Nanaimo Septic Systems

Updated August 2026

Filing a septic system with Island Health

A septic system in British Columbia is filed, not permitted. An Authorized Person files a Record of Sewerage System with Island Health before construction, then a Letter of Certification within 30 days of completion. The Regional District of Nanaimo requires that filing as a supporting document on a building permit application for any property not connected to a municipal system.

Updated August 2026

The single most common misunderstanding about onsite systems in this province is the word permit. Nobody issues one. The obligation sits with a qualified person who files, certifies and signs — which changes who is accountable, and for what.

A filing is a record of a sewerage system lodged with the health authority by an Authorized Person, rather than a permission granted by that authority.

What that filing sits inside is what a new system involves.

A filing, not a permit

Onsite systems are governed by the Sewerage System Regulation, B.C. Reg. 326/2004, made under the Public Health Act. Under that regulation the work is recorded with the health authority rather than approved by it. The practical consequence is that no official signs off the design before construction, and no inspector arrives to bless the result.

Who is allowed to file

Two categories of Authorized Person exist. A Registered Onsite Wastewater Practitioner, registered with ASTTBC, may file Type 1 and Type 2 systems under 9,100 litres per day. A Professional — an engineer or geoscientist registered with a recognized professional association — may file any type, including Type 3, and higher flows. A property owner may build a system only under the supervision of an Authorized Person.

Who may file which system
Authorized PersonSystem typesFlow limit
Registered Onsite Wastewater Practitioner (ASTTBC)Type 1 and Type 2Under 9,100 L/day
Professional (engineer or geoscientist)Type 1, Type 2 and Type 3Higher flows
Property ownerConstruction only, under supervisionNot applicable

What Island Health does, and what it does not do

Island Health states that it does not approve the sewerage system design, and does not routinely review filing documents for their technical merit. What Island Health checks is that a filing meets minimum submission criteria — that the form is complete, the plans are present, and a scaled site plan is included. Responsibility for whether the system works rests with the Authorized Person who signed it. Anyone buying a property with a filed system should read that sentence twice.

What gets submitted, and when

Before construction: the Record of Sewerage System, plans and specifications, a scaled site plan, and any covenants, easements or hydrogeological reports that apply to the parcel. Within 30 days of finishing construction: a Letter of Certification, an as-built diagram, and a maintenance plan for the system as built. Those three documents are what a future buyer, inspector or lender will ask for, and they are also what a property with an older system frequently does not have.

Published separation distances
DistanceMeasured fromPublished by
30 mA well supplying a domestic water systemProvince of British Columbia
15 mA well, for a holding tankProvince of British Columbia
30 mNatural boundary of tidal and non-tidal waterIsland Health subdivision standards
3 mA parcel boundaryIsland Health subdivision standards
3 mA buildingIsland Health subdivision standards
15 mA breakout pointIsland Health subdivision standards
0.46 m to 1.2 mMinimum soil depth, by soil type, slope and water supplyIsland Health subdivision standards

The 30 m and 15 m well separations are provincial requirements applying to systems filed after 25 June 2010, and may be varied by a professional competent in hydrogeology. The remaining distances are drawn from Island Health's published subdivision standards rather than from the regulation itself. Confirm current figures with the Authorized Person for any specific property.

Where the building permit fits

The septic filing and the building permit are separate processes with separate authorities. The Regional District of Nanaimo's building permit application checklist requires a septic filing accepted by Island Health for any property not connected to a municipal system. In the District of Lantzville the building permit comes from the District instead, while the septic filing still goes to Island Health.

The filing sequence

  1. 1

    Assessment and designan Authorized Person logs the soil, measures the setbacks and designs to what the site supports.

  2. 2

    Record of Sewerage System filedplans, specifications and a scaled site plan lodged with Island Health before excavation.

  3. 3

    Constructionthe system built to the filed design.

  4. 4

    Letter of Certificationfiled within 30 days of completion with an as-built diagram and a maintenance plan.

Filing touches two other things most often — an inspection of an existing system, what the work costs and Lantzville.

Filing is the part of an onsite system that people discover late, usually when selling. To have the filing handled from the start, get a site assessment booked.