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What is Liquid Waste?

Liquid waste is also referred to as wastewater, sewage, and stormwater runoff. Anything that is flushed down a toilet, or poured down a sink or drain, or water that falls on roads, becomes liquid waste.


What is Liquid Waste?

Liquid waste is collected by drains which connect to sewers under the roads.

  • Sanitary sewage from sinks, toilets, and other household drains is conveyed to treatment plants to remove pollutants, garbage, and organic materials before being discharged to the Columbia River.
  • Storm sewers, which collect rainwater and other water drained off the roads (like from washing your car) discharge liquid waste into the Columbia River, without treatment.

Most wastewater comes from everyday activities; however, not all waste can be treated by this system. Some businesses and industries produce waste that may contain hazardous materials and should be disposed of through a qualified collection service. Food service establishments (such as restaurants, cafés, and supermarkets) produce waste that may contain fats, oils, grease, and food scraps, which can cause sewer blockages when poured down the drain.

What Liquid Waste Services does Castlegar Currently Provide?

The City owns and operates a dozen lift stations and roughly 75 kilometers of sewer pipe that collects wastewater from properties and sends it to one of Castlegar’s two wastewater treatment plants.

Sewage from the north end of town is conveyed to the lagoons on the north side of the Columbia River, and sewage from the south side is conveyed to the south sewage treatment plant in the woodland park neighbourhood. At the treatment plants, the wastewater is treated and cleaned before being discharged to the Columbia River. This treatment is vital to protect the river ecosystem as well as the broader environment. It also protects public health, fisheries, wildlife habitat, tourism and recreation opportunities.

The Blueberry area does not have sewage collection. Instead, properties rely on on-site septic tanks and dispersal fields. Septage (septic tank sludge) from these properties is managed by the Regional District of Central Kootenay.

Stormwater makes up the second part of liquid waste. This includes liquids that falls on roads, parking areas, roofs, and other surfaces where it runs off. This can include rainwater, but also water from washing vehicles or driveways, or any other liquids that land on roads, intentionally or accidentally, like oil or other spills. In some areas of Castlegar, stormwater is not captured in storm drains but runs off and infiltrates into the soil. In other areas, stormwater is captured by storm drains, which convey the water to the Columbia River without treatment.

Stormwater, septic systems, sewer collection, and treatment are all addressed in a LWMP. Currently, these components making up the City’s sanitary sewer system operate under a permit issued by the BC Ministry of Environment.

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