Island homes drink groundwater. Every figure here is the Province of British Columbia's own — from its aquifer mapping and its GWELLS well registry — shown verbatim and linked to source. The Province maps 4 aquifers beneath Gambier Island's 1,863 land lots, carrying 248 registered wells, 3 of them with provincial water-chemistry data, and 1 provincial observation well recording long-term water levels.
Bedrock — Fractured crystalline bedrock; 4.1 km²; mapped 2001. Beneath 294 of Gambier Island's lots.
Vulnerability Low; productivity Low; demand Moderate; quality concern Isolated.
122 wells on record; 1 artesian.
Sand and Gravel — Confined sand and gravel - glacio-marine; 0.7 km²; mapped 2001. Beneath 225 of Gambier Island's lots.
Vulnerability Moderate; productivity Low; demand Low; quality concern Local.
7 wells on record; 1 water licence.
Bedrock — Fractured crystalline bedrock; 6.2 km²; mapped 2001. Beneath 131 of Gambier Island's lots.
Vulnerability Moderate; productivity Low; demand Low; quality concern Isolated.
15 wells on record; 2 water licences; 1 artesian; 1 wells with provincial water-chemistry data; 1 provincial observation well (#480 Active).
Bedrock — Fractured crystalline bedrock; 10.3 km²; mapped 2003. Beneath 101 of Gambier Island's lots.
Vulnerability High; productivity Moderate; demand Moderate; quality concern Local.
104 wells on record; 2 artesian; 2 wells with provincial water-chemistry data.
The Province classifies each mapped aquifer's intrinsic vulnerability — how easily contamination at the surface could reach the water — as Low, Moderate or High, based on factors like depth to water and what covers the aquifer. A High rating means relatively little natural protection between the surface and the water people draw from. It describes susceptibility, not current contamination. Productivity describes how readily the aquifer yields water; demand describes the level of use. These are the Province's classifications, not ours.
Most Gulf and Northern Gulf island aquifers are fractured rock: water sits in cracks in sedimentary or crystalline bedrock rather than in a porous bed of sand and gravel. Fractured-rock aquifers store comparatively little water and move it unevenly, which is why neighbouring wells on the same island can report very different yields, and why the Province rates most of these aquifers Low productivity.
Aquifer boundaries are a toggleable layer on the island map. This page presents provincial data with explanatory context; it makes no claims about individual wells or properties.