[Footnote C: _Journal_, New England Water Works Assoc., Vol. XXII, p.
279.]


Mr. Allen refers to the bored wood pipe laid many years ago in Eastern
cities. The writer's experience indicates that a bored pipe will not
deliver as much water as a planed stave pipe, on account of the greater
interior roughness of the former.

Referring to the profile, the 8-1/2-in. pipe between Corona and Duran
had a theoretical capacity of 744,000 gal. per day. A recent test showed
it to be delivering water at the rate of 759,000 gal. per day.

The 3-1/2-in. pipe between Vaughn and Pastura had a theoretical capacity
of 84 000 gal. per day. It delivers only 65,000 gal. per day. There are
5 miles of bored pipe on the upper end of this section. Pressure
gaugings show a hydraulic gradient in excess of the theoretical on the
bored pipe, whereas the stave pipe on the lower end carries the 65,000
gal. on a flatter gradient than the theoretical one.

Experience on this pipe line indicates that _n_ = 0.009, in Kutter's
formula, closely approximates the capacity of planed wood stave pipes of
8 to 16 in. in diameter. The writer favors the use of 0.01 as
conservative and economical.

With equal exposure to corrosion, the round band is undoubtedly the
better, but the flat band has the advantage of being completely buried
in the protective coat of the particular kind of wood pipe under
consideration.