Campbellton draws municipal drinking water from Prichard Lake - Smith Lake Watershed (protected public surface supply in Sugarloaf Provincial Park area), treated at Campbellton municipal water treatment / distribution system.
Ask where Campbellton drinking water begins and the answer is Prichard Lake - Smith Lake Watershed (protected public surface supply in Sugarloaf Provincial Park area), then Campbellton municipal water treatment / distribution system. That supply chain is what the water atlas puts beside hardness and lead.
City operates the public supply serving Campbellton, Atholville, and Tide Head zones under NB Clean Water Act monitoring. Exact process train (filtration/disinfection detail) is not published in open municipal docs; source protection is via provincial Watershed Protected Area Designation Order.
See the Campbellton water page for the grade, source notes, and municipal report links.