Prompted by the economies in fuel consumption available
from the use of diesel engines, Southampton Corporation installed three
Ruston and Hornsby diesel engines in the 1930’s and sank a new well
for the new diesel driven well pump, in a position to the South of the steam
engines.
A further wing of the building was constructed in 1934 and still accommodates
the 3 cylinder engine for the well pump and a 4 cylinder engine driving a two
stage centrifugal pump for the high lift duty, pumping up to the service reservoir
on the downs.
The third Ruston engine was installed in the wooden
hut near the main gate, and its duty was to pump water to the additional
head required to reach the service reservoir on high ground at Yew hill to
the south of Winchester. The efficiency and convenience of the diesel engines
led increasingly to their use in preference to steam and from 1937 onwards,
the steam plant was relegated to standby duty.
