Measurement Device Effect on Channel Water Loss

Abstract

Flow measurement devices can cause significant errors in inflowoutflow channel water loss measurements. The device effects, caused by the increased water surface elevation upstream of a device, must be subtracted from measured losses to correctly estimate conveyance water loss. Methods to calculate device effects are given. In channels with small slopes and in which loss rates increase sharply with water surface increases, inflow‐outflow loss measurements should be made in long channel sections with devices which create as little head loss as possible.