Waterbury Fire was called for a possible structure fire at an apartment complex at 21 Eastern Ave, they arrived to find heavy fire showing from the second floor rear of Building #2 in the complex. With the only hydrant was at the entrance of the complex and approximately 500 ft large diameter supply line was layed into the complex. The crews made quick work of making sure the building was evacuated and containing the fire to the unit of origin. Truck 1 opened the roof for ventilation and to confirm that the fire had not spread to any other units through the attic space. The quick actions brought the fire undercontrol in about 15 minute but crews would remain on scene for an extended period of time for overhaul and to assist the fire marshal in the investigation of the fire.