Under what circumstances does resource levelling become necessary?

Question

Sorry for the preamble here - but I think the context is important.

I'm responsible for tracking progress on a project which runs on a NEC3-ECC contract which requires that programmes (implemented in MS-Project at request of client) be regularly submitted to show the latest progress of works and forecast delivery milestones. The MS-Project files run into 1000's of activities split among 30+ schemes of work each following an identical template.

Some tasks within this programme are constrained by the resource levels available, and the remaining tasks can be safely be assumed to have resource ramp to meet requirements at any given time.

Actual question begins here:

My position is that all tasks where resource is limited to a forecasted amount must be resource levelled (i.e. no overallocations and no significant gaps in the work schedule for each resource), otherwise forecasted delivery milestones are unlikely to be accurate. My reasoning is that these tasks have an assumed duration that has been calculated from the the number of meters of construction to be completed within the task divided by the expected productivity of a single gang, therefore any overallocations invalidate the assumed duration of the task. Similarly any unexplained gaps in in the work schedule of each resource also invalidate the programme, as we wouldn't be standing construction teams down without a good reason.

All this said, I have had several co-workers insist that resource levelling isn't necessary for the programmes we submit, with their explanation being that:

• The resource situation is always fluid and as such doesn't need to be modelled accurately in the programme (this is pretty spurious to me, as this is the entire point of setting a status date when updating a programme/project, dates are forecasted beyond this 'line in the sand' given what information is available at the time).

• It's too much work to implement the resource levelling (with my response being that while it is labour intensive to level resource for 100's of tasks alongside all other constraints such as work permits from local authorities, geographic considerations, and build sequence dependencies between schemes in the programme; these programmes simply aren't a worthwhile exercise unless resource constraints have been properly factored in).

Am I correct to assert that resource levelling is necessary in the above scenario? If so, is there any literature out there which I can use to back up my assertion? These co-workers are unlikely to take my word for it.

Sorry for how long winded this was, afraid I can't figure out how to express this more concisely. Any thoughts appreciated.

Answer 1

The act of leveling is to reschedule your work packages so that over utilized resources are reconciled. But it seems your interest is to identify over-utilized resources, which you can see by report. I agree with you for that intent, in that you need to know if the scheduling tool is calculating resources above capacity (by that I mean way above like 150% or so), then you can go fix it. But you don't have to level the schedule. As you identify who is over utilized and you fix that, which could be by adding additional resources or you moving the package yourself or other combinations of interventions.

I agree with your coworkers in that a precise schedule model that represents work with a ton of probability, uncertainty, chaos, performance variability, and about 1,000,000 more random variable is an academic exercise and valid only up to when work starts, and then it's gone. So increasing the labor to get to a high level of precision seems wasteful to me.

Answer 2

Based on the description, resource leveling is crucial for accurately forecasting delivery milestones, especially when limited resources constrain certain tasks. Your co-workers' argument that resource availability is fluid and doesn't need accurate modeling overlooks the importance of realistic scheduling. Without resource leveling, tasks might show overallocation or idle periods, leading to inaccurate project timelines. Moreover, to optimize project timelines and resource use, combining resource leveling with resource smoothing can help manage deadlines while avoiding resource peaks and troughs (see here). This method can align tasks with available resources, account for dependencies, and maintain a balanced workload. "Project Management: A Systems Approach to Planning, Scheduling, and Controlling" by Harold Kerzner, is a great source that covers these topics and supports the need for accurate resource allocation in project scheduling.