Waihi Dredging Plant
The Waihi Dredging Plant has considerable cultural heritage significance. It was one of only two sites in the North Island where river dredging occurred. Tailings from gold batteries upstream were dredged from the river and reprocessed with cyanide to recover values still present. Much experimentation occurred at this plant, with the technological advancement of air agitation tanks patented worldwide from this site by C. F. Brown between 1902 to 1904. The plant ceased operation in 1910, when the then owners transferred operations to a very much larger plant at Mill Road, Paeroa.
The Waihi Dredging Plant site is on the true right bank of the Ohinemuri River, upstream of the confluence with the Waitete Stream. Access is via Lawrence Road, off Cornwall Street, Waihi. [The cycleway skirts the site, before the suspension bridge that crosses the Ohinemuri River.]
The visible remains are contained within a reserve set aside by the Hauraki District Council (in 2003), access via the rights of way at the end of Lawrence Rd, Waihi. Unfortunately at least some of the site and curtilage is now in private ownership, and compromised by a dwelling.
The dredging plant remains have been formally recorded as an archaeological site (no. T13/305), and have legal protection under the Historic Places Act (1993). The site also has an "Historic Area" designation pending, under this same Act [completed 2006]. A subsequent, and fuller description of the site and Historic Area may be found on the Historic Places Trust website: http://www.heritage.org.nz/the-list/details/7670.