Many houses in the Bay Area have cold water lines that are in need of replacing. Modern pipe materials for this purpose include copper, plastic, and galvanized steel. When combining copper pipe with galvanized steel the material placement is very important. The normal lifespan of copper pipes is about 50 years, while galvanized steel pipes only last about 10 years. In the first picture, you can see the corrosive build-up of rust in a steel pipe over a span of 30 years. When the rust from a galvanized steel pipe spreads to a copper pipe, corrosion will quickly occur and form a pinhole leak. The bottom picture shows an example of a copper pipe with rust caused by water coming through the galvanized part. We strongly recommend placing copper pipe first in the line before the galvanized section.