Originally built in 1836 by the Vingtaine de la Ville, the pump ceased being used for town water supplies shortly before the Occupation.
Last year, the procureurs of the vingtaine organised a project to upgrade the pump.
Work began on the £2,000 refurbishment programme – covered by the vingtaine’s own funds – in November when the pump was taken to engineers Rylance in Oxford Road, where Phil Guy and Kieron O’Neill carried out the work.
Public Services lowered the height of the wall to the south of the pump to make it more visible from Colomberie.
The informal ceremony to unveil the pump was carried out by the Constable, Simon Crowcroft.
Vingtaine procureur Senator Paul Routier said that it was important to maintain what was a unique historical feature in the town.