Gun Emplacement No.2

The Inland Battery at Point Peron

This gun emplacement sits further inland than the battery positioned on the tip of Point Peron. Unlike its coastal counterpart, this structure has been steadily undermined by severe sand erosion. The shifting dune system beneath it continues to degrade, slowly tilting the brick and concrete structure and widening existing cracks. In some areas, bricks and sections of concrete have already fallen away below, exposing reinforcement and leaving voids beneath the base.

Originally partially embedded within the dune landscape, the emplacement was constructed in a three-quarter circular reinforced-concrete form. The remaining quarter was left open to allow the 155mm gun to traverse and operate freely. Inside, the central reinforced-concrete gun mount remains intact, still supporting its steel pivot mount. From this position, the gun had an approximate 270-degree arc of fire, covering the shipping approaches from south of Rockingham across to the waters west of Garden Island, guarding the entrance to Cockburn Sound and the Fremantle naval approaches.

The battery was equipped with American 155mm GPF guns on Panama mounts, weapons already considered ageing by the time they were installed during World War II. Despite the relatively short operational life of the battery and the absence of direct enemy engagement, the guns were reportedly difficult to operate and maintain. Plans were later made to replace them with two 5.25-inch dual-purpose naval guns, capable of engaging both surface vessels and aircraft. However, by the time the replacement guns reached Fremantle, strategic priorities had shifted. Cockburn Sound was no longer considered a primary wartime naval base and the new guns were never installed.

Structural Decline

Inside the emplacement, the original brick steps that once wrapped around the interior have broken away and no longer form a continuous access path. Sand has accumulated within the circular structure, and vegetation has taken hold. As a result, it is no longer possible to clearly determine where the original floor level sat or whether the surface was finished in concrete. Ongoing exposure to wind, salt-laden air and moisture has accelerated deterioration. Reinforcing steel is now visible in places, contributing to cracking and spalling of the concrete.

The Hocking Heritage Studio report Point Peron “K” Battery Conservation Management Plan (March 2016) specifically recommended that the structure “be secured and stabilised as soon as possible.”

Seven years after the release of that report, no visible stabilisation works has been undertaken. Sadly, this kind of inaction has become a familiar pattern when it comes to heritage-listed military infrastructure. Structures are acknowledged as significant, yet left exposed to gradual and preventable decline.

Ammunition Bunkers

Directly behind the emplacement are two ammunition stores, positioned to the north-east and south-east. These small concrete magazines, like the main gun position, are affected by dune movement and shifting ground levels. While not yet undermined to the same degree as the emplacement itself, cracks have formed in both concrete bases. In places, the floors show signs of displacement, although the walls remain largely intact for now.

Note on the Photographs

While some of the following photographs may appear repetitive, subtle differences in light, shadow and angle often reveal structural changes that are not immediately visible. However, documentation at this stage remains important, particularly where deterioration is ongoing and potentially accelerating.

October 2022

Project Files

I am not an engineer, mathematician or a structural specialist but this is just an idea I’ve been turning over visually and conceptually.

Straightening the structure

The thought was whether it might be possible to identify the primary weight-bearing area toward the rear-centre of the emplacement and carefully remove sand beneath that section to reduce the differential angle, while temporarily supporting the front portion of the structure. The idea is not unlike the way extreme loads are redistributed or lifted incrementally. Even compared, somewhat crudely, to how an elephant is lifted and supported without placing stress on a single point.

In theory, this could reduce the tilt of the structure towards a more horizontal alignment. There would, of course, be a significant risk, perhaps a 50 per cent chance, that failure could occur along the transition between the load-bearing section and the unsupported mass. Even so, such a break may not necessarily represent a catastrophic outcome when compared with the certainty of ongoing deterioration if no action is taken at all.

The professionals may well say this approach would not work and I readily accept that I may be missing critical structural or material considerations. I cannot claim technical certainty, only that the logic makes sense in my head when looking at how the structure currently sits, what is still supported and what has already effectively lost its footing.

How the structure is failing

Based on the visible erosion and the way the structure currently sits within the dune system, the gun emplacement is no longer a single, uniformly supported mass. Instead, it appears to be responding in three distinct ways:

1) Rear (inland) section (primary weight-bearing area)

The rear portion of the emplacement remains partially supported by compacted sand and dune material. This area appears to be carrying a disproportionate share of the remaining weight of the structure. The concentration of cracking near this point suggests that the rear section is now acting as the main bearing area rather than the structure being evenly supported along its base.

2) Central transition area (loss of support)

Moving forward from the rear, there is a noticeable transition where underlying support begins to drop away. Rather than a gradual, uniform settlement, the structure appears to change angle at this point. This suggests the emplacement is beginning to hinge, responding to the loss of sand beneath it rather than simply settling under its own weight.

3) Front (seaward) section (overhanging mass)

The seaward end of the structure appears to have lost most, if not all, of its original bearing support. As a result, this section is effectively overhanging, behaving more like a cantilever than a footing-based structure. This helps explain why cracking, spalling and exposed reinforcing steel are most pronounced toward the front, where the concrete was never designed to carry load in this way.

Taken together, these conditions indicate that failure is already in progress, occurring gradually and unevenly. The structure is no longer failing as a single unit but through progressive loss of support and redistribution of weight toward the remaining sand-bearing areas.

When doing nothing becomes the problem

My image blow attempts to illustrate the severity of the sand erosion and its impact on the emplacement. I’m not someone inclined to sit back and do nothing while sites like this continue to degrade. After years of committees, reports, professional recommendations and well-meaning intentions, the default outcome still seems to be inaction, blamed on funding cycles, bureaucracy and red tape.

Yes, I understand that conservation work takes planning, experience and a great deal of money but it’s difficult to escape the feeling that, in practice, no one is truly accountable for the outcome. Eighty years on, the structure remains recognised, documented and acknowledged, yet still left to fail.

The question remains: at what point does “doing nothing” become the most damaging intervention of all?