A residential street that backs onto other gardens is watched, informally and constantly, by the people in those houses. A residential street that backs onto a business park is watched by nobody after closing time — the premises behind it are dark, empty and often screened by a fence, a hedge or a stack of pallets. That is a genuinely different situation and it is the defining feature of a good deal of this suburb.
It runs both ways. A workshop or small unit whose rear boundary faces domestic gardens has an approach that no security guard patrols, no camera covers and no colleague walks past. Both sides of that fence are quieter than their occupants assume, which is why security lock upgrades here get recommended for the back of a property far more often than for the front.
The commercial half of Diep River is mostly small operations — workshops, distributors, trade counters, service businesses — running from units with a roller shutter, a personnel door and not much else. For an operation like that a failed lock is not an inconvenience, it stops the day, which is why business lockout calls from this suburb are treated with real urgency.