OT - frost and mold proofing PVC (slightly rambly)
Bill Houghton, Sebastopol, CA
>Out here on the north coast, we get locally serious frost - meaning down into the low 20s, and before you snow country folk laugh, understand what I mean by "locally serious" (I saw real frost exactly three times growing up in Oakland, a mere 60 miles south). Last Spring, I reworked our irrigation controls to work better, which involved raising them up about 5 feet. So, I now have a vertical supply line, of PVC, that height. This line is common with our house water, and I can't cut it off, since the cutoff valve I installed also feeds two spigots and LOML doesn't want them turned off.
I've drained the water halfway down by cleaning the inline filter, and am considering pouring a cup of dilute bleach into the line, figuring that it will slowly percolate through and cut down on mold buildup over the winter. Any opinions?