What's Actually Driving Water Rate Increases Right Now

Water bills are going up faster than the general rate of inflation in most parts of the country, and the increases aren't small. Double-digit percentage jumps in a single rate case, once rare, are becoming routine. When I get asked why, the answer people expect is "inflation" or "aging pipes." Both are part of it, but neither explains the size of what's showing up in current rate filings. The bigger story is in the revenue requirement itself, and specifically in three line items that have all moved at once.

The Revenue Requirement Hasn't Changed Shape — It's Just Gotten Heavier

A water utility's revenue requirement is still built the way it's always been built: operating expenses, plus depreciation, plus a return on rate base (or debt service coverage, for a municipal or co-op system), minus other revenue, equals what rates have to recover. Nothing about that formula is new. What's changed is the size of each component landing in the same test year.

Take a mid-sized system serving roughly 40,000 accounts. Five years ago, a typical rate case might have shown 3-4% annual growth in O&M, modest depreciation growth tied to a steady capital program, and debt service that moved in predictable steps as new bonds were issued. Today the same system is more likely to show O&M growth in the 7-9% range — driven by chemicals, power, and labor, all of which have repriced — stacked on top of a capital program that's been accelerated to catch up on deferred pipe and treatment work, plus new debt issued at rates two to three points higher than what rolled off. None of those three pressures is unique. What's unusual is having all three land in the same few years.

Deferred Capital Work Doesn't Get Cheaper by Waiting

This is the part that tends to get lost in the public conversation about rate increases. A lot of systems held capital spending flat for a decade or more, either because rates were politically difficult to raise or because the assets in question — buried pipe, mostly — don't fail visibly until they do. Deferred maintenance on a distribution system doesn't sit still while it waits. Main breaks increase, non-revenue water climbs, and by the time replacement finally gets funded, it's happening at current construction costs on a larger backlog than would have existed if the work had been paced out.

The accounting doesn't change based on how the spending got timed — capitalized project costs still flow through construction work in progress and into depreciable plant in service the same way whether the project was planned five years ago or triggered by an emergency. But the rate case narrative is different. A commission or governing board reviewing a sudden capital acceleration is going to ask why it wasn't smoothed, and the honest answer — "we deferred it as long as we could" — doesn't make the current bill increase land any softer with ratepayers.

Two ways deferred capital shows up in a rate case

Pattern	What it does to the revenue requirement
Steady, planned replacement (2-3% of system annually)	Depreciation and debt service grow in predictable, digestible steps year over year
Deferred, then accelerated replacement	Depreciation and debt service jump in a single test year, often alongside a spike in emergency O&M for main breaks incurred before the capital program caught up

Financing Costs Are Doing More Work Than People Assume

The interest rate environment gets less attention in the public discussion than it deserves. A system refinancing or issuing new revenue bonds today at rates well above what was available in the low-rate years is carrying meaningfully higher debt service on the same principal amount. For a system reliant on a state revolving fund loan program, the below-market rate on that piece of debt still helps, but SRF funds don't cover the whole capital program at most systems, and the taxable or tax-exempt bond piece is pricing at today's market, not five years ago.

This matters for how you explain a rate increase internally and to a board or commission. If two-thirds of a rate increase is driven by capital and financing costs rather than day-to-day operations, that's a materially different story than "operating costs are out of control," and it changes what kind of rate design or phase-in response makes sense.

Where Affordability Programs Actually Fit

Every conversation about rate increases eventually turns to affordability, and that's a legitimate concern — water is not a discretionary purchase. But it's worth being precise about what a low-income rate assistance program can and can't do. It can shift the burden of a given revenue requirement across the customer base, typically funded through a small surcharge on other classes or through general fund support for a municipal system. It cannot reduce the underlying revenue requirement. The capital and O&M costs described above still have to be recovered from somewhere; an assistance program changes who pays what share, not the total.

That distinction matters when you're presenting rate design options. A tiered or seasonal rate structure aimed at both conservation and affordability changes the allocation of a fixed revenue requirement across usage blocks — it's a cost-allocation and rate-design exercise, not a way to reduce total cost recovery. Confusing the two in a public rate hearing is one of the fastest ways to lose credibility with a board.