Techniques for Clearing Tree Roots with a Sewer Jetter Nozzle

You're on a job, looking at your camera’s view of the main line, and the picture on the monitor tells you everything you need to know. Tree roots, packed wall to wall, choking the pipe. Thousands of techs routinely use hydro-jetting every day to go after tree roots, yet many still doubt that high-pressure water-jets can really clear roots. So, let's answer that question first: Can hydro jetting really remove roots? YES! If you're running a jetter with enough GPM, adequate PSI, and a jetting nozzle that’s built to cut and rip out roots – you can absolutely clear roots via hydro-jetting. But even with the right equipment and nozzles it takes some operator-technique to productively and effectively clear tree roots from sewers and drains.

That last part is where a lot of otherwise good jetting jobs fall short. Streams of high-pressure water from the right jetter can indeed penetrate root masses, but it’s not enough to just blast water at the root mass. You also need (a) the right nozzles to create water-jet cutting and ripping action, and (b) proper operator technique to work those tools effectively. 

In this blog we'll walk through the nozzle choices and the attack-techniques that can clear root masses rather than just penetrate them. 

Need help choosing the right nozzle before your next root job? Give us a call, we talk pipe and roots for a living.

Clearing Roots Takes Water-Jet Impact, Not Just Pressure

Water is your tool, thus it is GPM (water-jet flow) and PSI (water-jet velocity) working together that turn streams of water into a sufficient cutting force. GPM is the "muscle mass" of water-jet volume that impacts a root blockage like a projectile, while PSI creates the high-velocity sharpness of each water-jet, enabling water-jets to cut, shred, or rip out a root mass.  Just like an axe has more cutting-impact than a small hatchet, higher GPM flow has more impact than lower GPM.  How fast you can swing the axe or hatchet also makes a difference in cutting-power and that's where PSI matters, because higher PSI means faster water-jet speed. Therefore, if your jetter lacks GPM and/or PSI, even the best nozzles and operator technique may not be enough to clear the roots.

Nozzle Types for Root Cutting

"Basic" nozzles might get lucky and punch through a root mass but that doesn't get the roots cleared to restore full flow-capability to the line. Actual "cutting" nozzles can shred and tear up the roots then flush them away. There are several types of root-clearing nozzles to consider, each with a different mode of root-attack. Many operators actually own more than one type, deploying the cutter-nozzle that's best suited for the job at hand. Here's how the different types stack up, and where each one earns its place on a root job:

Forward-Cutting / Coring Nozzles (Reaper & Rotodrill Types)

A "forward-cutting" nozzle such as a Reaper or Rotodrill leads with a rotating nose-jet that has very aggressive “coring” action, aimed straight at the root-mass. Its job is to chew through the roots, opening a core through the blockage so the line can flow again. Think of it as the point man on the job; it might not clean the pipe wall-to-wall, but it’s the most aggressive nozzle-type to break through the stoppage to restore flow.

Slow-Rotating Scouring Nozzles (Warthog & Bulldog Types)

Once the root-mass is cored open, a slow-rotating cutting/scouring nozzle like the Warthog comes in behind it. These nozzles use high-impact, slow-rotating side jets to scour the pipe wall clean, taking out any remaining roots and other buildup that the coring nozzle leaves behind. Skip this step and you're left with a line that flows today and roots right back up in a few months or even weeks. 

Note: these slow-rotating nozzle types often do include a forward-coring jet, but it is much slower to cut into blockages than the higher-speed coring jet of a Reaper or Rotodrill. With these slow-rotating nozzles, the rotating rear-jets are the stars of the show.

Turbine-Style Nozzles (Root Ranger Types)

Turbine-driven nozzles like the Root Ranger give you cutting action without needing max GPM behind them. That makes them a solid choice for smaller portable jetters in the 4-5 GPM range. You give up some raw cutting force compared to a faster, high GPM setup, but you gain flexibility on jobs where a bigger jetter isn't available.

So why not use a Root Ranger on all root jobs, even with larger high-GPM jetters? You can – in fact there are Root Ranger models that can handle over 20-GPM – but the downside is that the cutting jets of a Root Ranger (or an Enz Reverse-Rotodrill) are on the side of its nozzle-body, which requires the operator to twist the hose to work the nozzle’s size-mounted waterjet around to cover all sides of the pipe. While not as handy as using a centered nozzle like the Warthog or Reaper that does not require twisting, Root Rangers are very effective at attacking roots when they are properly "aimed" (via your sewer camera) before firing, often making them the best choice to cut out a stubborn taproot-remnant.

Chain-Flail Nozzles (Water-Jet Driven Chain Cutter Types)

Rotating chains powered by water-jet thrust used to be the only root-cutters available for jetters running less than 15-GPM, but the radical advancement of the aforementioned cutting nozzles in the last 25 years has moved these high-maintenance chain-flail nozzles to more of a de-scaling role in pipes. However, chain-flails are still commonly used to scrape out leftover root-danglers that a water-jet nozzle leaves behind, especially when prepping to re-line the pipe.

None of these four nozzle types are entirely interchangeable, and that's the point. What quickly tears through a heavy mass to restore flow might not touch buildup or remnants on the walls of the pipe. The nozzle that matters most is the one that matches the problem you’re facing in the pipe, and the jetter you're running behind it.  Are the roots creating a total stoppage, or are they just reducing the flow-path? Does your jetter produce “rooter-class” GPM and PSI, or is it a smaller portable unit? There's no one-size-fits-all nozzle here, hence the various types and sizes.

PRO TIP: Just because a nozzle rotates its jets doesn’t mean it is a “root cutting” nozzle! Rotating Grease-Hog and fast-spinning “polishing” types excel at their purposes but they are poor root-cutters.

Tactics & Techniques for Attacking Root Masses & Other Stoppages

When roots have built up into a full stoppage, here's how to work the mass without losing your nozzle in it.

1. Run a nozzle with a rotating, forward-facing “coring jet” to open the mass.

PRO TIP: If the line is backed up, look for a jetting-access that allows the nozzle to approach from the dry side of the stoppage. Without standing water in the way, the nozzle’s water-jets will chew into the blockage much faster, and you’ll get cleaner camera views of the blockage, as well as your nozzle’s progress. 

2. Don't let the nozzle’s front coring-jet immediately bury itself in the mass. Back it off about 2 inches so it has room to chew a decent-sized path through the blockage.

3. Pause and check your progress on the camera as you go. Keep the camera pulled back a safe distance while you're actively jetting.

PRO TIP: Avoid the temptation to “ram-rod” the nozzle into the blockage – if the nozzle has a forward "coring" jet then you need to “let it eat” for best results! Slowly advance the nozzle as it eats away at the mass instead of trying to force it through.

The “One-Two Punch” Root Clearing Method

A lot of experienced operators run coring and scouring nozzles back-to-back in the same line as a “One-Two Punch” to fully clear the pipe: 

(1) Run a coring nozzle through the blockage to restore flow

(2) Follow it with a slow-rotating scouring nozzle to clean the pipe wall-to-wall. It's a simple sequence that gets you a fully cleared and scoured line that’s ready to show your customer, or as a prep for re-lining.

We've broken down the full technique, timing, and sequencing in our guide to the One-Two Punch Method. Want to see these nozzles in action first? Watch these and many more nozzle demos on our channel.

Tactics for Attacking “Bird’s Nest” Roots and Other Buildup 

Not every root problem stops the line cold. “Bird's nest” intrusions can build in the pipe without fully blocking flow, and they call for a different approach:

• Use a nozzle with rotating rear jets that have ample cutting action, enough to grab the growth and cut off its taproot. 

• Before jetting, use your camera to confirm the nozzle is aligned to the infested area, then work the nozzle in short back-and-forth movements (repeatedly around 8-inches forward and back) to chew away at the root-infested area. Keep the camera-head back a safe distance while you're actively jetting, then check results again with your camera after jetting. 

Common Mistakes That Leave Roots Behind

Even good operators leave root fragments behind sometimes. Or maybe the nozzle doesn’t seem to cut as it once did. Usually it traces back to one of three things.

• Worn out orifice tips. Nozzle orifices blasting high-velocity water gradually wear down due to the erosion, which turns a nozzle's sharp cutting jets into a dull spray that's lost its cutting-edge, and roots barely notice it. It’s literally like trying to cut wood with a dull knife. If you use your root-cutting nozzle regularly, plan to replace its orifice-tips every year as routine maintenance.

• Plugged orifices. A plugged orifice-jet quietly kills your nozzle’s cutting-power without giving you an obvious warning on the reel. The gauge still reads full pressure but there’s a huge void in water-output. Check your orifices after every job to make sure they’re clear..

• The Nozzle’s rotating-action is stalled. Since we typically cannot see the nozzle working in the line, it is easy to miss that its rotating-action may have failed. If the nozzle doesn’t seem to be cutting, pull it back to check if it is freely rotating. Shut down and pull out the nozzle if necessary.

All three tie back to the same habit: checking your nozzles before they check you. For the full walk-through on catching worn tips and plugged orifices before they cost you a callback, see our guide to Nozzle Maintenance.

Clear the Roots, Don’t Just Punch Through Them 

Tree roots love sewer-water and the freedom to grow in pipes. What separates a complete root-cutting job that holds for many months or years from one that calls you back in weeks is whether you actually clear the roots or just blow a hole through them. If you match the right nozzle to the roots at hand, run a jetter with the GPM and PSI to power it, and back it up with smart tactics and techniques, you'll walk away with a line that's actually cleared and scoured for the long term. That’s a line you can confidently say is ready for your camera to show the customer.

Get equipped, and get jetting! Visit our online store to browse root cutting nozzles built for the job, or give us a call if you want help picking the right one for your trucks.

FAQ: Jetting Tree Roots

Can hydro jetting really remove roots?

Yes. Hydro jetters with enough GPM and PSI power to run a nozzle built with proper water-jet cutting action can efficiently remove root masses. High-pressure water pressure alone, without the right nozzle behind it, tends to just blast past the roots without cutting them out.

Can hydro jetting damage pipes?

Jetting is safe on typically sound pipes when the PSI and nozzle are matched to the pipe's condition. Older or already deteriorated pipe is a different story, which is why a camera inspection before you jet is worth the extra few minutes to evaluate the pipe’s condition before you commit to max water-jet pressure and flow on the first pass.

JETTERS NORTHWEST is a 20+ year-old product line of Seattle Pump & Equipment Co., a service and sales center for jetters for over 50 years.