CAT CLASS: HQ-10781

6-8 in Centrifugal Dewatering Pump

The 6-8 in Centrifugal Dewatering Pump size class is designed for large clean-water transfer applications including reservoir drawdown, hydrostatic testing, and pond transfer. These pumps feature 6-inch discharge ports and flow rates ranging from 370 to 4,500 gpm, positioning them between the 4-6 in models suited for mid-volume dewatering and the 8-12 in class used for industrial-scale water movement. Major manufacturers in this segment include Godwin and Cornell.

265

Models

Brands

Cat classes

Pick a size class — capacity and reach differ across the range.

Key specifications

Specification	Typical range	What it means
Discharge port diameter	6 in (15.2 cm)	Nominal size determining piping compatibility and flow capacity for this class.
Flow rate	370–4,500 gpm	Volume transfer range spanning smaller reservoir work to full-scale hydrostatic testing.
Maximum head	77–237 ft (23.5–72.2 m)	Total dynamic head capacity, with higher-head models suited for elevated discharge or long piping runs.

How to choose

The 6-8 in class is appropriate when clean-water transfer demands exceed 400 gpm or when vertical lift or distance requires sustained pressure beyond smaller centrifugal pumps. Typical applications include draining large tanks, transferring water between reservoirs, or filling/draining for hydrostatic pipe testing. For moderate-volume excavation dewatering or sites with flow requirements under 1,000 gpm and simpler access, the 4-6 in Centrifugal Dewatering Pump offers easier handling and lower power demands. When industrial process water, municipal basin drawdown, or flow rates consistently above 3,000 gpm are required, the 8-12 in Centrifugal Dewatering Pump delivers the necessary capacity.

What this size handles

Drawdown of municipal water storage reservoirs for inspection or maintenance
Hydrostatic testing of large-diameter water or sewer mains
Transfer of water between holding ponds at treatment facilities
Dewatering flooded retention basins after storm events
Filling or draining cooling towers during industrial shutdowns
Emergency water transfer from compromised storage tanks

Safety & operation

Suction and discharge piping must be secured against movement under high flow and pressure conditions
Pump priming and air-release procedures are critical to prevent cavitation and mechanical damage
Engine exhaust and surface temperatures require clearance from combustible materials and site traffic
Automatic shutdown controls protect against low oil pressure, high coolant temperature, and loss of prime

Transport & logistics

Typically mounted on dedicated tandem-axle trailers requiring a 3/4-ton or larger tow vehicle
Trailer-mounted units often include onboard fuel tanks and control panels for self-contained operation
Delivery to site generally requires staging area with firm ground for trailer positioning and hose layout

Power & supply

Diesel-engine-driven models are standard, with fuel consumption proportional to flow rate and head
Some units available with electric motor drives for stationary installations with three-phase power
Onboard fuel capacity typically supports 8–12 hours of continuous operation at rated flow

Frequently asked

What differentiates 6-8 in pumps from smaller centrifugal dewatering models?

The 6-8 in class offers significantly higher flow rates (up to 4,500 gpm) and head capacity (up to 237 ft), making it suitable for large-volume clean-water transfer rather than typical construction site dewatering.

Can this size handle solids or only clean water?

Centrifugal dewatering pumps in this class are designed for clean or lightly contaminated water; solids handling is minimal compared to trash pumps or submersible slurry pumps of similar size.

What determines whether a 6-inch or 8-inch hose is used?

Despite the 6-8 in class designation, discharge port diameter is typically 6 inches; the size range reflects nominal class naming conventions rather than variable port sizes within the band.

Compare popular models

Find by spec →

Normalised to the same units. A dash means the figure was not published.

Model	Flow rate	Max head	Engine power
Cornell 6H-CC	2,750 gpm	237 ft (72.2 m)	-
Cornell 6SP	4,500 gpm	235 ft (71.6 m)	-
Godwin CD180M	2,100 gpm	77 ft (23.5 m)	-
Cornell 6H-F	3,350 gpm	-	-
Godwin CD150S	2,290 gpm	-	-
Godwin NC150	370 gpm	-	-