Emptying, servicing and repairs for septic tanks, treatment plants and drains in Winchester, along the Itchen valley and across the chalk villages around the city.
The city of Winchester is on mains drainage, but step outside it and that changes quickly. Villages like Sparsholt, Crawley, Owslebury and Micheldever, and the farms and cottages scattered across the downs between them, depend on septic tanks, cesspits and package treatment plants. Those systems are what we mostly look after around Winchester.
Winchester sits on chalk, and the River Itchen that runs through it is one of England’s best-known chalk streams. That matters for anyone with a private sewage system. Chalk lets water through quickly, the groundwater beneath it supplies drinking water, and the Itchen feeds into the Solent, which is under pressure from nutrients. So a tank or plant that isn’t working properly is more of a problem here than in many places.
Our tankers and engineers are working in Hampshire almost every day, so Winchester isn’t an occasional trip for us. Regular emptying and servicing is booked at a time that suits you, and if something goes wrong we answer the phone 24 hours a day, 365 days a year.
Many homes around Winchester have replaced an old septic tank with a package treatment plant, often because of the rules on discharges near watercourses. A plant only cleans the water properly if the blower, diffusers and pumps are all working, so it needs servicing at least once a year. Our engineers service the common makes, carry the most common parts, and give you a written report on what they found.
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We empty septic tanks and cesspits at cottages, farmhouses and estates in the villages around the city, using tankers that hold between 2,000 and 4,000 gallons. While we’re there we check the inlet and outlet and tell you if anything looks wrong. Cesspits have no outlet and fill much faster, so we can set up regular collections and book them in ahead.
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If you’re buying a house near Winchester with its own drainage, it’s worth knowing what you’re taking on before you exchange. A survey tells you what the system is, what condition it’s in, where it discharges, and whether it meets the General Binding Rules. It’s also the first step if you’re thinking about replacing an old tank with a treatment plant.
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Older properties in and around the city often have clay drains that have been added to over the years. We clear blockages with high-pressure jetting, and when a drain keeps blocking we put a camera down it so you can see the cause, whether that’s roots, a cracked pipe or a joint that’s moved, before deciding on a repair.
Learn moreLocal knowledge
Chalk, chalk streams and the Solent all affect how private drainage is treated here.
Chalk drains freely, so a soakaway may work well, but the water it reaches is used for drinking water. Near the most sensitive sources, a new discharge to ground needs an Environment Agency permit.
The Itchen is a chalk stream with special protection. A septic tank that discharges into a ditch or stream must be upgraded under the General Binding Rules.
Winchester City Council expects new homes to be nutrient neutral. If you’re building or converting, ask early about what that means for your treatment plant.
Local to you
From the edge of the city out to the villages of the Itchen valley and the downs, here’s where we work around Winchester.
Winchester · city and nearby
Surrounding villages · where private drainage is common
If you’re in or around Winchester, call with your postcode and we’ll confirm.
Why Winchester customers use us
Whether it’s a treatment plant on a farm near Sparsholt or a cesspit outside Owslebury, here’s what you get from us.
We’ve been emptying tanks and servicing systems since long before most of the kit on the market existed.
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.
Tanks, treatment plants, pump stations, grease traps and drains, all handled by one team.
Tankers from 2,000 to 4,000 gallons, jet/vac combination units, CCTV survey kit and confined space teams for pump station wet wells.
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Scores as of September 2026
★★★★★Our family have been using Clearmasters for years and are the only choice as far as we are concerned! All the staff are friendly, helpful and accommodating. Couldn’t recommend them highly enough!
Stu Google review
★★★★★I have used Clearmasters for years. They are always on time, polite and reliable whether your need them to empty your septic tank or undertake maintenance work. I wouldn’t use anyone else. Local and the best.
★★★★★Work carried out professionally as usual, the only company I'd recommend.
How it works
The same simple process whether it’s a yearly service or a one-off empty.
Step 1
Call us or book online and tell us what you have and when it was last emptied or serviced. If you don’t know whether it’s a septic tank, cesspit or treatment plant, we can help you work it out.
Step 2
We agree a date and send a tanker or a service engineer, depending on the job. 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 about your system and we’ll come back with a price for emptying, servicing or a survey. If it’s overflowing, call us instead.
Questions answered
The questions people around Winchester ask us most about their private drainage.
At least once a year, and most makers recommend it. Most plants also need the sludge emptying every year or so, depending on the size of the plant and how many people use it. We can do both on the same visit.
Yes. Under the General Binding Rules, a septic tank that discharges straight into a ditch, stream or river must be upgraded, usually by fitting a treatment plant or moving the discharge to a drainage field. You can read the rules on GOV.UK, and a septic tank survey will tell you where your system stands.
It can. Chalk usually drains well, so soakaways often work, but the groundwater under it is used for drinking water. That’s why the rules are tighter close to some water sources. If you’re planning a new soakaway or drainage field, check whether you need a permit first.
Councils in the Itchen and Test catchments ask new housing to show it won’t add to nutrient levels in the Solent. If your new home won’t be on mains drainage, that affects the type of treatment plant you choose and may mean extra mitigation. Speak to the council early; we can then install and service the plant you need.
Find out what kind of system it is, where it discharges, when it was last emptied and whether there are any service records. A survey before you exchange answers all of that and tells you whether any upgrade work is likely.
We have tankers and engineers working across Hampshire most days, so we’re rarely far away. If you have an emergency, call 03333 233566 at any time and we’ll tell you when we can be with you.
Got a different question? Call 03333 233566 or send us a message.
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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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