Fort Opau

Fort Opau gun emplacement
This defence post operated in World War Two between January 1942 and June 1944. Interestingly, it had been planned well before the War but it was the activity of German raider boats in the Hauraki Gulf in 1940 that suddenly forced the plans to become a reality. Building began in 1941.
This post was part of a sophisticated network of posts including Paekakariki Hill, Cape Terawhiti and Sinclair Head, defending the western Cook Strait. It was decommissioned before the end of the war and superceded by the larger guns of the Wrights Hill Fortress Battery, Karori. Fortunately Fort Opau never saw action other than numerous training exercises.

Vital statistics
Guns: British 6″ Mk VII breach loading guns (ex India) dating back to the first decade of the 1900s 7.6 tonnes each on 45 PIII naval deck mountings, giving an elevation of 20° and a depression of -7°.
Shells: 45 kilograms explosive.
Each emplacement 570 tonnes concrete; pad three metres thick in the centre, two metres thick at the edges.
Radar: CD No 1MKII Radar Direction Finder.

Heavy Battery
To overcome this, and to increase surveillance capability, the post was equipped with radar. Its range across Cook Strait reached Tory Channel and included the Brothers islands and distant Stevens Island. As it was a wooden building, only the concrete base of the antenna mast remains today. It would be the radar operators who directed the gunners, so the radar was staffed 24 hours a day by members of the Women’s Auxiliary Army Corps (WAACs).

Built on 10,000 cubic metres of infill, and designed to be hidden from the sea, this extensive military post could accommodate 117 personnel. In reality it only accommodated half that number of permanent staff, but at times Home Guard units underwent training here as well.
Gunners from 3rd N.Z. Divisional artillery units were also trained here in preparation for action in the Pacific Theatre.
The Women’s Auxiliary Army Corps (WAACs) had separate sleeping quarters, closer to the gun emplacements. The officers‘ quarters were also isolated from the central barracks area.
The Battery was scaled down in September 1943, with only 14 staff keeping the equipment on standby.
This was the status through to June 1944 when the emplacements were dismantled. The radar continued operation for a further four months.
The hut on this site is not an original army hut. In the 1950s it was positioned in this sheltered spot for use by the fencing teams working on the improvements to Makara Farm, after it had been purchased by the Crown for the radio receiving station. The concrete buildings on the hill above are original.

Source: Information Board on site

Daily roster at Port Opau
So, was the job bearable at this bleak, windswept location? Furlough was ten days off each four months. We know they had weekly picture shows including films borrowed from the U.S. Marine Corps, and the occasional well attended dance night for entertainment, but generally it was a typical military routine:

0600 hrs Reveille
0730 hrs Breakfast
0800 hrs Sick Parade
0830-1000 hrs General fatigues and maintenance
1015-1200 hrs Battery manning and gun drill
1215 hrs Lunch
1300 hrs Sick Parade
1315-1445 hrs Maintenance of equipment and constructive work
1500-1630 hrs Maintenance of equipment and constructive work
1715 hrs Diner
1800 hrs Manning Parade
1820 hrs Extra drill Parade
1830 hrs Sick parade
Source: War diary 73rd Heavy Battery N.Z.A.; entry for 9 January 1942