Incomplete Wastewater Treatment - A Serious Problem in British Columbia

by Curt Kerns, M.S., R.P.Bio., C.F.S.

Incomplete wastewater treatment has become a serious problem in lower British Columbia. Federal shellfish biologists state over 98% of our intertidal waters are closed to shellfish harvests due to pollution for weeks, months, even years on end. Whether it is a municipal plant that is overloaded during storm water runoff or septic fields that cease functioning during our long, wet, cool winters, incompletely treated sewage is detracting from the esthetic quality that is central to the quality of life in “beautiful” British Columbia. Incomplete treatment of wastewater discharged into watercourses that find their way to saltwater and especially direct discharge of untreated sewage into salt water has been implicated as the causal mechanism of red tides by scientists at the Scripps Oceanography Institute in California. Marine bacteria bloom, feeding on the dissolved compounds, thus creating the conditions optimal for the red tide organisms, dinoflagellates, to flourish. The incidences of harmful algae blooms have grown precipitously in the last century. Here in BC, the Straits of Georgia have recently seen harmful blooms in areas never before visited, such as outbreaks in eastern Baynes Sound (located near Courtenay) an area, which used to be free of the toxic blooms. During recent summers, the entire Strait of Georgia was closed to shellfish harvest due to harmful algae blooms.

Qualicum_HAB .. It has been a common practice to install the least costly wastewater treatment systems -- such as primary treatment only (septic tanks), especially in rural areas, throughout North America. A dense, anaerobic (without oxygen) bacterial mat grows eventually plugging soils especially in cold, wet climates. With central treatment plants being economically impractical in low density neighbourhoods (as well as the problem of what to do with the effluent from central plants besides dumping it into lakes, rivers, or marine waters) advanced onsite wastewater treatment is recognized as being the most obvious solution. In a report to the US Congress, the Environmental Protection Agency cites a number of advantages to using decentralized onsite treatment systems: protects public health and the environment, appropriate for low density communities and varying site conditions, and typically much more cost effective than centralized plants. Sewer lines can cost multiples of treatment. Discharge into surface waters carries a high ecological cost, thus making marine resources ever less available than during historical times. Ladysmith harbour, for example, used to be the most productive shell fish harvest area in BC but has been long closed due to pollution.
Harmful Algae Bloom (HAB) Qualicum, BC



“The significant problems we face cannot be solved at the same level of thinking we were at when we created them.” Albert Einstein

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