Agricultural run-off is a concern for the Fraser River and its watershed, and can cause short-term, long-term, and cumulative impacts. Agricultural runoff is a non-point source of pollution and can come from various different sources in different locations. The run-off can consist of pesticides, insecticides, fertilisers, and animal manure — and can enter the runoff through atmospheric deposition, irrigation, and crop residues. These biological and chemical substances can be high in nutrients such as nitrogen, phosphorus, pathogens, and a range of other chemical compounds. A rapid growth in agribusiness along the Fraser River has led to increased pesticide and fertiliser use and farm animal intensities, especially in the Lower Fraser Valley.
Rapid urbanisation in the Lower Fraser Valley has also affected the quality of the Fraser River and its tributaries. Increased infrastructure such as transportation routes and traffic has led to increased surface run-off of pollutants such as hydrocarbons and road-building substances. New development pressures metastasize as the vibrant Vancouver region draws more residents and more economic activity. The Greater Vancouver Regional District now houses more than 2.1 million people. It is expected that in the coming 20 years the population will increase by another 50%.
This growth has detrimental consequences on the watershed due to both the development of surfaces, which exacerbates storm water run-off, and combined sewerage outfalls. There are increased demands upon already inadequate sewage treatment infrastructures and increased indiscriminate waste disposal adjacent to and into the Fraser River and its tributaries. All of these issues can result in surface and groundwater contamination and detrimental longer-term impacts on the biodiversity of the Fraser River Basin.
