Drinking Water Quality and Supply

From source to sink

Where Nanaimo water comes from

A plain-language tour of the lakes, rivers, or wells that feed Nanaimo, the plants that clean the water, and how it reaches kitchen taps. Lab grades for hardness, lead, and pH live on the water quality page.

On the map

Where Nanaimo water lives

Source waters and treatment plants pinned from published utility names. Open a pin below for the full OpenStreetMap view.

Map showing drinking-water locations for Nanaimo

Map data © OpenStreetMap contributors. Pins are approximate for orientation, not legal survey points.

Deep dive for households

Nanaimo drinking water starts as surface water (rivers, lakes, or reservoirs). The named sources on the utility record are South Nanaimo River (Jump Creek Reservoir), South Fork Reservoir. That is the water that eventually reaches kitchen taps after treatment, not a separate bottled brand.

Water is cleaned at South Fork Water Treatment Plant before it enters city pipes. Gravity-fed membrane ultrafiltration plant online since late 2015; screening, flocculation as needed, UV on secondary membranes, chlorine disinfection. Peak capacity about 116 ML/day.

After treatment, water moves through pumps, storage, and underground mains to reach streets and buildings. Jump Lake provides the large active storage; South Fork Dam maintains intake level for twin gravity pipelines to the plant. Treated water feeds Nanaimo, Snuneymuxw First Nation, and Extension via reservoirs, pump stations, and hundreds of kilometres of mains.

One detail that makes Nanaimo water feel local: Much of the watershed is privately managed forest land; the City partners with Mosaic Forest Management to limit access and protect source quality. Summer releases also support Nanaimo River fisheries flows. Lab grades for hardness, lead, and pH sit on the city water quality page; this overview is about the route the water travels.

Where it starts

Surface water

Rivers, lakes, or reservoirs, not underground wells as the main draw.

Research confidence: high

Named source waters

  • South Nanaimo River (Jump Creek Reservoir)
  • South Fork Reservoir

Treatment plants

These are the buildings that filter and disinfect water before it enters city pipes.

  • South Fork Water Treatment Plant

    Gravity-fed membrane ultrafiltration plant online since late 2015; screening, flocculation as needed, UV on secondary membranes, chlorine disinfection. Peak capacity about 116 ML/day.

How it reaches your street

Jump Lake provides the large active storage; South Fork Dam maintains intake level for twin gravity pipelines to the plant. Treated water feeds Nanaimo, Snuneymuxw First Nation, and Extension via reservoirs, pump stations, and hundreds of kilometres of mains.

Nanaimo water quality grades · All city rankings

Source · ECCC / municipal open data (seed). Last updated 2026-07-22. Refreshed on the site's automated schedule.