Trail Erosion Data and a Maintenance Grant
A parks manager has one grant of $40 000 to spend on a popular day-walk trail that receives about 60 000 visits per year. Monitoring over two seasons shows: a 300 m section on a 15 percent gradient has lost 25 cm of topsoil and widened from 1.2 m to 2.4 m; a 200 m section on flat ground near the car park has muddy patches that persist after rain; and a 150 m section along a creek has a small undercut bank where visitors have cut a shortcut. Visitor surveys show most users are families doing a 90-minute return walk. Two options are costed: hardening the steep section with stone steps and drainage ($34 000), or boardwalking the muddy flat section plus a fence at the creek shortcut ($28 000).
1. Recommend how the manager should allocate the grant, justifying the choice with the monitoring data and the visitor profile.
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The strongest recommendation is to fund the steep-section hardening ($34 000) and use the remaining $6 000 for signage and a temporary fence at the creek shortcut.
Why the steep section first. It shows the clearest evidence of active, accelerating damage: 25 cm of topsoil lost and doubling of trail width. Widening means visitors are already avoiding the damaged tread, which spreads impact sideways. On a 15 percent gradient, water concentrates and erosion compounds each season, so delay raises future cost. This is the section where intervention changes the trajectory.
Why not the flat section first. The muddy flat section is unpleasant but stable; mud that persists after rain is a comfort and minor-safety issue, not a progressive loss of soil. It can be addressed in a later grant cycle.
Why the visitor profile matters. Families on a 90-minute walk will use the steep section too, and an eroded, widening tread on a gradient is a slip and trip hazard for children. Hardening improves both durability and safety for the dominant user group.
Why the creek shortcut still needs action. An undercut bank is a safety risk even if small, and $6 000 buys signage and a temporary barrier while the main works proceed. Leaving it entirely unaddressed would be hard to defend.
2. A volunteer group offers to boardwalk the muddy flat section for free if the manager supplies materials costing $9 000. Explain how this changes the allocation and what risk the manager must weigh.
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The offer changes the arithmetic substantially. The manager can now fund the steep section ($34 000) and the volunteer materials ($9 000), totalling $43 000 - which exceeds the grant by $3 000. Options are to seek a small top-up, defer some signage, or negotiate materials down.
If the $3 000 can be found, the manager addresses both the progressive erosion and the persistent mud in one season, which is better value than either alone.
The risk to weigh is quality control and liability. Volunteer-built boardwalk on a high-traffic family trail must meet the parks service's construction standard, or it becomes a maintenance burden and a safety hazard. The manager must confirm the volunteers are supervised by someone with relevant experience, that the design is approved before work starts, and that the structure is inspected on completion. Free labour is only a saving if the result is durable; a failing boardwalk within two years would cost more than the original $28 000 option.