Mahurangi Cement Works (Ruins)
Engineering Site (eg Portland cement works, Maori fortifications)
The Mahurangi Cement Works (near Warkworth) saw New Zealand’s first manufacturing of Portland cement in the 1880s.
The founder of New Zealand’s cement industry, Nathaniel Wilson (1836-1919), emigrated from Glasgow with his family when he was 6 years old. Nathaniel initially trained as a shoemaker, but in 1864 he purchased a small piece of land adjacent to his parents block south of Warkworth village.
Close by, John Southgate had been making lime since 1851 by burning local limestone in a kiln. With limestone deposits on his land Nathaniel decided to give it a go too, building his own lime kiln in 1866. With this he started manufacturing Roche lime, used in plaster and mortar.
New Zealand’s first Portland cement
Nathaniel became interested in Portland cement in 1883 after reading Henry Reid’s book Science and Art of the Manufacture of Portland Cement. It had been recommended to him by friend J A Pond. After many experiments, by 1885 Nathaniel and his brothers, John and James, began trading as J Wilson and Company. Theirs was the first enterprise to commercially manufacture Portland cement in the Southern Hemisphere.
However, early production was challenging because of the variability of the local limestone. This was eventually overcome, with advice from Mr Pond, by adding pipi shells from the Mahurangi River, and later from Clevedon, to increase the lime content. The coke supplied by Auckland Gas Company also caused problems, and for a short period Wilson’s manufactured their own coke using Westport coal.
The company also had to overcome a prejudicial preference by the authorities for imported cement. However, the intensive public works programme at that time dramatically increased the demand for cement, benefitting the Wilsons. Therefore, by 1893 the company had to undertake major additions to their plant by installing additional grinding and boilers for steam to power the kilns.
Expanding to meet demand
The Wilsons also increased production by utilising the latest in overseas technology identified by Nathaniel’s engineer son William during a trip to the United States of America in 1898. As a result, rotary kilns and ball and tube grinding mills were installed. This meant that annual production grew from 1524 tonnes to 7620 tonnes between 1897 and 1902. With further expansion of the works in 1903 the annual production rose to 20,220 tonnes. At this time other companies established cement works at Whangarei Harbour’s Limestone Island and at Milburn near Dunedin. By 1910 180 people were employed at the Mahurangi works and it was the major employer in Warkworth.
The ready availability of Portland cement from the beginning of the 20th century enabled rapid development of durable structures and port facilities, particularly in Auckland. Notable local projects using Wilson’s cement included the Rangitoto Beacon, Grafton Bridge, and Queen’s Wharf, as well as the Rotorua’s Bath House, and Napier’s breakwater.
The end of the Mahurangi works
Although Wilson’s invested heavily in new machinery and processes, by 1918 the company was voluntarily wound up and amalgamated with the New Zealand Portland Cement Company, whose works were at Limestone Island. It was there that most of the cement was then produced, while the Mahurangi works focused on hydrated lime. By 1926 the closure of the works was imminent and machinery was transferred to Portland (near Whangarei) before the Mahurangi works were closed in 1929.
Limestone Island cement
Portland Cement Works
(This text was adapted with permission from Andrew Marriott and John La Roche, ‘The cement works of Northland,’ in John La Roche (ed.), Evolving Auckland: The city’s engineering heritage, Christchurch, Wily Publications, 2011, pp.281-83)
This place has been registered by Heritage New Zealand as a Category 1 historic place (Register no.82):
Cement Works Ruins: Heritage New Zealand Register information (www.heritage.org.nz).
IPENZ “Engineering to 1990” project
This item of New Zealand’s engineering heritage was recognised as part of the IPENZ “Engineering to 1990” project which the Institution organised to help celebrate the country’s sesquicentenary in 1990. A plaque was unveiled to mark the significance of this place as part of the development of the nation.
This place is also a New Zealand Archaeological Association recorded archaeological site.
References and further reading
Margaret McClure. 'Auckland places', Te Ara - the Encyclopedia of New Zealand,
URL: http://www.TeAra.govt.nz/en/auckland-places/1/5 (updated 21 September 2011)
Dave Pearson Architects Ltd, ‘Wilson’s Cement Works, Warkworth, A Conservation Plan for Rodney District Council,’ 2005
Geoffrey Thornton, Cast in Concrete: Concrete construction in New Zealand, 1850 -1939, Auckland, Reed, 1996
Geoffrey Thornton, New Zealand’s Industrial Heritage, Auckland, Reed, 1982
T H Wilson, History and Growth of Wilsons Portland Cement in New Zealand, Whangarei, Calders Design and Print Company Ltd, 1956
Mahurangi, off State Highway 1, 2 kilometres south of Warkworth
The ruins of the cement works can be viewed during daylight hours.
Nature of Engineering
Building and Construction
(Click image to enlarge)
(Click image to enlarge)
Lat: -36.408306 Long: 174.681284