Septic tanks, cesspits and treatment plants emptied, serviced and repaired in Sevenoaks and the villages of the Kent Downs and the Weald.
Sevenoaks is a prosperous town on the greensand ridge in west Kent, only a short drive from our office in Smallfield. The town is on mains drainage, but the countryside around it, from Westerham, Brasted and Ide Hill to Ightham, Underriver and Sevenoaks Weald, is full of large homes, farms and estates on septic tanks, cesspits and treatment plants.
The ground here changes quickly. The chalk of the North Downs rises to the north, the sandy greensand ridge runs through the town, and the heavy Weald clay begins just to the south. Big gardens, long drives and mature trees add their own challenges, from long private drains to roots in the pipes.
Our crews work in west Kent most days and we answer the phone 24 hours a day, 365 days a year.
We empty septic tanks and cesspits for homes, farms and estates around Sevenoaks. Long drives and tanks tucked away at the far end of big gardens are normal for us; tell us about access and we’ll bring enough hose.
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Many larger homes around Sevenoaks have treatment plants. Our engineers service them at least once a year, check the blower, diffusers and pumps, and send a written report.
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Mature trees and long private drains mean roots are a common cause of blockages. We clear them with high-pressure jetting and root cutting, and survey the drain with CCTV.
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A septic tank survey tells you what system a property has and whether it meets the General Binding Rules. If it doesn’t, we can install a treatment plant or drainage field.
Learn moreLocal knowledge
Downs, greensand and Weald, all within a few miles.
Much of the countryside around Sevenoaks is protected. New drainage may need careful planning.
Sandy greensand drains well; Weald clay to the south doesn’t. Drainage fields on clay struggle in winter.
On big plots, the drain from house to sewer can be long and entirely yours. Knowing where the chambers are saves time.
Local to you
We cover Sevenoaks and the villages around it.
Sevenoaks · town and nearby
Surrounding villages · where septic tanks are common
If you’re in or around Sevenoaks, we cover you. Call with your postcode and we’ll give you a date.
Why Sevenoaks customers use us
Whether it’s a cesspit at a farmhouse near Underriver or a treatment plant in Ide Hill, here’s what you get.
We’ve been emptying tanks and servicing systems since long before most of the kit on the market existed.
Tankers from 2,000 to 4,000 gallons, jet/vac combination units, CCTV survey kit and confined space teams for pump station wet wells.
Our engineers and most of our tanker drivers hold current confined space entry certificates, and the engineers carry the most common parts.
A waste transfer note with every collection, and a written report after surveys and services.
Regular customers get a reminder when their next empty or service is due.
Emergency call-outs 24 hours a day, 365 days a year, with a real person answering the phone.
Checkatrade
From 134 reviews · Read them
From 63 reviews · Read them
Scores as of September 2026
★★★★★I've used Clearmasters for the past year and they've always been outstanding! They are very efficient to deal with in the office, they are very reasonably priced and their engineers are among some of the most professional i've met. I would highly recommend them to anyone.
Checkatrade review Checkatrade · TN16
★★★★★Very friendly and helpful staff. Throughout the initial diagnosis and then the subsequent fitting of new equipment, each step was explained to me such that I understood why it was being undertaken and as a result I was confident that I wasn't being ripped off. Will use Clearmasters for all future services with regard to my treatment plant.
★★★★★Have always found Clear Masters to be very friendly, professional and helpful. They provided the service to me on time at the pre-agreed amount
How it works
Simple and the same every time.
Step 1
Call us or book online and tell us what system you have and how to reach it.
Step 2
We book a date and send the right tanker or engineer. 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 around Sevenoaks ask us most.
Usually, yes. Our tankers carry long hoses. Tell us roughly how far and we’ll plan for it.
South of the greensand ridge, Weald clay drains slowly and fields can be saturated through the winter.
Sometimes, especially in the Kent Downs National Landscape. The system must also meet the Environment Agency’s rules. Check with Sevenoaks District Council first.
Yes. Roots find their way into joints and cracks, then grow and catch everything that flows past. Jetting and root cutting clear them; a survey shows if a repair is needed.
Yes. We service and repair treatment plants throughout the villages around Sevenoaks.
Our office is in Smallfield, a short drive away, and our crews work in west Kent most days. Call 03333 233566 at any 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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