Dewatering Pump CDW High Head
Details as follows:
Low Head
NA
Medium Head
NA
High Head
2000-3500 LPM
All dewatering pumps, including Cosmos Pumps’ dewatering pumps, must function efficiently regardless of the application or purpose. The Drainage Pumps are part of our extensive selection of dewatering pumps.
Pumps for drainage may handle a variety of water conditions, including semisolid, clean, and packed with thick but minute particulates. These pumps are helpful for raw water, groundwater, general dewatering, and construction sites.
Dewatering Pump HP Selection — CDW Range (1.5 HP to 50 HP)
The CDW submersible dewatering pump range spans 1.5 HP to 75 HP across three model tiers — CDW Standard, CDW High Head, and CDW Ultra High Head. Each tier optimises for a different duty: the Standard delivers high flow at moderate head, the High Head trades flow volume for maximum lift, and the Ultra High Head handles shaft depths to 200 M. Use the selector table below to identify the right HP and model for your project.
CDW Dewatering Pump HP Selector Table
Typical indicative performance based on CDW product range specifications. All values marked with ¹ are subject to confirmation against model-specific pump curves — request from Cosmos team before final specification.
| Motor HP | Rated Power | CDW Standard: Max Flow (LPM)¹ | CDW Standard: Shut-Off Head (M)¹ | CDW High Head: Max Flow (LPM)¹ | CDW High Head: Shut-Off Head (M)¹ | Select High Head When |
|---|---|---|---|---|---|---|
| 1.5 HP | 1.1 kW | ~500–800 | ~25–30 | — | — | (CDW Standard only at this HP) |
| 2 HP | 1.5 kW | ~700–1,100 | ~28–35 | — | — | (CDW Standard only at this HP) |
| 3 HP | 2.2 kW | ~1,000–1,500 | ~32–42 | — | — | (CDW Standard only at this HP) |
| 5 HP | 3.7 kW | ~1,500–2,200 | ~42–52 | ~350–500 | ~52–65 | Discharge run >100 M or site depth >6 M |
| 7.5 HP | 5.5 kW | ~2,200–3,000 | ~48–62 | ~450–650 | ~65–82 | TDH >55 M (long runs or deeper sumps) |
| 10 HP | 7.5 kW | ~3,000–3,800 | ~55–70 | ~600–900 | ~80–95 | Tunnels, adits, or discharge >200 M |
| 15 HP | 11 kW | ~4,000–5,000 | ~65–75 | ~800–1,200 | ~95–110 | Mine shafts 20–35 M or metro tunnels |
| 20 HP | 15 kW | ~5,000–6,000 | ~70–80 | ~1,000–1,500 | ~105–120 | Deep tunnel drainage, long mine runs |
| 30 HP | 22 kW | ~6,500–7,500 | ~75–84 | ~1,300–1,800 | ~115–130 | Mine shafts 35–55 M, hydro project sumps |
| 40 HP | 30 kW | ~7,500–8,000 | ~80–85 | ~1,600–2,000 | ~125–135 | Underground rail or mine drainage |
| 50 HP | 37 kW | ~8,000–8,500 | ~83–86.5 | ~1,900–2,200 | ~135–140 | Where TDH approaches 140 M |
CDW Ultra High Head (50–120 HP): Where total dynamic head exceeds 90 M, the CDW Ultra High Head is the required specification — shut-off head up to 200 M, flow 50–200 m³/h. Learn more about the CDW Ultra High Head →
How to Choose the Right HP Dewatering Pump
1. Calculate Total Dynamic Head (TDH) First
Total dynamic head is the sum of static lift (vertical distance from sump to discharge point) plus friction losses in the discharge pipe. Under-specifying TDH is the most common pump selection error on construction sites — a pump rated at 50 M shut-off head may only deliver 30 M of usable flow head at the operating point.
Practical TDH guide: Per BIS IS 9137 (Indian Standard for submersible pump testing), pumps must be selected for duty-point TDH, not shut-off head. For a 75 mm (3″) discharge hose at 1,000–1,500 LPM, friction loss is approximately 5–8 M per 100 M of pipe. A 200 M discharge run at this flow adds 10–16 M to the TDH — this alone can push a CDW Standard requirement into CDW High Head territory.
2. Match HP to Required Flow Volume
Flow volume determines how fast a sump can be emptied. Where dewatering time is critical — monsoon flood control, large basement pits during peak inflow, multi-sump EPC sites — prioritise the CDW Standard for its higher LPM output at the same HP. Where head is the constraint and flow can be managed with longer run time, the CDW High Head is the correct choice.
3. Factor Discharge Distance Into HP Sizing
Horizontal discharge distance adds friction head to the TDH, effectively increasing the HP requirement. A 5 HP CDW Standard pump (max head ~52 M) covering 30 M of static lift is adequate for a trench 3–4 M deep. But add a 250 M horizontal discharge run and TDH climbs above 52 M — requiring a CDW High Head 5 HP or an upgrade to 7.5 HP CDW Standard.
Site Condition Quick Reference
| Site Type | Depth | Inflow Rate | Discharge Distance | HP Range | Recommended Model |
|---|---|---|---|---|---|
| Road / utility trench | 1–3 M | Low (seasonal seepage) | Up to 50 M | 1.5–3 HP | CDW Standard |
| Building basement | 3–6 M | Moderate (monsoon groundwater) | Up to 100 M | 3–7.5 HP | CDW Standard |
| Foundation pit | 5–10 M | Moderate to high | Up to 200 M | 7.5–15 HP | CDW Standard or CDW High Head |
| Metro / highway tunnel | 10–30 M | High (continuous inflow) | Up to 400 M | 15–40 HP | CDW High Head |
| Open pit mine / adit | 20–60 M | Very high | Up to 500 M | 30–50 HP | CDW High Head |
| Underground mine shaft | >60 M | Very high | >500 M | 50 HP+ | CDW Ultra High Head |
For a complete guide to open pit mine dewatering and underground mine drainage applications — including CDW High Head specifications, case studies, and project references — visit the Cosmos mining sector page.
Frequently Asked Questions — Dewatering Pump HP Selection
What HP dewatering pump do I need for a construction trench?
For a road or utility trench 2–4 metres deep under typical alluvial groundwater conditions, a 3 HP CDW Standard is the baseline specification. For a deeper trench (4–8 M) or high groundwater inflow (heavy monsoon seepage or sandy/gravelly soil), upsize to 5–7.5 HP CDW Standard. If the discharge pipe runs more than 150 M from the trench, calculate the total dynamic head — friction losses may push the requirement into CDW High Head territory even at 5 HP.
What is the flow rate of a 5 HP dewatering pump?
A 5 HP CDW Standard submersible dewatering pump delivers approximately 1,500–2,200 LPM at 10 M head under indicative rated conditions, with a maximum shut-off head of approximately 42–52 M. The 5 HP CDW High Head delivers lower flow (~350–500 LPM) but reaches shut-off heads of ~52–65 M — the right choice when TDH is the constraint rather than volume. Request the model-specific pump curve from the Cosmos team for exact duty-point selection.
What is the difference between a 5 HP and a 10 HP dewatering pump?
A 10 HP CDW Standard delivers approximately 3,000–3,800 LPM at rated conditions — roughly 1.5–2× the flow of a 5 HP model — with a maximum shut-off head of ~55–70 M. For sites with high groundwater inflow or where dewatering time is critical, the 10 HP significantly shortens pumping cycle time. Where inflow is manageable, a 5 HP is more energy-efficient. The 10 HP CDW High Head extends the head advantage further, reaching ~80–95 M shut-off — suited to tunnel dewatering and long discharge pipe runs.
Which dewatering pump HP is needed for mine dewatering?
Open-pit or adit mine dewatering at 20–60 M depth typically requires 15–40 HP CDW High Head pumps, where shut-off heads of 95–135 M cover the combined static lift and pipe friction losses. For underground shaft dewatering at depths exceeding 60 M, or where total dynamic head exceeds 90 M, the CDW Ultra High Head (50–120 HP, shut-off head up to 200 M) is the required specification. Cosmos supplies complete mine dewatering systems under EPEC contracts — 50+ mining projects per year — including hydraulic design, staged pump arrangements, and standby unit specifications.
Need Help Selecting the Right HP?
Share your site depth, required flow rate, and discharge pipe length with the Cosmos dewatering team for a same-day recommendation.
Mining, Tunnelling and Hydro Applications — Where the CDW High Head Excels
The CDW High Head submersible dewatering pump series is built for the most depth-demanding applications in Indian infrastructure: underground mine dewatering, metro bored tunnels, hydro power plant intake pits, and large civil projects requiring a high head dewatering pump rated between 40 M and 140 M. With shut-off heads up to 140 M and flow capacity to 2,200 LPM, the CDW High Head covers the full working range of high-pressure dewatering without the cost or complexity of an ultra-high-head unit.
Underground Mine Dewatering — Up to 140 M Head
Mine dewatering is one of the most demanding applications for any high pressure dewatering pump. Groundwater inflows in Indian coal mines, stone quarries, and metalliferous mines can reach 1,000–2,200 LPM at sump depths of 60–140 M. The CDW High Head is correctly specified for this duty.
Why the CDW High Head for mine dewatering:
- Shut-off head to 140 M — covers the majority of open-cast and shallow underground mine sumps in India (DGMS-permitted working depths and typical sump configurations)
- Flow to 2,200 LPM — handles sustained groundwater inflow at operating heads typical of Indian mine applications
- Solids handling to 12 mm — suitable for mine groundwater carrying fine grit and sand without slurry content (for slurry or coal-laden water, specify the Cosmos CSL Slurry Pump)
- 5–75 HP range — enables relay-pump staging across multiple mine levels without generator overload
- pH 5–8 tolerance — handles moderately acidic mine groundwater encountered in coal and limestone formations
For mine dewatering sumps deeper than 140 M, or where water is aggressively saline or slurry-laden, upgrade to the CDW Ultra High Head, which extends coverage to 200 M head with SS316 two-stage impellers and Viton seals.
→ Full mine dewatering application guide: Mining Dewatering — Cosmos Pumps
Metro Bored Tunnel Dewatering — Sustained Pressure Across Long Drives
Metro tunnel dewatering demands a different performance profile from site dewatering: the pump must maintain steady high-pressure discharge continuously over an extended tunnel drive (600 M–3 km), with groundwater ingress typically increasing as the TBM advances toward its deepest point.
CDW High Head capabilities for tunnel dewatering:
- Variable head capability from 40 M to 140 M — matches the progressive depth increase from shaft entry to maximum TBM drive depth in most Indian metro corridors
- Compact submersible form factor — fits within the restricted sump space of a bored tunnel working face; no surface footprint required
- Class H insulation (180°C rated) — supports 24-hour continuous operation essential in bored tunnel environments where pump downtime increases inundation risk
- Twin SS mechanical seals (TC vs TC) — certified for continuous high-head operation without seal failure from pressure cycling
Recommended configuration: Two-pump relay setup — one CDW HH in the tunnel face sump, one in the shaft sump — halves the head requirement per unit and provides N+1 redundancy. Cosmos technical team can assist with relay configuration sizing for your specific tunnel drive parameters.
→ Full tunnelling application guide: Tunnel Dewatering — Cosmos Pumps
Hydro Power Plant Intake Pits — Reliable Dewatering for Civil and Maintenance Works
Hydro power plant intake pits, penstock approach channels, and underwater gate chambers require periodic dewatering during inspection, maintenance, and construction phases. These applications combine elevated head (60–120 M at most Himalayan and Western Ghats hydro sites) with a requirement for clean-water handling and reliable continuous operation.
CDW High Head for hydro intake dewatering:
- 40–140 M head range — covers intake pit depths at run-of-river and storage reservoir hydro plants across Himalayan and peninsular hydro corridors
- Clean-water hydraulic efficiency — in pre-cleared intake pits without sediment loading, CDW HH delivers peak flow efficiency across the duty curve
- Nitride-hardened SS-410 impellers (HRC 52–55) — handles residual silt and sand typical of river-run hydro inlets without accelerated impeller wear
- Adjustable wear plate gap — allows field recalibration if site conditions shift during longer dewatering campaigns
Cosmos Pumps has served 30+ hydro-electric and thermal power plant dewatering projects annually and can provide EPEC support for complex intake dewatering campaigns.
CDW High Head vs CDW Ultra High Head — Selection Table
Use this table to confirm whether the CDW High Head or the CDW Ultra High Head is the correct specification for your site.
| CDW High Head | CDW Ultra High Head | |
|---|---|---|
| Shut-Off Head | 40 M – 140 M | 90 M – 200 M |
| Flow Rate | 350 – 2,200 LPM | 50 – 200 m³/h |
| HP Range | 5 – 75 HP | 50 – 120 HP |
| Solids Handling | Up to 12 mm | Up to 12 mm |
| Impeller Material | Nitride-hardened SS-410 | SS316 (2-stage) |
| Seal Type | Twin SS TC vs TC | Dual SiC vs SiC mechanical + oil seal |
| Motor Insulation | Class H (180°C) | Class H + thermal sensor |
| Saline/Abrasive Tolerance | Standard (sacrificial zinc anode option) | High (Viton rubber parts throughout) |
| Installation | Vertical | Vertical + horizontal |
| Standard Cable | 15 m PVC | 20 m |
| When to specify | Site TDH is 40–140 M; clean-to-mildly turbid water; standard mine, tunnel, construction, hydro duty | Site TDH exceeds 140 M; aggressive water (saline, abrasive); horizontal installation required; HP >75 needed from single unit |
Upgrade from CDW High Head to CDW Ultra High Head when:
- Sump depth or total discharge head exceeds 140 M
- Water contains high salinity, aggressive minerals, or abrasive fines at SG above 1.1
- Horizontal pump installation is required (inclined headings, horizontal sumps)
- Required flow at high head demands more than 75 HP from a single unit
CDW Ultra High Head — Full Specifications and Features
Project References — CDW High Head in Mining, Tunnel and Hydro Applications
| Project Type | Application | Approx. Head | Configuration |
|---|---|---|---|
| Metro Corridor Project, North India | Bored tunnel sump dewatering, twin-bore metro drive | ~120 M | CDW HH 50 HP, two-pump relay |
| Open-Cast Mining Project, East India | Open-cast mine sump dewatering | ~140 M | CDW HH 75 HP, dual-pump stage |
| Hydro Power Plant Project, North India | Intake pit dewatering during gate inspection, Himalayan run-of-river site | ~90 M | CDW HH 30 HP, single unit |
Cosmos Pumps completes 50+ mining dewatering projects and 30+ hydro-electric plant dewatering projects annually. Named project references available on request — contact our team via WhatsApp or email.
Frequently Asked Questions — High Head Dewatering Pump
What is a high head dewatering pump?
A high head dewatering pump is a submersible pump designed to discharge water against total dynamic heads (TDH) exceeding standard dewatering range — typically 40 M and above. The Cosmos CDW High Head series covers 40 M to 140 M; the CDW Ultra High Head extends this to 200 M. High head pumps are specified for underground mine dewatering, metro bored tunnels, hydro power plant intake pits, and infrastructure projects with deep sumps or long discharge runs.
What is the difference between CDW High Head and CDW Ultra High Head?
The CDW High Head (40–140 M, 5–75 HP) is the correct specification for the majority of Indian mine, tunnel, and high-pressure infrastructure dewatering applications. The CDW Ultra High Head (90–200 M, 50–120 HP) is required when site head exceeds 140 M, water is aggressively saline or abrasive (Viton seals, SS316 two-stage impeller), or horizontal installation is needed. The UHH also supports higher single-unit HP (to 120 HP) for very large sump inflows.
Can a high head dewatering pump be used for underground mine dewatering?
Yes. The CDW High Head with shut-off heads to 140 M and flows to 2,200 LPM handles the majority of Indian open-cast and shallow underground mine dewatering applications. For sump depths exceeding 140 M, specify the CDW Ultra High Head (to 200 M). For mine water containing heavy slurry or coal fines, the Cosmos CSL Slurry Pump is the correct product.
What total dynamic head is required for metro tunnel dewatering?
TDH for metro tunnel dewatering depends on tunnel depth, TBM drive length, and pipe friction losses. Most Indian metro corridors (DMRC, MMRC, Bengaluru Metro) operate at 15–30 M depth, with relay sump configurations yielding 40–120 M effective head per pump. The CDW High Head (40–140 M) covers this range in relay and single-pump configurations. Cosmos technical team can assist with sizing for your specific drive parameters.
What is the difference between a high head and a high pressure dewatering pump?
The terms are used interchangeably in Indian construction and mining specifications. “High pressure dewatering pump” typically refers to the pump’s ability to generate elevated discharge pressure to push water up a long vertical riser — which is exactly the function of a high head pump. The Cosmos CDW High Head is rated to 140 M shut-off head, equivalent to approximately 14 bar discharge pressure at zero flow.
How do I select between CDW High Head and CDW Ultra High Head for my site?
Start with your site’s total dynamic head (static lift + friction losses in discharge pipe). If TDH is below 140 M and water is clean to mildly turbid, specify CDW High Head. If TDH exceeds 140 M, water is saline or abrasive (SG >1.1), or horizontal installation is required, specify CDW Ultra High Head. Contact Cosmos technical team with your sump depth, flow requirement, and discharge pipe diameter for a specific recommendation.
Download Catalogue: Dewatering Pump CDW High Head
