This paper presents an extension of the Fread method that improves the accuracy associated with the estimation of conveyance factor and energy slope.

K. Lee, M. Muste, “Refinement of the Fread Method for Improved Tracking of Stream Discharges during Unsteady Flows,” American Society of Civil Engineers, DOI: 10.1061/(ASCE)HY.1943-7900.0001280.