If there is any historic site in New Zealand that could be better cared for, it would have to be the Reefton Historic Power Station. This was the first hydro public power generator in the country. You can get there by walking east along the Reefton riverside track to the swingbridge or driving across the river and immediately left down Rosstown Road. The historic site is at the end of the road.
It was a small water-powered station that was abandoned a long time ago. The signs are informative at the site and along the track, but the site itself looked ill-maintained when we visited. There appears to be a proposal to restore power generation at the site, and there were even some modern parts lying there waiting to be deployed. Hopefully, it will happen, and the site will be better cared for.
Fortunately, the walk is pleasant, and the very old-looking swingbridge is a bit of fun(!)