This Western Diamondback rattlesnake (crotelus atrox) was recently killed at a water treatment facility between Diamond Bar and Chino Hills.
This "freak of nature" measured 9 feet 1 inch long and weighed a hefty 97 pounds. "Normally" rattlesnakes of this species grow to 7 feet.
Something in the water? Doubt it. However, with a water source nearby I am sure this rattlesnake had plenty of vermin to feast on.