From the outside, it looks like a faded peachy-pinkish oversized doll’s house — a little bit like Barbie’s 1980s Dunedin holiday home, minus Ken and a hot-tub.
But its diminutive exterior belies its expansive interior and purpose.
The Union St building is officially called SW3 pump house, and is sandwiched between Otago Polytechnic buildings next to Logan Park.
And when you open the front door, it opens into a vast, subterranean world that is larger on the inside than it appears on the outside.
It’s there because Logan Park’s sports fields all sit on reclaimed land, and SW3 has been sucking water out of it for 95 years so sportspeople can play on it without sinking up to their armpits in mud and water.
Historically, Logan Park was an inlet of Otago Harbour, known as Pelichet Bay.
In the 1870s, the bay was closed up when a causeway was built to create the South Island Main Trunk Railway between Dunedin and Port Chalmers.
At that point, the causeway turned the area into a small lake, which was aptly named Lake Logan after the nearby Logan Point, where Blackhead Quarries is now situated.
Then in 1913, the city began filling in the lake to create extra space so it could host the New Zealand and South Seas Exhibition in 1925-26.
Shortly after the exhibition, the area was converted into playing fields and renamed Logan Park, and in 1930, SW3 was built to keep the area dry.
Behind the roller door is a small room, complete with two large 9-inch Tork-class Crompton Parkinson pumps (each able to pump 4500 cubic metres of water per second), several large isolating valves (taps), a series of pressure gauges and a peculiar device on the wall that looks similar to a seismograph — it was used to monitor the water level in the station.
These days, the original pumps and wheels are still used, but everything else is automated and controlled by a large orange power/fuse box on the back wall.
In the corner of the room sits a simple wooden desk containing a book of maintenance history, which began in 1966 and is still used to this day.
The book’s initial entry on February 24, 1966, states: "Glands repacked with Chesterton Blu-Lon, Spouting and Drainpipes cleaned, Plant on floor level cleaned and building swept out" — all written in elegant longhand and signed "Pritchard".
The last entry was just last week.
Staff who maintain the building say it is like "an iceberg", because it is only 10% of the actual size of the structure.
The other 90% lies underground, through a trapdoor in the left of the tiny room.
Deep down there is a series of steel ladders and walkways, and a subterranean network of pipes sucking up the stormwater in the area and sending it out to Otago Harbour.
And behind the building is another, even bigger chamber buried underground to hold water in the event that one of the pumps malfunctions or power is lost to the station.
So that little house in Union St may no longer look as welcoming as it did at the top of this story, but now you know how important this unassuming house is.
