Drains, CCTV surveys and root removal for Harrow’s inter-war homes, grease traps for its high streets, and septic tanks on the green-belt edge.
Much of Harrow was built in the 1920s and 30s, as the Metropolitan line brought new suburbs to Pinner, Rayners Lane, North Harrow and Kenton. Those streets of semis and bungalows still have many of their original clay drains, now nearly a century old, and roots and cracks are the most common reasons we’re called out.
Harrow sits on London Clay, which shrinks in dry summers and cracks old pipes. Many homes have been extended at the back, into the loft or with outbuildings, adding new connections to old drains. The high streets of Harrow, Wealdstone and Rayners Lane have restaurants and takeaways that need grease traps emptied.
On the green-belt edge around Harrow Weald and Old Redding, a few homes still rely on septic tanks. Our crews work in London most days and we answer the phone 24 hours a day.
Pinner, North Harrow and Rayners Lane are full of 1930s semis whose clay drains were laid when the Metropolitan line arrived. When roots or a slipped joint finally block one, we jet it clear, cut the roots back and show you the camera footage so you can see the problem for yourself.
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Garden offices, loft conversions and side returns all add new pipework. A survey beforehand tells your builder where the old runs are, and one afterwards confirms nothing was crushed during the work.
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Restaurants and takeaways on Harrow’s high streets need grease traps emptied regularly. We set up a schedule and leave a waste transfer note every time.
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A few homes around Harrow Weald and the green belt are off the mains. We empty septic tanks and cesspits and service treatment plants.
Learn moreLocal knowledge
Metroland suburbs on London Clay.
Many homes still have their original clay drains, now nearly a hundred years old.
Clay shrinks and swells with the seasons, cracking and shifting old pipes.
New rooms are often connected to old drains. Survey before you build.
Local to you
We cover Harrow and the neighbouring parts of north-west London.
Harrow · and neighbourhoods
Surrounding areas · including a few homes on septic tanks
If you’re in or around Harrow, we cover you. Call with your postcode and we’ll confirm.
Why Harrow customers use us
Whether it’s a root-blocked drain in Pinner or a takeaway grease trap in Wealdstone, here’s what you can expect.
We’ve been emptying tanks and servicing systems since long before most of the kit on the market existed.
We show you what the camera found, so you understand the problem before deciding on a repair.
Emergency call-outs 24 hours a day, 365 days a year, with a real person answering the phone.
Regular customers get a reminder when their next empty or service is due.
Tankers from 2,000 to 4,000 gallons, jet/vac combination units, CCTV survey kit and confined space teams for pump station wet wells.
SafeContractor, Achilles UVDB and RISQS approved, so we can get onto managed sites and meet your contractor checks.
Checkatrade
From 134 reviews · Read them
From 63 reviews · Read them
Scores as of September 2026
★★★★★So glad we found them. The team was professional, courteous and helpful. They came the next day and pricing is way more competitive than a national chain. Will be using them again in a year's time to service the pump. Thanks again!
Drake I. Google review
★★★★★We've been using Clearmasters for several years now and they've been great. We're in a tricky area to get to but they always make a plan without complaint. Great team! Highly Recommended.
★★★★★Had a very good experience with Clear Masters. They provide an excellent, professional service, friendly and helpful, on time as per the agreed price
How it works
The same simple process for every job.
Step 1
Call us or book online and tell us what’s happening. If you’re planning building work, tell us what and when.
Step 2
We send the right van or tanker. It helps if:
Step 3
You get a waste transfer note for anything we take away, and a written report after a survey or service. If it’s a regular job, we’ll remind you when the next one is due.
Free, no-obligation quote
Tell us what you need and we’ll come back with a price. If something’s overflowing, call us now.
Questions answered
What homeowners and businesses in Harrow ask us most.
At nearly a hundred years old, clay drains have usually moved, cracked or let roots in somewhere. Many still work fine; when they don’t, a camera shows exactly where the weak spot is.
It can, if it’s built over a drain run or adds a new connection. Find out where the drains are first, which a quick survey will show.
Usually, especially under patios, drives or extensions. It isn’t right for every pipe, which is why we survey first.
If the pipe serves more than one property, it’s usually the water company’s responsibility. We’ll tell you where the blockage is so you know who to call.
Yes, including the few homes there that still have septic tanks or cesspits.
Our crews are in north-west London most days. Ring 03333 233566 for a time.
Got a different question? Call 03333 233566 or send us a message.
We're independently vetted and certified so you can trust who you're letting onto your site.
Health & safety pre-qualification accreditation, verifying our processes meet recognised safety standards.
Railway Industry Supplier Qualification Scheme — approved to work safely within the rail industry supply chain.
Utilities Vetting Database membership, confirming we meet the utilities sector's supply chain standards.
Vetted and approved under the local authority's trusted trader scheme for honesty and fair dealing.
Members of the National Association of Drainage Contractors, the UK trade body for the drainage industry.
Registered with the Environment Agency, so your waste is handled and disposed of fully within the law.
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