Prospect Reservoir, 1888 Source unknown, possibly State Library NSW
Built 1882-1888. Located off Reservoir Road, Prospect.
First proposed 1869. Was completed in 1888 with a capacity of 50,000
million litres and at a cost of 2.7 millions pounds. The
first earthfill embankment dam in Australia. Originally built to store
water fed from the dams of the Upper Nepean system via the Upper Canal.
From Prospect the Lower Canal led to a basin at Guildford, from where
water was piped to several reservoirs around the city (see also Boothtown Aqueduct). Water from
Warragamba reached Prospect
Reservoir in 1940. With the commissioning of the Prospect Water
Filtration Plant
in 1996, raw water transferred from Warragamba and the Upper Nepean
dams was sent directly to the treatment facility, by-passing Prospect
Reservoir.
Prospect
Reservoir is historically significant as a
central element of the Sydney water supply system and is Sydney's
largest reservoir. It was an outstanding civil
engineering acheivement feat for its time. The reservoir and now the
treatment plant supplies the lions share of Sydney's water demand.
The dam wall is 2.21 km long. Whilst an earthen-wall dam, the upstream
side is lined with diorite blocks. Originally the reservior served as
the main storage, with the upstream dams being merely weirs for
diverting the water to Prospect. With the construction of Warragamba
Dam in the 1930's became a temporary storage reservoir, to cope with
daily fluctations in the water demand. Prospect ceased operation as a
dam in 1987.
The valve house was completed in 1889 and is still in use. Most of its
inner workings are original. It is an octagonal shaped building about
10 x
6 metres wide designed in the
Victorian Free Classical style. Built of sandstone, its design borrows
elements
from classical architecture, as evidenced by the formal decoration of
the
parapet and lintel.