ISBN: 1 84057 843 2
Published Date: 07/10/2017
Wastewater treatment works represent an important contributor to the phosphorus load in waterbodies. Analysis of data collected for the Chemical Investigations Programme indicated that metal dosing for phosphorus reduction has a significant impact on the relative proportions of Soluble Reactive Phosphorus (SRP) and Total Phosphorus (TP) in effluent. Where dosing is applied the SRP/TP ratio can be as low as 30%, but can also be highly variable.
Analysis of field data from 10 catchments collected for this study indicated that phosphorus speciation in rivers is not the same throughout the catchment or throughout the year. The assumption that all reactive phosphorus is soluble is incorrect for areas with elevated iron, while higher in-river suspended solids levels lead to lower SRP/TP.
It is recommended that a clearly defined methodology for the determination of phosphorus in effluent and surface waters is established, and the link between SRP and biota is explored further.