Floodplains, streams and wetlands (i.e. freshwater ecosystems) are generally important locations for the nutrient uptake that is controlled by biotic and abiotic mechanisms. Research on lake and stream processes has repeatedly attributed the major loss of phosphorus (P) from the water column to settling of particles onto the sediments. In this work, the phosphorus retention efficiency is measured using short-term addition and tracer injections to estimate nutrient uptake coefficient (k). A conservative tracer (Br) and the Soluble Reactive Phosphorus (SRP) were co-injected into the canal. Water flow in channels is turbulent and the dissolved chemicals are usually well-mixed in the water column with transport properties following closely the flow variations. Therefore, a model for transient depth averaged free surface flow with solute transport, involving a depth averaged k-ε turbulence model will be applied. There is a mutual benefit between the experimental and computational activity which can be used to obtain dispersion and uptake rates in the canal under the assumed conditions.