16 U.S.C. § 821
Section 821 · State laws and water rights unaffected
This is § 27 of the Federal Power Act of 1920
Amended 2 times on record
Applied in 48 court decisions — leading case First Iowa Hydro-Electric Cooperative v. Federal Power Commission (1946)
Most recently applied in Carrington v. City of Tacoma, Department of Public Utilities, Light Division (April 2017)
How often courts cite this section
Court decisions citing this, by year.Markers show enactment, consequential amendments, and circuit splits over this section — watch for a citation surge after a change or a disagreement. The dip in the last several years is a data-coverage gap, not a real trend — our corpus holds fewer opinions from the most recent years, so recent citations are undercounted.
Nothing contained in this chapter shall be construed as affecting or intending to affect or in any way to interfere with the laws of the respective States relating to the control, appropriation, use, or distribution of water used in irrigation or for municipal or other uses, or any vested right acquired therein.