The creek drains from the drainage basin of the surrounding area and was once part of the channel that separated the island of Point Richmond with the mainland.

[2] The stream is waterway is named after Don Víctor Castro the owner of the area when it was Rancho San Pablo.

[3] Other waste may only be dumped into the creek through a drainage ditch on Castro Street during high intensity rainfall.

[3] The refinery creates 5.6 million US gallons (21,000 m3) per day of byproduct refinery process water, cooling water, storm water and other wastewater which it discharges into Castro Creek, Castro Cove, Wildcat Marsh, and San Pablo Bay.

[3] Castro Cove has become very polluted from 85 years of unbridled discharge of waste waters with PAHs and mercury from the Chevron Oil Refinery and is scheduled to begin cleanup efforts in summer 2007.