A citywide power outage, a small plane crashing into a 40-story apartment building and a fire at the Deutsche Bank building were all events that left New Yorkers anxious over what was going on and how to react. To make sure residents are getting important information during an emergency, New York City is testing a new notification system in four pilot communities. The six-month trial, called Notify NYC, delivers alerts by text messages, e-mail and phone calls. The first of its kind in New York City, the pilot will send notifications about water main breaks, approaching storms, construction accidents and other minor events, and alerts that tell residents what to do in case of emergencies such as chemical spills, blackouts and severe flooding. The trial, which began in December and costs $750,000, selected each pilot community for its own unique challenges: southwest Staten Island for its industrial facilities, for example, and Queens for its susceptibility to flooding. To participate, volunteers can log on to the pilot's Web site and provide a name, e-mail address and cell phone number.