Approximately 9,000 fireworks will be launched from the river banks of the Tama River. The opening ceremony will be at 5pm with 60-minutes of fireworks from 5:30pm. See here for a detailed map of the area (Japanese only).
Event details are taken from official sources whenever possible. It is always prudent to check the official event website before attending to make sure that there have not been any changes. If you know of an error in the calendar, then please let me know through the contact form.