There will be two fireworks events in Western Tokyo Tama area, in Hachioji and in Tachikawa even though there will be one of the most popular fireworks event in the central Tokyo at Sumida river.
If you are living or staying around Western Tokyo area, don't miss these fireworks as both attractions would be great !
Hachioji : about 3,300 fireworks at Daiwa House stadium Hachioji, 7pm-8:30pm
http://www.hachioji-kankokyokai.or.jp/hanabi/ (Japanese only)
Tachikawa : about 5,000 fireworks at Showa Kine Park, 7:20pm-8:20pm
http://www.tbt.gr.jp/hanabi/ (Japanese only)