One of a series of simple, easy to find, caches at railway stations in and around Tasman.
Welcome aboard the New Zealand Railways service to Gowan Bridge! Last stop Hope, next stop Spring Grove.
Wiaroa Station was opened here in this park on 31 January, 1876, named after the nearby Wairoa River. In July 1877 it was renamed Brightwater. I suspect that the town was renamed due to postal confusion with another town named Wairoa, near Gisborne.
The Wairoa River was prone to flooding. In March of 1904 the Nelson Evening Mail reported that a flood had reached to 6" (150mm) over the counter at Granville's store. As you can imagine, sometimes both the road and rail bridges were effected. On one instance in 1939 a young gent drove across the rail bridge with his tyres overlapping the ends of the sleepers, despite the raging torrent just centimetres below, in order to attend his wedding in Nelson an hour later.
Brightwater was used as a passing station - the train from Glenhope would wait in the siding while the train from Nelson took the main line. Since the trains were stopping here anyway, this was a good place to refuel and so in 1896 a windmill was added to the Brightwater yards to help with pumping water. An identical such windmill still stands in the Belgrove yards further up the line. A new siding was added in the 1940s to cater for a lime pulverising plant built within the rail yard, which produced 50 tons of powdered lime a day. Maybe this was the last straw for some, for a new family to the Brightwater district complained of the cold, slow and dirty conditions provided for their secondary school children. This was supported by the local residents who in 1947 petitioned for a bus service. About August 1948 school trains where replaced by railway buses, that were soon taking 180 workers and school children into Nelson each day. The profits went to New Zealand Railways and not to the Nelson line. The loss of income was significant.
There was also another railway station nearby, Allington, opened a year after Wairoa and closed about February of 1879, to service the Wairoa Military Camp. However in 1881 records show this was at Brightwater, possibly meaning the the camp was near the town, or the camp near the station. My guess is Allington was near Allington Farm, which is a little to the north. If you can advise just where the Allington stop was, I would like to hear from you.
The cache is pretty much bang on the site of the station building. Enjoy!
Many thanks to AngryTweety for letting me use this cache location.

Brightwater, 1920s

Brightwater from the windmill, 1920s.
References:
Nelson Evening Mail, 19 March 1904
Voller, L: "Rails to Nowhere: The History of the Nelson Railway", published by the Nikau Press 1991
O'Donnell, B: "When Nelson had a Railway", published by the Schematics 2005
Scoble, J: "Names and Opening and Closing Dates of Railway Stations", published by the Rail Heritage Trust of New Zealand, 2010.
Many thanks to AngryTweety for making the space available.