Cresline Plastic HD-CTS (SDR-9) Plastic Polyethylene Pipe

A straightforward, pressure-rated CTS option for underground runs

I put this 1-inch CTS polyethylene pipe to work replacing a tired galvanized water service line between a rural meter pit and a farmhouse. The run was just shy of 200 feet, straight enough to take advantage of a continuous coil with only a few gentle sweeps. I wanted something pressure-rated, reliable underground, and simple to handle without specialized fusion tools. This Cresline CTS pipe fit that bill—provided you understand what CTS means and plan your fittings accordingly.

CTS vs. IPS: make sure you buy the right size for your fittings

The most important thing to know is that this is CTS (copper tube size), not IPS (iron pipe size). That means 1-inch here refers to the copper-nominal size. The outside diameter is about 1.125 inches, and with an SDR-9 wall profile, the wall thickness is roughly one-ninth of that. In practical terms:

• You need CTS-compatible fittings—pack joint/compression fittings labeled for 1-inch CTS, or insert/barbed fittings specifically sized for 1-inch CTS.
• Standard 1-inch IPS HDPE or 1-inch PEX barb fittings will not fit correctly.
• The internal diameter is smaller than 1-inch IPS pipe, which affects flow capacity.

If you’re transitioning to copper or to a meter yoke, look for brass CTS pack-joint couplings from the usual municipal brands (Ford, Mueller, A.Y. McDonald, etc.). On my install, I used CTS-to-MIP pack-joint adapters at both ends, then adapted to the existing plumbing.

Handling and installation

The 300-foot coil arrived neatly strapped and clearly print-lined with size and SDR. It’s a dense coil—expect some weight and spring. A few handling notes from the trench:

• Uncoiling: Lay the coil on its side and “roll” it along the trench path on a warm day. Trying to pull loops off the top is a recipe for twists and kinks.
• Bend radius: SDR-9 has a stout wall and a bit more stiffness than thinner SDR pipes. Plan for sweeping arcs, not tight turns. I kept bends gentle, similar to the rule-of-thumb 20x OD.
• Kinks: If you do kink it, cut out the damaged section; don’t try to rely on heat to reform the wall for a pressure line.
• Bedding and backfill: As with any plastic service line, get the sharp rocks out of the trench bottom. A few inches of sand or screened soil makes a big difference for long-term peace of mind.
• Tracer wire: The pipe is non-metallic. I taped a 14 AWG solid copper tracer wire along the full run and brought it up at both ends for future locating.
• Connections: For insert fittings, I used stainless steel worm-drive clamps rated for underground service—double-clamped, with the screw housings offset 180 degrees. Warming the pipe end in a bucket of hot water makes insertion much easier.

None of this required fusion equipment, and once it was laid out, the continuous coil eliminated buried joints—one of the big advantages of buying a 300-foot run even if you don’t use every foot.

Performance in service

I pressure-tested the line to 100 psi for 24 hours before backfilling; there was no measurable drop at the gauge. That’s the kind of outcome I expect from fresh polyethylene with solid connections, but it was reassuring nonetheless.

Flow-wise, remember the CTS sizing. The ID is smaller than 1-inch IPS. For my application—a single-family service line with a modest static head—it’s more than sufficient. If you’re feeding a large irrigation manifold or looking to minimize friction losses over long distances, you might want to run the numbers on head loss. CTS at SDR-9 is a robust wall, but you don’t get the same cross-sectional area as an IPS of the same nominal size.

Temperature and pressure behavior have been uneventful. Polyethylene tolerates brief cold snaps better than rigid plastic because it can flex, but it’s not freeze-proof. Bury it below frost depth. On the warm side, it’s for cold-water service; don’t use it for hot water or compressed air.

Build quality and markings

The pipe I received had consistent wall thickness and clean, readable print lines with size, SDR, and use classification. The black compound resists UV better than natural plastic thanks to carbon black, but like most service-line PE it isn’t meant for long-term sun exposure. If it needs to sit out for a few days during a job, I’m not concerned; for permanent above-ground runs, choose a product rated for that.

“Made in USA” is a small but welcome note. It’s not a guarantee of performance by itself, yet in my experience it often correlates with better process control and traceability.

Where it fits—and where it doesn’t

This pipe excels in a few scenarios:

• Residential or light commercial cold-water service lines from meter to building where CTS fittings are the norm.
• Irrigation mains that will be buried and kept under reasonable pressures.
• Retrofits where you want minimal joints—long coil, simple handling, and common compression fittings.

It’s not the right choice if:

• Your system is built around IPS fittings and diameters.
• You need maximum flow in a 1-inch nominal envelope; the smaller ID of CTS may be limiting.
• You want a pipe for above-ground exposure, hot water, or compressed air.

If you’re working with a municipality or under a strict code environment, check the job specification for ASTM standards (for example, D2737 for PE CTS service tubing) and potable-water listings. Verify the print line to match the spec before you cut it.

Tips from the install

A few practical details that helped:

• Measure before you trench. I left the coil intact until I could lay it straight and mark exact cut points—less waste, cleaner ends.
• Square cuts and deburring matter. A ratcheting plastic pipe cutter makes quick, square cuts; a light deburr helps compression ferrules seat cleanly.
• Use the correct stiffeners/inserts with compression fittings. Most CTS pack joints include them; double-check sizing.
• Give yourself a service loop at both ends. A gentle extra sweep near the meter and entry point makes future maintenance simpler.
• Label and photo-document. Before backfill, I photographed the run with a tape measure for landmarks. It’s saved me more than once.

Pros

• Pressure-rated SDR-9 wall with a durable feel
• Long, continuous coil reduces underground joints
• Plays nicely with common brass CTS compression/pack-joint fittings
• Easy to cut and handle with basic plumbing tools
• Made in the United States with clear print lines

Cons

• CTS sizing can trip up anyone expecting 1-inch IPS; fittings are not interchangeable
• Smaller internal diameter than 1-inch IPS reduces maximum flow
• Coil memory requires thoughtful uncoiling to avoid kinks
• Not intended for hot water, compressed air, or permanent above-ground exposure

Bottom line

I’m happy with this pipe in the role it’s designed for: a robust, CTS-sized, pressure-rated polyethylene service line that installs with standard compression or insert fittings and stays out of sight, out of mind underground. It handled cleanly, passed a pressure test without drama, and the 300-foot coil let me run a continuous line with no buried joints.

I recommend it—specifically to anyone who needs 1-inch CTS SDR-9 for water service or buried irrigation and has the right CTS fittings on hand. If your fittings or design are based on IPS sizing, or you need the larger ID for high-flow applications, choose an IPS pipe instead to avoid frustration.