Septic Tank Conversion

Is your septic tank working properly? Is water sitting in the drains, backing up towards your house causing blockages and unpleasant odours?

Perhaps a septic tank upgrade is in order!

The Allerton ConSept

The Allerton ConSept is the ideal solution for your septic tank conversion. The Allerton ConSept will convert your existing septic tank or cesspool into a fully functional sewage treatment system producing a final effluent that can be discharged into a watercourse or soakaway.

Please note that discharge to watercourse or soakaway is subject to consent from the relevant authorities. However, we can help with the Environment Agency permit.

The Allerton ConSept

The Allerton ConSept is the ideal solution for your septic tank conversion. The Allerton ConSept will convert your existing septic tank or cesspool into a fully functional sewage treatment system producing a final effluent that can be discharged into a watercourse or soakaway.

Please note that discharge to watercourse or soakaway is subject to consent from the relevant authorities. However, we can help with the Environment Agency permit.

What are our customers saying?

"We were really impressed with the work and the installation. Every member of the company with whom we had contact were really professional, very helpful, and very friendly. The work was done within a day, the garden was left tidy, the installation is really unobtrusive. We are so pleased with it, and now we are conforming to the 2020 General Binding Rules which is nice."
Mr and Mrs Gulliver
ConSept Installation in Walkerith

We are one of the most highly reviewed UK company in off-mains drainage. Read our more than 65 positive reviews.

Why Use The Allerton Consept?

Our customers are at the heart of everything we do. We understand you will have a lot of questions and concerns and we will give advice freely.  We have a 2 year warranty on all working parts, and at the end of the installation you will have a Binding Rules compliant sewage treatment system. You will also be left with a clean and tidy garden as per the pictures below.

A trench is dug to connect the cable for the ConSept to the Isolator Switch

The ConSept is placed into the existing septic tank and connected with cables.

The soil and grass is replaced at the end of the job, leaving the garden clean and tidy.

The Allerton ConSept utilises your existing septic tank so that there is no need for heavy diggers and new units. Just spade work! Plus, it's quick to install which saves you time, money and disruption.

No moving parts inside the tank.

Installation within your existing septic tank means the Allerton ConSept cannot be seen or heard. However, the air blower remains outside the septic tank for easy maintenance.

Maintains water at correct level, keeping drains clear right up to the house.

Manufactured using high grade composite materials and non ferrous components means the Allerton ConSept does not corrode. This results in a long and trouble free life.

Aerobic process reducing smell and odours.

Low maintenance costs - Servicing once a year, desludging and emptying once every two years, Installation, Septic Tank Conversion Unit Servicing and Maintenance available.

Discharge to watercourse with permissions or to a soakaway.

Installation and commissioning by our British Water Accredited engineers included in package.

How Does It Work?

The raw sewage enters the septic tank which will become the aeration zone. Air blown from the Blower causes agitation in this area and breaks ups solids.

The Allerton ConSept is an aerobic treatment system and the bubbling air encourages the growth of aerobic bacteria. This is a huge improvement on traditional septic tanks which are anaerobic.

The space in the Allerton ConSept acts as a settlement zone, allowing fine solids to settle out. The treated effluent is lifted to the shallow sample chamber by syphonic action. From here the water can directly go to a water course, providing you have a permit from the environment agency.

Alternatively, the water can go into the existing soakaway as it now has a head of water to push it along the pipe and upwards into the top soil. From here it finds its way sideways and downwards.

The plug in the outlet pipe prevents water in the ground getting into the septic tank and manholes near the house. It separates the house from any groundwater so your drains will remain clear.

Allerton Septic tank conversion illustration, lincolnshire sewage treatment
ConSept in a GRP Septic Tank
Allerton Septic tank conversion illustration, lincolnshire sewage treatment
ConSept in a Brick Built Septic Tank
Cesspool convert to sewage treatment plant
We Also Convert Cesspools!

Recently we converted this 8000 litre tank to pump stormwater away.

ConSept Dimensions

ConSept diagram in GRP septic tank
GRP Septic Tank
dimensions consept2
GRP Septic Tank
ConSept septic tank conversion dimensions
Brick Built Septic Tank
Septic Tank Converter (ConSept) Dimensions
240v power supply
Air blower in kiosk
Inlet pipe
Sample chamber
GRP septic tank (first image) brick built tank (second image)
Outlet pipe to watercourse or drainage field

Population Equivalent

The population equivalent is 1-6. At Allerton we use a calculation for all of our units which is based on British Water guidelines to determine the appropriate size of the unit for the property. The calculation is known as the Population Equivalent (Pe) and it is a rating system that allows information to be comparable between different makes and models of units.

Learn more about Septic Tank Conversions

A conversion of a septic tank, a cesspool, a well, or some other underground tank to a sewage treatment plant.

NO. But you do if you decide to outfall it into a ditch.

Immediately, and you can use both shower and washing machine later in the day.

ConSept in a GRP tank, once every 2 years but in a brick tank better to empty every year. Discuss with the Service Engineer. He is in a better place to make judgement.

Bleach can be used in moderate amounts. The unit should not smell like a ST and bleach in excess is not needed. A cap full per week should be enough, preferably not all on one day.

Allerton ConSept brochure septic tank conversion
Read the Allerton ConSept Specification Documentation
Why Allerton?

Why Allerton?

Qualified

All units come with a 2 year warranty on all working parts. Allerton offer servicing of the units and other manufacturers’ units so you can always rest assured your treatment system is receiving the best care.

Value for Money

We offer a free initial on-site consultation for installations within a reasonable distance from Sleaford. We keep our customers in mind when it comes to pricing. We have saved our customers hundreds of pounds over the years by our considered overview. We can do the same for you! Speak to us for a quote!

Friendly

Allerton offers a unique level of service drawing on 50 years of experience we can help with sizing your treatment system, installation advice and offer a full installation service.

Ready to arrange an appointment?

Contact our office to arrange a visit. Don’t hesitate to talk to us if you have any questions or concerns.

Carrie ArmitageCarrie Armitage
05:11 28 Aug 24
Allerton's work installing a new domestic sewage treatment plant was first rate. From the initial visit and quote through to the installation everything was prompt, efficient, friendly and lived up to all promises and expectations. The installation team were great to work with, and despite some interesting old drainage issues when excavating the new location and decommissioning the old septic tank, they maintained their good humour and professionalism throughout. I can highly recommend their services. Thank you.
Lisa DavidsonLisa Davidson
05:27 23 Aug 24
Excellent system and the engineer (Dayton) who carried out our annual service recently is clearly very skilled, taking the time to explain things to us and ensuring the septic tank was working correctly, he also enjoys his job which is refreshing to see. The tank still doesn't need emptying after 3 years, very satisfied!
mark quigleymark quigley
10:46 16 Aug 24
Excellent service, great communication and lovely people to deal with.I first wrote this review 3 years ago and they have consistently delivered excellent service since then. Very friendly and professional
Malcolm HarringtonMalcolm Harrington
16:36 02 Aug 24
The Allerton team were excellent. Their work was excellent and their great attitude a credit to them and Allerton.I recommend them highly.
Catherine WhitallCatherine Whitall
15:01 26 Jul 24
Many thanks to Allerton Bradley and especially Jason, Chris, James, Aaron and the team for a top rate service from start to finish. Had a new Diamond DMS3 water treatment plant installed to replace our old septic tank. Extremely professional installation, great communication throughout from the guys on site and the office, tidy, punctual and a fantastic end result. I would say I'm not the easiest to work for, have very high standards, know exactly the job i want done, do not employ many companies as prefer to carry out most jobs myself, however it was a pleasure having these guys on site. Would not hesitate to recommend. Oh and its great to be able to use the loo's etc whenever needed rather than going to the local garden center to use their facilities!!! Many Thanks, Graham & Catherine
Shelley WilliamsShelley Williams
07:14 01 May 24
Cannot recommend Allertons enough! Excellent service with speedy attendance by an engineer and the problem of a faulty timer was resolved without being too costly! Will definitely be saving their contact number on speed dial!
Paul ScottPaul Scott
15:20 22 Apr 24
We have used Allerton to maintain our household pump system for several years. Always found their staff pleasant and helpful. Last weekend a fault developed which we reported on the Monday morning. By Monday afternoon they had called, identified the fault, offered advice, made the repair and everything left tidy and all with a smile.
Cherie PearsonCherie Pearson
16:12 16 Apr 24
Great service, good to receive email reminder when service is due!Very pleasant person arrived promptly to do the service.
harriette Bradleyharriette Bradley
15:44 01 Apr 24
Fantastic service from Allerton. Chris was brilliant! He was punctual, polite and professional. The finish was outstanding. We are so pleased with the result. Would definitely recommend Allerton and Chris. Thank you so much.
Nigel SellersNigel Sellers
10:40 12 Jan 24
Living close to one of Hampshire's best chalk stream rivers, having the right treatment plant that is compliant and meets with the EA's stringent regulations is a necessity. Our old cesspit did not meet with the latest regulations so when we looked into changing to a sewage treatment plant Allerton gave us the reassurance and expert knowledge that we needed. The treatment plant has been installed for over a year now and we have just had our annual service. The team at Allerton are all knowledgeable, professional, helpful and courteous when ever I have needed to contact them, nothing is too much trouble. I would recommend the company and specially if you live close to a river where specialist advice is needed when considering the options of changing from a septic tank arrangement to a compliant treatment plant.
David Le SueurDavid Le Sueur
14:17 11 Jan 24
Alerton is a reliable company that thrives on clear customer contact, providing us with a no nonsense practical service that is invaluable and most necessary.Allerton personnel are pleasant, informed and helpful. We have used the company for years and intend to stay with them.Thank you Allerton for your immaculate service.
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