Technical Note: Increased Distance Between Galvanic Lead: Copper Pipe Connections Decreases Lead Release

It has recently been proposed that lead contamination of drinking water arising from galvanic corrosion of lead and copper pipe will be minimized if the lead and copper pipes are brought into direct contact when compared to pipe separations of 1 cm to 15 cm and external electrical contact via a grounding strap. A direct, four month test of this hypothesis was conducted with measurement of galvanic current and lead release to water.

The study finds that increased distance between lead and copper pipe, obtained by incorporating an insulating spacer between the pipes, can dramatically reduce the galvanic current and the magnitude of lead release consistent with expectations based on galvanic theory and the plumbing code