| Physical description: | SITE:
The Walka Water Works site's curtilage is roughly diamond shaped, including a hillside zone, footslopes to a U shaped reservoir or dam, with the industrial complex of the water treatment works to the reservoir's north-west.
An isolated stand of an endangered ecological community, Lower Hunter Spotted Gum-Ironbark Forest, has survived in the area because the small catchment around the constructed reservoir lake was bordered for historical civic purposes some 150 years ago and has remained relatively secure in tenure and management since. (spotted gum is Corymbia maculata: ironbark is one of several species of Eucalyptus)(Stuart Read, pers.comm., 30/11/2015). The bush component acts as an island and a stepping stone for fauna within the (largely cleared) Hunter Valley. It has some 300 species of bird recorded on this site alone. Four threatened bird species have been recorded here: Australiasian bittern (Botaurus poiciloptilus)(endangered); black bittern (Ixobrychus flavicollis)(vulnerable); blue-billed duck (Oxyura australis)(vulnerable) and freckled duck (Stictonetta naevosa)(vulnerable). 18 other threatened fauna species including three more bird species, have been recorded within a 10km radius of Walka Water Works since January 2000, although their specific presence at Walka has not been determined (Maitland City Council, 2015).
The group of buildings known as the Walka Waterworks are located within site boundaries north west of the dam.
The buildings and structures of the complex are generally constructed of load bearing brickwork, with trussed roof structures to the main engine houses, and roofed with corrugated iron.
MAIN PUMP HOUSE
A 2 storey polychrome brick structure with walls up to 1 metre thick. It contains a basement approximately 10 metres deep. Six cast iron columns built to support the first floor remain but all other original features have been replaced or obscured by a raised floor, office partitians and a stairway constructed in the 1950s. The first floor retains sufficient fixtures to demonstrate its previous operations. Original sections of flooring remain as do cast iron cross beams, shoes, joists, decorative grills, timber floor joists and the pilaster which carried the overhaul beam crane. A large sandstone block is located within the wall above and below each pair of joists. The original colour scheme is still visible.
BOILER ROOM - attached to the northern end of the main pump house. The roof is double hipped and clad in corrugated iron and has been subject to modifications. Surviving features include the steam header access hole in the southern wall, column capitals, the flue, the access door to the engine room and an unusual configuration of windows beneath relieving arches in the brickwork.
CHIMNEY - polychrome brick standing 36 metres tall. Square base translating through an octagonal section to become a tapering cylinder, terminating in finely corbelled brickwork. A flue leads to the chimney from the centre of the western wall of the boiler room.
EASTERN EXTENSION TO PUMPHOUSE - 1893 - office - original 9 pane windows replaced by 6 pane windows. An extremely unsympathetic entrance and set of stairs have been inserted in the southern wall. Internal amenities installed during the 1950s by the Electricity Commission and plumbing fittings remain.
WESTERN PUMP HOUSE - 1913 - the building abuts the main pumphouse, its form and detail successfully reflecting the original building. The pump house required the bricking in of openings to the main pump house and removal or relocation of the original window joinery. The existing 9 pane windows on the western side of the building are probably the only remaining original windows of the complex. The internal brickwork is rendered and painted but along its eastern side it retains the profile of the exterior of the main pump house. The roof trusses of riveted steel are exposed. The southern wall is constructed of timber and corrugated iron to enable further expansion.
WORKSHOP - A small single storey building north of, and seperate from, the original boiler room. Four cast iron chutes penetrate the northern wall. This wall is a retaining wall built against an embankment which defines the northern boundary of the pumping station complex. This wall is angled with a butressed base and weepholes. Concrete steps adjacent to the east lead to the road above. The building contains fire bricks for use in the Electricity Commission boilers.
BOILER ROOM ADDITION - a lean to roof and western wall of corrugated iron over a timber frame erected between the workshop and boiler room in 1913.
SETTLING TANK - large rectangular tank (220' x 115' x 10') located north west of the pump house complex. The walls are sandstock brick covered with cement render. The floor is concrete. The tank has not been filled and remains largely intact. Several of its associated artefacts and components, including a vertical iron inlet pipe on the eastern side , an outlet and overflow pipes on the southern side and height guage and ladder remain. A steep, centrally located set of concrete steps lead south down an embankment to the filter beds.
FILTER BEDS - Seven beds were constructed in 3 stages. Beds 1-4 were laid out in a grid fashion around a north/south pipe. All were built of sandstone blocks. Beds 2 and 4 have been damamged by the erection of concrete bases for cooling towers associated with the c1950s power station. Beds 1 and 3 have been uncovered and probably remain substantially intact.
Beds 5 and 6 are of different construction, having been added in 1908. They feature off-form concrete walls with pre-cast concrete cappings. Bed 7 was built in 1913 in a similar design to the 1908 beds and is in reasonable condition. The filtration layers of sand, gravel and brick may remain in silt within beds 1,3,5,6 & 7.
CLEARWATER TANK - of brick construction and located below the filter beds. The brick piers of the rim show evidence of the roof line but iron supports for the roof have been removed. The western side features gate piers with brick caps. The intake, outlet and overflow pipes associated with this tank remain in situ.
RESERVOIR - The reservoir edges follow the natural land contours on the northern and western sides and are bounded by an earthern embankment made from material excavated during the construction of the tanks, filter beds and pumping station on the southern and eastern ends. Its internal face is lined with Ravensfield sandstone blocks. A brick byewash(4m x 2m) is located at the southern west extremity of the reservoir. It has an arched, butressed brick face covered with concrete render. The byewash contains a large valve which could be opened to lower or drain the water in the resevoir.
A circular brick structure with an iron trap door is centrally located on the reservoir's north bank and a small valve house is present about 30m fron the eastern wall. A discharge cooling tunnel runs parallel with the northern bank.
CHIEF ENGINEER'S RESIDENCE - 9 room brick cottage. Substantial footings and rubble, a tennis court and an approach road flanked by introduced trees remain.
SECOND ENGINEER'S COTTAGE - footing of the second engineers 6 room brick cottage remain.
MISCELLANEOUS FEATURES -
An extensive system of concrete paved roads, paths and kerbing installed by the Electricity Commission in the 1950s.
Remnants of the planting scheme installed at the site by the Electricity Commission.
A sparse scatter of plantings from the original period of operation, including an avenue of trees near the Chief Engineer's residence.
A substantial railway formation, including cuttings and embankments, runs from the site of the power station along the northern edge of the reservoir and connects to the North Coast railway main line at the western end of the site. Some sections of the railway track remain in situ. A vehicle track follows the railway line.
A cast iron pipe network and a steel pipe network remain.
The steel steps and concrete footings for the fuel air pump house can be seen at the edge of the rail track below filter bed 7 (Godden & Associates, 1986: 7-29). |