Onsite Sewage System Management

An important function of public health protection is developing policy in waste management and other land-use planning initiatives to minimize, mitigate and/or prevent environmental threats to human health.

An onsite sewage system is usually located on the land where sewage originates. This type of system treats effluent that is not serviced by a larger municipal or regional sewage system.

The Sewerage System Regulation, under the Public Health Act covers holding tanks for sewage effluent or onsite sewage systems that:

  • Process a sewage flow of less than 22,700 litres per day.
  • Serve single-family systems or duplexes.
  • Serve different buildings on a single parcel of land.
  • Serve one or more parcels on strata lots or a shared interest of land.

Types of Sewage Systems

The Sewerage System Regulation lists three types of sewage systems approved for the disposal of wastewater (domestic waste):

  • Type 1: Treatment by a septic tank and dispersal field only.
  • Type 2: Treatment that produces an effluent consistently containing less than 45 mg/L of total suspended solids and having a five-day biochemical oxygen demand of less than 45 mg/L.
  • Type 3: Treatment that produces an effluent consistently containing less than 10 mg/L of total suspended solids and having:    
    • A five-day biochemical oxygen demand of less than 10 mg/L.
    • A median fecal coliform density of less than 400 Colony Forming Units per 100 mL.

Authorized Persons

The Sewerage System Regulation requires an "authorized person" to file information about a sewage system (referred to as “filing”), along with a letter of certification. The letter of certification must be submitted to the health authority within 30 days of completing construction to provide assurances that the plans and specifications are consistent with standard practice. (See Sewerage System Standard Practice Manual.)

An “authorized person” under the Sewerage System Regulation is a registered onsite wastewater practitioner or professional engineer, as outlined and defined in Authorized Persons under the Sewerage System Regulation (PDF, 182KB):

Registered onsite wastewater practitioners are qualified to design and/or construct type 1 and 2 systems only. Professional engineers may design and/or construct type 3 systems, as well.

Certification of Authorized Persons

The Applied Science Technologists and Technicians of BC (ASTTBC) registers practitioners once they have obtained the proper training through an accredited organization. Once registered, practitioners become “authorized persons” under the Sewerage System Regulation. The ASTTBC is also responsible for accrediting the educational programs in B.C. for wastewater practitioners. For more information, visit the Onsite Wastewater Consumer Information Centre (ASTTBC).

Site Investigations

Site investigations of sewage systems may be initiated in cases where systems are suspected to be negatively affecting a drinking water supply (e.g., as a result of system failure) or causing health hazard, as per the Public Health Act (sections 57-61).

In general, these investigations are complaint driven. They are carried out locally by environmental health officers, who are responsible for service delivery in B.C.’s health authorities regarding:

  • Onsite sewage disposal.
  • Health implications of solid and liquid waste disposal.
  • Land use activities and communicable disease.
  • Public health issues concerning subdivision assessment processes

Sewage System Administration Process

See this flowchart (or click on its small image below) for an outline of the process and parties involved in administering the Sewerage System Regulation.