CLEARMASTERS
in drainage
levels first
Regulations
and reinstate
for aftercare
Groundworks
From one new manhole to a complete off-mains system
We’ve been working on drains for 34 years, and groundworks is where it all comes together: digging in new drainage, putting in the chambers, tanks and soakaways that go with it, and putting the ground back afterwards.
Before we design anything we can trace and survey the existing drains, and once the work is done we can look after it with treatment plant servicing and soakaway maintenance.
We do this work across Surrey, West Sussex, East Sussex, Kent, Hampshire and London, with tankers and engineers in each area most days.
Every job starts with a survey. We check the levels, the ground, what’s buried there already and where the water can legally go, then design the work to the Building Regulations and the relevant British Standards.
Because we also empty, jet, survey and service drainage systems every day, we build things the way we’d want to maintain them: with the right access, in the right place, and easy to look after.
Our groundworks services
What we install and repair
Treatment plant installations
New and replacement sewage treatment plants, including septic tank upgrades to meet the 2020 rules.
Soakaway installations
Percolation tested, designed and installed crate soakaways for roofs, drives and yards.
Manhole installations
New manholes and inspection chambers with the right cover for where they sit.
Inspection and sampling pits
Access and sampling points for treatment plants, trade effluent and permits.
Drainage fields
Percolation tests, design and new or replacement drainage fields.
Gully repairs and clearance
Broken grates, sunken frames and failed gullies repaired or replaced.
Drain excavation and replacement
Collapsed or badly damaged drains dug out and replaced.
No-dig drain lining
Cracked drains repaired from the inside when digging isn’t needed.
How it fits together
The drainage around a typical property
A house off the mains sewer, seen from above. Hover over or tap the numbers to see each part, and follow the links to the service that installs it.
- 1ManholesAccess points wherever the drain changes direction, depth or joins another.
- 2Treatment plantTreats the sewage where there’s no mains sewer.
- 3Sampling chamberWhere the treated water can be checked.
- 4Drainage fieldSpreads the treated water into the ground.
- 5SoakawayTakes rainwater from the roof and drive.
- 6GullyCollects surface water from the drive, yard or road.
- 7Drain runsDug and replaced when they’ve collapsed, or lined without digging.
Before you dig
Do you need permission for drainage groundworks?
Repairing or replacing a drain like for like doesn’t usually need planning permission. Most new drainage does need to meet the Building Regulations, and some work needs approval before it starts.
New treatment plants and new drainage generally need Building Regulations approval. Discharging treated sewage to the ground or a watercourse has to meet the Environment Agency’s General Binding Rules, or you’ll need a permit. Connecting to a public sewer, building near one, or working in the road needs the water company’s or highway authority’s consent.
We’ll tell you what your job needs at the survey, and help with the applications.
Work that usually needs approval
- A new sewage treatment plant or septic tank replacement
- A new drainage field or discharge to a watercourse
- A new connection to a public sewer
- Building over or within about 3 m of a public sewer
- Any digging in a public road or pavement
On the day
How a groundworks job runs
Survey
We visit, check the levels, ground and access, trace any existing drains and agree what you need.
Quote and design
A clear written quote, with the design and any approvals the job needs.
Groundworks
We dig, install and connect, keeping the site safe and tidy as we go.
Test and reinstate
Everything is tested, the ground is put back, and you get the paperwork and advice on looking after it.
Why Clearmasters
Why choose Clearmasters?
With 34 years in drainage, we know what makes a system easy to live with, because we’re the people who get called when one isn’t. We build it right, and we can look after it afterwards.
Ask us a questionWe survey before we dig
Levels, ground conditions, buried services and where the water can go, checked before we quote.
Done to the rules
Designed and built to the Building Regulations, British Standards and the manufacturer’s instructions.
We look after it afterwards
We empty, jet, survey and service what we install, so you have one firm for the life of the system.
Our own kit
Our own tankers, jetters and CCTV cameras, so surveys and aftercare don’t wait on anyone else.
What our customers say
Checkatrade
From 134 reviews · Read them
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Scores as of September 2026
Questions answered
Drainage groundworks FAQs
Do I need planning permission for drainage groundworks?
Straightforward repairs and replacements usually don’t. New treatment plants, soakaways for larger sites, and anything connecting to a public sewer may need approval from your council, the Environment Agency or the water company. We’ll tell you what applies at the survey.
Do you do small domestic jobs?
Yes. We do everything from a single new inspection chamber or a soakaway for an extension to complete off-mains systems and commercial surface water drainage.
Do you give free quotes?
Yes. Call 03333 233566 or send us a message, and we’ll arrange a survey and a no-obligation quote.
Can you survey my existing drains first?
Yes. We often start with a CCTV drain survey or drain tracing, so we know exactly what’s there before we design anything.
Which areas do you cover?
Surrey, Sussex, Kent, Hampshire and London.
Got a different question? Call 03333 233566 or send us a message.
Related services
Fully accredited & compliant
We're independently vetted and certified so you can trust who you're letting onto your site.
SafeContractor
Health & safety pre-qualification accreditation, verifying our processes meet recognised safety standards.
RISQS
Railway Industry Supplier Qualification Scheme — approved to work safely within the rail industry supply chain.
Achilles UVDB
Utilities Vetting Database membership, confirming we meet the utilities sector's supply chain standards.
Trading Standards Approved
Vetted and approved under the local authority's trusted trader scheme for honesty and fair dealing.
NADC Member
Members of the National Association of Drainage Contractors, the UK trade body for the drainage industry.
Registered Waste Carrier
Registered with the Environment Agency, so your waste is handled and disposed of fully within the law.