Your Rate Study Is Only as Good as the Cost Allocation Behind It
A rate study gets rejected for one of two reasons. Either the number is wrong, or the number is right and nobody in the room believes it. The second one happens far more often, and it's almost never a communications problem. It's a cost allocation problem that surfaces for the first time in a council meeting instead of six months earlier, when there was still time to fix it.
A rate increase is a claim: this is what it costs to deliver this service, and here's the increase that closes the gap. Every dollar in that claim traces back to a cost allocation plan, the method your organization uses to assign shared costs, administration, fleet, IT, facilities, across the departments and services that use them. If that allocation is built on assumptions nobody's revisited in three years, the rate study inherits every one of those assumptions, and so does every question you get asked to defend it.
Where the allocation usually breaks first
Most cost allocation plans were built once, by someone who's no longer in the building, using a cost driver that made sense at the time. Square footage, headcount, whatever was easiest to measure. Then the organization changes, a department grows, a service gets added, a building gets repurposed, and the allocation base never gets rebuilt to match. You end up with an indirect cost pool that's still being split the old way, quietly overcharging one enterprise fund and undercharging another.
This matters more for a utility than almost anywhere else, because your rate is legally supposed to reflect the actual cost of service. If your cost allocation plan is charging the water fund for a share of IT costs that actually belong to general administration, your rate study is defensible on paper and wrong in substance. A sharp council member, or a ratepayer group with an accountant on retainer, will find that gap faster than your own finance team did.
The difference between allocated and defensible
Allocated means the math adds up. Defensible means you can walk someone through the logic and they agree it's fair. Those aren't the same standard, and a rate study built to the first one keeps failing the second.
A defensible allocation plan documents the cost driver for every shared cost category, and revisits that driver on a schedule, not just when someone complains. It separates direct costs, the ones a service clearly causes, from indirect costs allocated by a reasonable, documented method. And it holds up the same way every year, because the method doesn't change based on which fund needs the number to look better this cycle.
What this looks like in the room
When someone asks why the wastewater rate needs a twelve percent increase and the finance director can walk through the cost allocation methodology by category, cite the driver for each shared cost, and show the trend over three years, that's a different meeting than the one where the answer is "the consultant's study says so." The first version survives a hostile question. The second one invites five more.
Internal controls do real work here too, not the audit-checklist kind, the kind that actually prevents the embarrassing finding. A cost allocation plan needs a clear owner, a documented review cycle, and a paper trail showing when and why a driver changed. That's the COSO framework applied to a rate study instead of a financial statement audit, and most local governments and utilities have never mapped it that way.
Before the next rate study starts
Pull your current cost allocation plan and ask when the drivers were last reviewed, not the last time the numbers were recalculated using the same drivers. If the honest answer is "longer than three years," that's the fix that needs to happen before the next rate study, not during it. A rate study built on a stale allocation plan is asking a council to approve a conclusion without being able to show its work, and that's the version that gets sent back for revision.
If you're heading into a rate study and want a second look at the cost allocation plan underneath it, I'm happy to talk through what that would look like.
