What would we do without our cell phones? In case of an emergency they could mean life or death. Emergency officials want you to download the Alert DC app to your phone. They say it will give you all you need to prepare for an emergency and what to do if an emergency happens. It even has a GPS locator that will give you the fastest route out of the city.

“We first recommend that every family have a plan and a kit so you're ready to go and follow instructions,” said Brian Baker, Interim Director DC Homeland Security and Emergency Management Agency.

Those instructions will change based on the emergency. Some involve using the avenues identified and labeled as "evacuation routes."

"We would be able to identify those routes and what are the best routes and coordinate those with our regional partners because we would have to push people out to Maryland or Virginia,” Baker explained.

But for an unplanned disaster like a hazmat emergency he said the agency is weighing whether it is safer to push everyone out of the city or order people to shelter in place. DCHSEMA has identified close to 200 shelters. Those include schools, rec centers, the DC Convention Center—which holds 42,000 people—and the Capital One Arena, with a capacity just over 18,000.

The challenge is to prevent gridlock in a city where the average evening commute is a bear.

“It’s making sure we have good coordination and communication with our counterparts as to when we're going to release people and where,” he said.

Emergency officials urge residents and visitors to download the app, follow them on social media, and have a plan and emergency kit.

They also recommend snapping a cell phone picture of all your medications and important documents. Upload those to a cloud service or Google Drive so they are always handy in case of emergency. Pets also are part of the District’s emergency evacuation plan.