The agency pleaded guilty in the Portland Magistrates' Court on Monday to failing to ensure persons other than employees were not exposed to risks to their health or safety.
It was fined $100,000 without conviction and ordered to pay $3,639 in costs.
The two men were riding within Narrawong Flora Reserve in November 2018 at an estimated speed of between 70 and 80km/h when they struck two cable barriers that were suspended across a track.
One of the men required surgery after suffering a fractured vertebrae, fractured pelvis and internal injuries.
The other man sustained a broken collarbone, broken arm, fractured wrist and torn cartilage in his ribs.
An investigation found the cable barriers and attached signage were used to define tracks in the reserve that were subject to seasonal road closures between the Queen's Birthday and Melbourne Cup weekends.
The court heard there was no inspection regime in place for the barriers and they had not been removed in line with Parks Victoria's published reopening dates due to a lack of staffing.
WorkSafe Executive Director of Health and Safety Julie Nielsen said it was an important reminder that employers must consider more than just the safety of their workers.
"It's up to all duty holders to ensure that members of the public and other persons are not exposed to health and safety risks on sites they manage and control," Ms Nielsen said.
"This was an obvious hazard that should have been addressed through a safe work procedure and these two men are now dealing with the serious consequences of that inaction."
To manage risks duty holders should:
- Monitor conditions at the workplace under their management and control.
- Maintain good housekeeping, for example through systems for identifying hazards and removing or controlling associated risks.
- Have in place a documented traffic management plan that is regularly reviewed.
- Ensure the risks associated with installing, operating and removing traffic control devices are addressed.
- Provide clear signage for pedestrians and vehicle operators, including speed restrictions, where appropriate.
- Ensure visibility issues are identified and controlled, particularly if lighting is poor.
- Provide employees with appropriate training and supervision.
