Match an industrial water pump to the job by four numbers: flow in GPM, total dynamic head, how much solid material is in the water, and how many hours a day it has to run. Get those four right and a centrifugal, submersible, or trash pump earns its keep. Get one wrong, usually the head number, and a pump that looked fine on the spec sheet moves half the water you expected.
We size industrial water pump orders at the Concord and Barrie counters most days, for everything from a flooded basement to a construction dewatering job pulling water out of a trench all week. Here is how we walk a customer through it, and what actually changes the answer.
What Water Pump Do I Need for My Site?
Start with three questions before you look at a single model. How many gallons per minute do you need to move, how far and how high does the water have to travel, and is the water clean or does it carry dirt, gravel, and debris. Those three answers point you toward one of three industrial water pump families: a centrifugal pump for general clean water transfer, a submersible pump for dewatering and continuous duty in a wet pit, or a trash pump built to pass solids without clogging. The right pump is usually the smallest one that clears your worst-case flow and head with room to spare, not the biggest one on the lot.
Start With Flow: How Many GPM Do You Actually Need
Flow is the easiest number to get and the one most people skip. If you are dewatering a trench, time how fast the water rises when the pump is off, or estimate the inflow from a nearby storm sewer or groundwater seep. If you are draining a pool or a tank, the volume divided by how many hours you have to empty it gives you a target GPM directly. Undersizing on flow is the single most common industrial water pump mistake we see at the counter: a customer buys a pump rated for twice the flow they need on paper, then discovers the real number was never checked against the job.
Total Dynamic Head: The Number Everyone Skips
Total dynamic head, or TDH, is the real resistance the pump has to overcome, and it is almost never just the vertical lift. It is the vertical distance the water climbs, plus friction loss through the hose (longer and narrower hose costs more), plus losses at every elbow and fitting, plus any pressure the discharge end still needs at the far end of the line. A pump rated for 200 GPM at zero head might move a fraction of that once you add 15 metres of hose, two 90 degree bends, and 6 metres of lift. Ignore TDH and the pump you bought on a flow rating alone will underperform on the actual site, every time.
Suction lift matters separately from discharge head. Most engine driven pumps are only rated for a few metres of suction lift before they lose prime, so if the water source sits well below the pump, a submersible unit that sits in the water and pushes the water out is usually the better tool.
Solids Content Decides Trash Duty vs Clear Water
This is the choice that gets skipped most often, and it is the one that burns an impeller fastest. A centrifugal pump built for clean water transfer has tight clearances between the impeller and the housing, which is exactly what a general water transfer pump wants for efficiency. Run that same pump on water carrying sand, gravel, or construction debris and those tight clearances jam or wear out inside a shift.
A trash pump solves this with a wider impeller and housing clearance built to pass solids up to a rated diameter, usually anywhere from 25 to 75 millimetres depending on the model, without clogging. If the water you are moving has visible grit, silt, leaves, or small debris in it, spec a trash pump from the start and save the impeller a centrifugal unit would sacrifice.
Duty Cycle: One Job vs Running All Day, Every Day
An industrial water pump asked to run two hours on a Saturday and one asked to run continuously for three weeks on a job site are not the same purchase, even at identical flow and head. Continuous duty wears bearings, seals, and engines faster, so an industrial water pump built for occasional use will need more frequent service, and possibly a shorter life, if it is run around the clock. For continuous or unattended dewatering, look for a model built for continuous duty and check it daily; an unattended pump still needs eyes on it.
Engine Driven or Electric?
Away from a power source, an engine driven pump is the only practical option, and most contractor-grade units on Ontario job sites run on a small gas engine in the GX class that is common across the industry for its reliability and easy field service. Engine driven pumps are portable, need no power hookup, and are the default for a trench, a remote site, or anywhere a generator is not already running.
Where power is already on site, an electric pump runs quieter, needs no fuel runs, and produces no exhaust, which matters indoors or in an enclosed pit. The tradeoff is that it needs a proper circuit and cannot move if the site loses power, so a lot of contractors simply keep one of each.
Submersible vs Trash vs Centrifugal, at a Glance
Use this table to narrow the field before you start comparing specific models.
| Pump type | Best for | Watch for |
|---|
| Centrifugal | Clean water transfer, irrigation, general site water | Clogs and wears fast on gritty or debris-laden water |
| Submersible | Dewatering, confined sumps, continuous duty, wastewater | Needs to stay submerged, the pumped water cools the motor, cable and cord rated for the duty |
| Trash / specialty | Solids, sludge, construction debris, chemical transfer | Lower efficiency on clean water than a dedicated centrifugal |
Before You Size a Big Pump, Check the Ontario Water Taking Rules
This has nothing to do with the pump itself, and it catches sites out anyway.
In Ontario, a Permit to Take Water is required once a site takes more than 50,000 litres of water a day from the environment.
That threshold, and the rules around it, come from the Ministry of the Environment, Conservation and Parks under the Ontario Water Resources Act and Ontario Regulation 387/04, set out on the ministry’s Permit to Take Water program page.
Run the math before you assume it does not apply. A 3 inch trash pump moving 200 GPM is pushing roughly 750 to 900 litres a minute, depending on whether the rating is US or imperial gallons, so it clears 50,000 litres in about an hour. A job that only runs a pump for part of a shift can still land above the threshold. Some construction dewatering and road work register instead through the Environmental Activity and Sector Registry, which the ministry’s water taking guidance covers separately. Sizing the pump and checking the rule are two different jobs, and it is worth doing both before water starts moving.
The Mistake We See Most at the Counter
Buying on horsepower or pipe size alone, with no flow or head worked out first, is what sends a customer back a second time. A bigger engine does not fix a pump fighting more head than it was ever rated for, and an oversized pump on a small job wastes fuel and wears out early from running away from its efficient operating range.
Bring the job’s numbers, even rough ones, distance to the water, height of the lift, hose length, and whether the water carries solids, and we will match an industrial water pump to those numbers, the way a proper sizing works. We stock centrifugal water pumps, submersible pumps, and trash and specialty pumps from BE Power Equipment, Koshin, and Tsurumi at both counters, and our trash pump comparison guide and engine driven pump comparison go deeper on specific models if you already know which family you need.
What to Bring When You Call for Sizing Help
Getting an industrial water pump order right on the first try usually takes five minutes on the phone, well before anyone has to guess at the counter. Have the vertical lift in metres, the hose length and diameter you plan to run, whether the water is clean or carries solids, and how many hours a day the pump needs to work.
If you already own a pump and it is underperforming, the make, model, and serial number off the tag let us check it against the same flow and head numbers before assuming the unit itself is at fault. Most industrial water pump problems we diagnose over the phone turn out to be a mismatch between the pump and one of those four numbers, with the pump itself fine.
Frequently Asked Questions
What water pump do I need for my site?
Work out your flow in GPM, your total dynamic head including lift, hose friction, and fittings, whether the water carries solids, and how many hours a day the pump has to run. Those four numbers point to a centrifugal, submersible, or trash pump, and the right size is the smallest one that clears your worst-case numbers.
How do I calculate total dynamic head?
Add the vertical lift from the water source to the discharge point, the friction loss through your hose length and diameter, the losses at each elbow or fitting, and any residual pressure you need at the discharge end. Guessing head from vertical lift alone is the most common sizing error we see.
Can I use a centrifugal pump for muddy or gritty water?
Not for long. A centrifugal pump’s tight impeller clearances are built for clean water efficiency, and grit or debris wears or jams them fast. Move to a trash pump once the water carries visible solids.
Do I need a submersible or an engine driven trash pump?
A submersible pump suits continuous duty in a confined wet pit or sump, where it sits below the waterline and pushes water out. An engine driven trash pump suits a site with no power, or where you need to move the pump between locations through the day.
What size suction hose does an industrial water pump need?
Match the hose diameter to the pump inlet size and never step down to a smaller hose, which chokes flow and looks like a failing pump. Keep the suction run as short and straight as possible, since every elbow and every metre of lift costs flow.
How often should an industrial water pump be serviced?
Judge by the water and the duty cycle; a fixed calendar rarely matches the real wear. Continuous duty on gritty water calls for daily checks of the strainer and inlet; occasional duty on clean water can run a season between a full seal and gasket check.
Bring your job’s flow, head, and water condition to either counter and we will match an industrial water pump to the numbers that actually drive performance. Call the Concord counter at (905) 760-1711 or the Barrie counter at (249) 315-4673, or send the details through our contact form and we will confirm the right pump before you drive over.
