http://www.swrcb.ca.gov/rwqcb5/tentative/0708/ilp-wkshp/introduction.pdf[liên kết hỏng] CA EPA State Water Resource Control Board. Various other sources list the river length from 320 to 450 dặm (720 km). Measured by the USGS utilizing the standard 1:24,000 scale quadrangle sources, the river is 375 dặm (604 km) from its mouth in Suison Bay at Broad Slough to the confluence with the Pit River in Lake Shasta. The distance from there to the confluence of the Middle and South Forks of the Sacramento is an additional 72 dặm (116 km) for a total of 447 dặm (719 km). (The slightly longer South Fork adds 11 dặm (18 km) for a grand total of 458 dặm (737 km).) When the 315 dặm (507 km) Pit River is added to the 375 dặm (604 km) Sacramento River length below their confluence, the Sacramento-Pit River system totals 690 dặm (1.110 km), the third longest river enitirely within one state after the Kuskokwim River in Alaska and the Trinity River in Texas.
