and the environment, subscribe to Power Switch, our free evening newsletter: https://www.politico.com/power-switch And for even deeper coverage and analysis, read our Morning Energy newsletter by subscribing to POLITICO Pro:  https://subscriber.politicopro.com/newsletter-archive/morning-energy   Annie Snider covers water issues for POLITICO Pro.  Josh Siegel is an energy reporter for POLITICO.  Nirmal Mulaikal is a POLITICO audio host-producer. Jenny Ament is the executive producer of POLITICO’s audio department. Learn more about your ad choices. Visit megaphone.fm/adchoices