For pumps and blowers that run most hours of the year, energy and maintenance usually cost more over the equipment’s life than the price on the bid sheet. Since July 2025, Ontario’s asset management regulation has required municipalities to plan ten years of lifecycle activities, and their costs, for every asset category.
A bid tabulation compares what each supplier will charge to deliver the equipment. For a pump or a blower that runs most hours of the year, that figure is often a small part of what the owner will pay over the equipment’s life. The rest arrives later, as electricity, maintenance and repairs, every year the equipment runs.
The purchase is a capital cost, paid once. Energy and maintenance are operating costs, paid every year. A comparison that looks only at the first can choose the bid that costs the most to own.
What follows sets out how lifecycle cost is defined, why energy can dominate it for pumps and aeration blowers, what Ontario’s asset management regulation now requires of municipalities, and what information makes a fair comparison possible. It is general information, not advice on any particular facility or procurement.
Pump Life Cycle Costs, a guide published by the Hydraulic Institute, Europump and the US Department of Energy, defines the life cycle cost of any piece of equipment as “the total ‘lifetime’ cost to purchase, install, operate, maintain, and dispose of that equipment.” It breaks that total into eight elements:
A price comparison captures the first element, and the second when installation is part of the contract. The rest are largely paid by the owner, over the life of the equipment.
Because those costs arrive at different times, the guide calls it “practicable, and possibly essential” to calculate a present or discounted value of the life cycle cost before comparing alternatives. The calculation needs a handful of financial inputs: present energy prices, the expected annual increase in energy prices, the discount rate, the interest rate, and the expected life of the equipment. Pumping systems, the guide notes, often have a lifespan of 15 to 20 years.
Ontario’s Water and Energy Conservation Guidance Manual for Sewage Works takes the same approach to energy projects. It says the total cost of an energy conservation measure should include a life cycle analysis resulting in a net present value estimation, covering capital, operation and maintenance including energy, labour and chemicals, financing, the savings from lower energy use, and any grants. It also counts the cost of effects on other treatment processes, such as more solids to process when solids separation improves. That cost falls outside any comparison that looks at one piece of equipment in isolation.
The pump guide is direct about where the money goes. “For a majority of facilities, the lifetime energy and/or maintenance costs will dominate the life cycle costs,” it says, and energy “may dominate the LCC, especially if pumps run more than 2000 hours per year.”
A year has 8,760 hours. Equipment that runs around the clock passes the guide’s 2,000-hour mark more than four times over.
Aeration shows the pattern clearly. Ontario’s guidance manual, citing WEF/ASCE (1998), notes that for suspended growth processes, the family that includes activated sludge, the aeration system can account for between 50 and 90 percent of the energy used at a sewage treatment works. Citing Environment Canada (2006), it adds that blower systems and pumping together can account for 80 to 90 percent of a plant’s energy use. Peer-reviewed work puts aeration at 45 to 75 percent of plant energy costs, a figure examined in why aeration dominates a small plant’s energy bill.
For the blowers themselves, Juan Loera of Carollo Engineers, writing in Water Online, put it plainly: at a typical treatment plant, “energy costs represent roughly 75 percent of the total blower life-cycle cost.” The same pattern can hold for the motors that drive them. Citing the Water Environment Federation (2009), the Ontario manual notes that over a 10-year continuous operational period, the energy consumption of a standard efficiency motor can represent 50 times its initial purchase price.
At the scale of a whole plant, a 2022 life cycle costing study of a small packaged integrated fixed-film activated sludge (IFAS) plant, published in Development Engineering, found that operation and maintenance made up 88.1 percent of life cycle cost and construction 11.9 percent. Aeration was the largest single cost, at 48.9 percent. The study was framed around affordability in developing countries, and its shares depend on local prices, so they are not Ontario figures. What it shows is the structure of the result: operation and maintenance, not construction, carried most of the life cycle cost.
A second reason a bid figure can understate the cost is the gap between the design condition and the operating one. The Ontario manual observes that motors are typically sized for the maximum design load, a load that “will not typically be experienced until far in the future.” The US Environmental Protection Agency makes the matching point about efficiency: “Operating efficiency in the field is usually less than the nominal, full-load efficiency identified by the motor manufacturer,” and it names the operating load as one reason.
An efficiency quoted at a single design point does not tell the owner what the equipment will draw at the loads it will actually run at. A lifecycle comparison needs the power at those loads.
Ontario Regulation 588/17, Asset Management Planning for Municipal Infrastructure, was made under the Infrastructure for Jobs and Prosperity Act, 2015 and came into force on 1 January 2018. It was phased in, and a March 2021 amendment extended the deadlines for the second, third and fourth phases by one year.
| Deadline | What municipalities must have |
|---|---|
| 1 July 2019 | A finalized strategic asset management policy |
| 1 July 2022 | An approved asset management plan for core assets, which include water, wastewater and stormwater management systems, identifying current levels of service and the cost of maintaining them |
| 1 July 2024 | The same, for all municipal infrastructure assets |
| 1 July 2025 | A plan for all assets that adds proposed levels of service, the activities required to meet them, and a strategy to fund those activities |
The last phase is the one that matters for equipment decisions. In the province’s summary, the regulation requires municipalities to determine “the lifecycle activities that they need to undertake for each asset category over a 10-year period to provide the proposed levels of service.” The analysis behind those activities must consider “the entire lifecycle and associated costs related to the assets”, risks, and the financial viability of the options considered. The financial component of the lifecycle management and financial strategy must include “the estimated costs of the identified lifecycle activities to achieve the proposed levels of service, and the funding available, for each year of the full 10-year period.”
Since 1 July 2025, Ontario municipalities have been required to plan ten years of lifecycle activities for every asset category, with estimated costs and available funding for each year.
The regulation is about asset management plans, not individual purchases, and it should not be read as a procurement rule. But a plan that has to carry ten years of lifecycle costs for wastewater assets makes the operating cost of equipment visible in a way that a bid tabulation does not.
The province’s sewage works guidance goes further on procurement itself. The manual says “the energy use of new equipment or processes should become a significant factor for consideration in the procurement process,” and recommends developing procurement standards or policies that consider energy efficiency when equipment is replaced.
The pump guide says designs “should be compared on a like-for-like basis”, and gives the example of considering the same process output, or expressing the figures as a cost per unit of output where two options cannot deliver the same volume. The financial side needs the same discipline. If each bidder picks its own electricity price, discount rate and operating hours, the result compares the bidders’ assumptions rather than their equipment. The practical answer is for the owner to set the assumptions and evaluate every bid against the same ones:
The scale is easy to underestimate. One kilowatt of power drawn around the clock is 8,760 kilowatt-hours a year, and 175,200 kilowatt-hours over 20 years, the top of the guide’s 15 to 20 year range for pumping systems, before any discounting. That is the energy difference between two bids whose average draw differs by a single kilowatt. Multiply it by the rate the plant pays and set the result beside the price gap between the bids.
A lifecycle evaluation needs figures that a price-only bid form does not ask for. Requests that make the comparison possible include:
The same arithmetic applies to equipment that is already running. The pump guide says existing systems offer a greater opportunity for savings through lifecycle methods than new ones, for two reasons: “there are at least 20 times as many pump systems in the installed base as are built each year,” and many existing systems have pumps or controls that are not optimized, because the pumping task changes over time.
The Ontario manual gives a local example. The City of St. Thomas re-piped the air distribution system at its water pollution control plant, which resulted in only one blower being used and a payback period of approximately three years.
Ask for the lifecycle figure, not only the price. For pumps and blowers that run most of the year, the purchase price is usually the smaller number, and the guide’s eight elements make a workable checklist for the rest.
Fix the assumptions before the bids arrive. Electricity price, escalation, discount rate, evaluation period and operating profile, set by the owner and applied to every bid.
Ask for power across the operating range, measured at the wire. A single efficiency figure at the design point describes a condition the plant may not see for years.
Connect the purchase to the asset management plan. In Ontario, the plan already has to carry ten years of lifecycle costs for wastewater assets. A bid evaluation that considers only price leaves those costs out of the purchase decision.
Related reading: why aeration dominates a small plant’s energy bill explains where aeration energy goes, and who runs the plant? covers the staffing that every lifecycle plan also has to fund.
Ontario requirements as described by the province · Accurate as at 8 October 2026 · Verify against the current regulation and guidance before acting on it
North Current develops aeration control technology that retrofits into existing wastewater treatment plants, available through licensing. Get in touch to discuss it.
Published for general information. It is not engineering advice and does not address any specific facility.