Well Drop Pipe: PVC vs. Poly vs. Steel Selection Guide

The drop pipe—the pipe running from your submersible pump to the surface—is a critical component that must handle high pressures, support the weight of the pump and water column, and last for decades submerged in groundwater. Choosing the right material affects installation ease, longevity, service access, and cost.

This guide compares the three main drop pipe materials: PVC, polyethylene (PE/poly), and galvanized steel, helping you understand which is best for your specific situation.

What Is Drop Pipe?

Drop pipe (also called "riser pipe" or "discharge pipe") connects your submersible pump to the well head at the surface. It must:

• Carry water: Deliver water from pump depth to surface at required flow and pressure
• Support weight: Hold the weight of the pump plus the water column (which can be hundreds of pounds)
• Resist pressure: Handle both operating pressure and water hammer
• Last submerged: Remain strong for decades in groundwater conditions

The submersible pump wire typically runs alongside or inside the drop pipe, secured with zip ties or tape.

Drop Pipe Material Comparison

PVC (Polyvinyl Chloride)

PVC is rigid plastic pipe, typically Schedule 80 or Schedule 120 for well applications.

Pros:

• High pressure rating (up to 450 PSI for Schedule 80)
• Excellent for deep wells (300+ feet)
• Rigid—won't collapse under suction
• Doesn't corrode
• Long lifespan (25-30+ years)
• Relatively low cost per foot

Cons:

• Rigid—can crack if well isn't straight
• Requires many threaded or glued joints (potential leak points)
• Can become brittle in UV light (above-ground sections)
• Heavier than poly for same capacity
• More installation labor (joining sections)

Best for: Deep wells, high-pressure systems, crooked wells where rigidity helps guide the pump

Polyethylene (PE/Poly)

Flexible plastic pipe, often called "poly pipe" or by brand names. Comes in rolls for shallow wells or coils for deeper applications.

Pros:

• Flexible—follows well curvature easily
• Fewer joints (often one continuous length)
• Easier installation—can lower by hand without a rig
• Won't crack or shatter
• Lighter weight than PVC
• Good corrosion resistance

Cons:

• Lower pressure rating than PVC (typically 160-200 PSI)
• Depth limited (typically under 200-250 feet)
• Can collapse under high suction or vacuum conditions
• Requires special insert fittings
• Can be damaged by petroleum products

Best for: Shallower wells (under 200 feet), DIY installations, wells with curves or offsets

Galvanized Steel

Traditional material—steel pipe coated with zinc for corrosion resistance.

Pros:

• Extremely strong and rigid
• High pressure rating
• Can handle any depth
• Tolerates rough handling
• Can be used to pull stuck pumps

Cons:

• Heavy—requires service rig for installation
• Corrodes over time (faster in acidic water)
• Zinc coating can affect water taste initially
• Expensive (material and installation)
• Joints can seize from corrosion
• Shorter lifespan than plastic (15-20 years typical)

Best for: Very deep wells, areas where plastic isn't allowed by code, situations requiring maximum strength

Comparison Chart

Sizing Drop Pipe

Size by Flow Rate

Undersized pipe creates friction loss, reducing the water that reaches your pressure tank:

Consider Depth

Deeper wells mean:

• More friction loss (longer pipe run)
• More weight to support
• Higher pressure at the bottom

For deep wells (300+ feet), upsizing the pipe helps compensate for friction loss and ensures adequate flow.

Check Pump Specifications

Your pump's documentation specifies the discharge connection size and maximum/minimum pipe diameters. Using a smaller pipe than rated reduces pump efficiency and can void warranty.

Installation Considerations

PVC Installation

• Use Schedule 80 or higher for wells
• Threaded joints (not glued) allow future service
• Apply Teflon tape or pipe dope to threads
• Don't over-tighten (can crack threads)
• Use stainless steel pipe clamps with pump wire
• Install torque arrestors to prevent pump rotation

Polyethylene Installation

• Use insert fittings designed for PE pipe
• Secure with stainless steel clamps
• Avoid kinks during installation
• May need weight or time to straighten from coil
• Tape or tie pump wire at regular intervals

Safety Equipment

Regardless of material, professional installations include:

• Safety rope: Stainless steel cable as backup if pipe fails
• Torque arrestors: Prevent pump from spinning and unscrewing
• Check valve: Prevents backflow and maintains prime

Common Drop Pipe Problems

Leaking Joints

Causes: Loose connections, cracked threads, failed sealant, corrosion

Signs: Reduced flow/pressure, pump runs longer, air in lines

Solution: Pull pipe, repair or replace affected joints

Collapsed Pipe

Causes: Water hammer, vacuum on startup, pipe material exceeded for depth

Signs: Severely reduced flow, pump strains

More common with: Polyethylene in deep applications

Corrosion (Steel)

Causes: Acidic water, age, dissimilar metals creating galvanic corrosion

Signs: Rust particles in water, reduced flow, eventual leaks or breaks

Prevention: Address water chemistry or switch to plastic

Cracking (PVC)

Causes: Over-tightened connections, impact, UV exposure, chemical damage

Signs: Visible cracks, leaks, reduced pressure

Prevention: Proper installation, protect above-ground sections

When to Replace Drop Pipe

• During pump replacement (opportunity for upgrade)
• Evidence of leaks or cracks
• Corroded steel pipe (15-20 years old)
• After pulling a stuck pump (inspect for damage)
• Switching to a higher-capacity pump
• If current pipe is undersized

Tip: If replacing the pump, replacing 20+ year old drop pipe at the same time often makes sense—the labor to pull the pipe is already being done.

Costs

Installation labor: Typically included in pump installation cost. Separate drop pipe replacement runs $300-800+ depending on depth and access.

Frequently Asked Questions