According to the results of benthic surveys, the stream is classified as semi-polluted. However, efficiency is lower in winter and higher in summer. That is partly because the riverine concentrations of phosphorus are very low in winter, and partly because biological processes slow in the cold temperatures. Winter runoff in the watershed is overland, over frozen soils or ice and snow. The result is low phosphorus in the river in winter.
Most phosphorus enters the wetlands associated with mineral suspended solids.
These solids settle quickly, and may not freely exchange their phosphorus with the wetland waters. In addition, there is a large biotic cycle of growth, death and decomposition at work, which leaves a residual of organic sedimentary material. The deposition from this cycle exceeds the deposition of incoming river solids by a wide margin. Both processes immobilize phosphorus in these wetlands. During the early years, phosphorus is also tied up in the new biomass associated with these developing ecosystems.