Sacrifical anodes protect the exterior of the pipe by arresting future corrosion. Anodes are strategically located to target vulnerable corrosion zones, extending the pipe's service life for decades.
Cathodic protection uses zinc or magnesium anodes to protect pipe exterior as per AWWA M27 manual. Anodes are accurately located above the pipe using hydro excavation and results from the RFEC and video evaluation. The anode lead (wire) is welded to the exterior of the pipe, the anode is placed in the ground and then covered over. Locations of each anode is saved for future reference.
The anodes can protect the pipe exterior from corrosion for up to 20 years and can be simply replaced once depleted.