Recent reporting on Taranaki rivers highlights a familiar pattern. Water testing shows that many popular swimming spots are frequently unsafe due to contamination, yet people continue to enter the water. Councils respond with signage, advising against swimming under certain conditions or at specific sites. That approach is expected, but the outcome suggests a broader issue.
What changes is not the presence of information, but its effect. Signs are installed, updated, and replaced, yet behaviour remains largely unchanged. People continue to swim in known locations despite warnings, particularly on fine days or in familiar places. Taken together, the system provides information, but does not reliably influence decisions at the point of use.
There are similar examples beyond swimming. Jumping from bridges into rivers continues in many locations despite signage and, in some cases, legal restrictions. These activities are often part of local habit or seasonal behaviour, particularly among younger people. The presence of warnings does not necessarily prevent participation. Familiarity, peer influence, and the perception that risk can be managed all play a role.
This shifts the focus from communication to effectiveness. Warning signs assume that individuals will alter behaviour when presented with risk. In practice, that assumption does not always hold. Over time, repeated exposure to warnings can reduce their impact, particularly where the hazard is not immediately visible. Where risk is visible but accepted, warnings can become part of the background rather than a trigger for change.
There is also a question of design. Signs are a passive tool, relying on interpretation and voluntary compliance. Where environmental conditions change rapidly, such as after rainfall or during seasonal shifts, static messaging can struggle to keep pace. This creates a situation where the presence of a warning does not necessarily reflect current conditions in a way that influences behaviour.
The wider pattern is not limited to one region. Across a range of environmental settings, systems increasingly rely on information rather than direct control. Data is collected, thresholds are set, and the public is informed. That may be appropriate, but it places responsibility on individuals to interpret and act on that information, often in real time and with limited context.
The principle is straightforward. A warning that does not change behaviour is not a control, it is information. Where safety depends on response, the effectiveness of that information becomes critical.
This is not about removing access or discouraging use. It is about recognising that safety systems must do more than provide warnings if they are expected to influence behaviour in practice.
I have several thoughts on signs;
1. When I worked and traveled in Rhodesia (1977) this country worked on the principle of the public using common sense.
Places of great natural beauty like the Victoria Falls had a minimum of signs and guard rails clearly placing great value on the view(s)
2. In Canterbury signs on the Selwyn River access points and Lake Ellesmere/Te Waihora are managed by the Selwyn District Council with monitoring done by ECan.
As a result signs appear to be randomly managed.
Good examples were the signs warning of toxic algae with an arrow pointing to green, amber or red. For a long time no one updated the direction of the arrow allowing me to photograph cobwebs and detritus accumulating on these signs as evidence of neglect.
After I pointed this out and it was reported by RNZ, the signs were replaced with new signs indicating “is this lake/river safe to swim”.
I am puzzled by the change unless the Council is now including water borne pathogens such as E. Coli 0157, etc., as well as toxic algae.
As a vet I preferred the toxic algae signs as this is extremely toxic to dogs and has no antidote.
Are the changes simply a cynical response to mask true state of three of the Selwyn District’s favored camping sites?