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Dorsets expert Septic Tank and Sewage Treatment Plant Installers.

We offer a Free quote for all installations please get in contact on 0800 3101092 or contact us here


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Dorset its areas of outstanding natural beauty, geology, and its relevance to septic wastewater systems:

Get in contact with us on 0800 3101092  or via our Contact Page

Dorset comprises no cities and comprises the unitary authorities of Christchurch, Bournemouth & Poole with 2 Areas of Outstanding Natural Beauty covering 53% of the county. The two areas of AONB are Cranborne Chase and the West Wiltshire Downs. Our head office is located within the Hampshire limits of Cranborne chase and we are used to dealing with both the geological and planning intricacies. In addition, there are many areas of special scientific interest.

The area covers a wide range of geology which challenges the installation and maintenance of septic tanks and notably their soakaways and drainage fields. Roughly 66% of the county is covered by chalk, clay or mixed sand and gravel. Chalk as long as not impermeable is good material for installing sewage treatment plants. Clay is problematic and proves difficult to drain and to dig in generally. We attend many jobs where inappropriate soakaways, both rainwater and foul, have been installed in clay and simply do not work.

As anyone familiar with the area knows the county also incorporates some of the best beaches and seascapes anywhere in the world. This combined with the several major river valleys provides their own unique challenges. These mainly relate to the groundwater level. For any installation, we will undertake an initial soil test or percolation test if required and we will be able to determine a level of risk. Again we have seen many competing sewage treatment plant installers incorrectly installing systems in the summer months which do not work in winter when the water level rises. Although biased I would say get a professional firm such as us in to avoid thousands of pounds of remedial work.

Septic Tank Surveys and inspections for those buying or selling a house in Dorset.

With the introduction of the General Binding Rules in 2015 and the 2020 ban on Septic Tanks being able to discharge directly to surface water, it has become standard practice for a survey to be required by mortgage companies and solicitors to assess any off-mains system. We offer a comprehensive investigation and report of any such system to both give you the confidence needed to buy your new property with confidence and to fulfill any legal or financing questions. If you are Buying or Selling a property with a Septic Tank, Sewage Treatment Plant or Cesspool/Cesspit then please have a look at the following links:

Home Sellers Septic Survey Dorset: This article illustrates the main reason to have a survey if you are selling a house.

Home Buyer Septic Survey Dorset: This article illustrates the main reason to have a survey if you are buying a new property.

Buying a house with a Septic tank, Cesspit, or sewage treatment plant: This is a great article for anyone either buying or selling a property that is not up to date with the new regulations.

Septic Tank Replacement & Installation Dorset:

Septic Tanks are simple devices, they offer a basic level of rudimental treatment. However as with everything it has a finite life span. The main cause of a septic tank failing is some form of structural failure which means the wastewater is no longer contained within the tank and it leaks out. This means even the basic level of treatment of the wastewater does not occur and effectively raw sewage seeps out into the ground. This leads to pollution occurring and the tank sitting outside of the General Binding Rules, which are set by the Environment Agency. The other main cause of a Septic Tank needing to be replaced is the 2020 change to legislation concerning Septic Tanks if they discharge to surface water. Essentially as of the 1st of January 2020 if you have a Septic tank that discharges to either a ditch, river, stream, pond, or lake you will need to replace it with a Sewage Treatment Plant. Please see our more detailed article for more information: Septic Tank Rules 2020.

Septic Tank Repair Dorset:

Can a Septic Tank be repaired? The answer to this depends on two main factors, the construction material used and the type and extent of the damage. There are two main types of construction materials, glass fibre, and brick & concrete. Modern fibre tanks are very difficult to repair if they lose structural integrity. In most cases, a replacement tank will be required. Brick & concrete tanks are easier to repair, the main factor here is the type of damage. A common situation with these types of tanks is where a wall begins to bow and crack due to the external pressure of the ground. In these situations, the tank will likely need replacing. If the leak or loss of integrity is caused by mortar having washed away then it is possible to repair the tank by repointing.

Septic Tank Problems Dorset:

The top 10 warning signs of Septic Tank Problems.

  • Slow flushing or in extreme cases an overflowing toilet.
  • Effluent or liquid surfacing around your septic tank, soakaway or drainage field.
  • If you’re discharging to a watercourse, a slow odorous discharge.
  • Movements in the ground in the vicinity of your system.
  • Horrible smells.
  • Gurgling or overflowing drains.
  • Septic tank problems after it rains
  • Problems with your washing machine, dishwasher, etc.
  • Your tank needs emptying more frequently.
  • Water collecting around your manholes.

If you are having problems with your Septic Tank then please head to our main Septic tank problems page: Septic Tank Problems – The signs and solutions

Soakaway Problems and Regulation Dorset:

If you have a Septic Tank or Sewage Treatment plant then it will need to discharge the treated wastewater somewhere. There are two options either to surface water or into the ground. If you discharge to the ground and your system was installed before 2007 it was likely to a soakaway. A soakaway is simply a hole in the ground normally filled with rubble. If your soakaway fails or you are installing a new system then an old-style soakaway is no longer an allowable option. The only solution now allowable without a permit from the Environment Agency is a Drainage Field. For more information please see the following page: Soakaway Regulations.

Septic Tank & Sewage Treatment Plant  Maintenance & Servicing Dorset.

Legally you have to have your tank serviced and emptied annually to comply with the General Binding Rules. The main reason that this is required is to ensure that your system is not working effectively and not causing pollution. We can help you here and offer a no-fuss annual servicing plan. Servicing & Maintenance page.

Towns of Dorset we cover for servicing, surveys, installation, and repair.


The charming village of Abbotsbury marks the centre of an area that has been settled for more than 6000 years. Within the present parish are over 20 tumuli or burial mounds, which indicate that there was a high population here from very early times. The undulating terrain leads and location on the Jurassic coast leads to several different septic tank installation challenges. The area has lots of sandstone, which as long as not mixed with water, running sand, makes installation feasible.  


Beaminster is an old settlement, dating back to around the 7th century, unfortunately, there is a lot of clay in the vicinity. I would advise against undertaking a DIY installation here or using the local farmer. Pay to get a professional into the septic tank and sewage treatment plant problems, especially with overflowing and blocked soakaways.

Blandford Forum

Blandford Forum was a major market town during the later medieval period. This was principally due to the fact that both the main road from Salisbury to Dorchester and that from Poole to Shaftesbury crossed the River Stour. The area of the river valley is obviously prone to water table issues. The higher areas of mainly chalk, as long as not impermeable provide good conditions for installations.


A coastal location with over 7 miles of golden beaches. Most of the area is connected to mains drains with some private drainage located in the larger properties on the edge of the town. We are happy to come in and quote, with a sewage pumping stations a favorite to transverse the distances to a mains drain connection.


Bridport is a small market town and fishing port, for many years the main producer of ropes in the country. It became a fortified burgh, established by Alfred the Great. The geology is mainly sand which can be good for draining but dangerous for excavating. Most tanks require excavation of c.3m, do not try to do this yourself, if, in a sand area, the sides will collapse!


During the Iron Age, the area between the rivers Avon and Stour were settled and the town of Christchurch was born. From Saxon times, the Great Priory Church occupied a prime position close to the river, dominating a timber-walled town arranged in a grid system. The geology of Christchurch is varied with groundwater level an obvious issue due to the river basins and coastal features.

Corfe & Kimmeridge

Corfe Castle is a village, civil parish and ruined castle with views stretching across the width of the Isle of Purbeck. The castle, which overlooks the village, commands a gap in the Purbeck hills between Wareham and Swanage and this important location has given rise to a long and colorful past, especially during the civil war. Conditions are generally good for the installation of new systems.

Dorchester is the county town of Dorset. The geology is mixed with mainly chalk in the north but several areas of very dense clay. Percolation tests are a must for this area. Make sure your engineer or contractor is carrying these out properly in line with building regulations to avoid costly mistakes.


Gillingham is the most northerly town in Dorset and comprises large areas of clay and hard stone. Installing a new Sewage treatment plant here is challenging. You must ensure that whoever you choose as your installer that they have carried out a proper percolation test and that you have a decent warranty from them.


West Lulworth and Lulworth Cove Situated between Weymouth and Swanage in south Dorset, Lulworth Cove represents one of the finest examples of a natural cove in the world. Recently incorporated into the UNESCO Jurassic Coast World Heritage Site. The protected status means discharges from a septic tank that requires permission will be difficult to obtain. Sewage treatment plants are the only choice. The regulation change taking place on the 1st of January 2020 means direct discharge from Septic Tanks will also become illegal.

Lyme Regis

Situated at the mouth of the River Lym, Lyme Regis is the most westerly town in Dorset. It lies halfway between Exeter, to the west, and Dorchester, to the east, and is known as “The Pearl of Dorset”. The geology is characterised by thick clay and thin layers of limestone. Many properties overcome the pore drainage potential of the geology by directly discharging to waterways. You must ensure that for any existing system using this method that you have a legally compliant domestic sewage treatment plant installed by the 1st of January 2020.

Milton Abbas

Milton Abbas, a charming and quaint thatch village sits on the Milton Abbey estate and is often featured on postcards showing rural Dorset at its most idyllic. The area is dominated by chalk, which if permeable can lead to a good installation.  


Dorset’s largest town and industrial centre is the old port of Poole, which boasts one of the largest natural harbours in the world. The low lying water dominated area raises water level concerns, which need to be expertly assessed. Discharges are generally direct to a watercourse. This means you should check your system meets the effluent standards set by the environment agency. If in doubt we carry out effluent quality tests. If you have a Septic Tank you will have to replace it. All new installations will need to be a sewage treatment plant.


Portland is not really an island but is reached over a narrow causeway from Chesil Beach. It is a huge block of limestone, measuring 4.5 miles by 1.75 miles and rising to a height of 400 feet above sea level in the north. As such installation of a drainage field or soakaway is almost impossible. You will likely need a borehole or direct discharge to a waterway or drainage ditch. Please get in contact for more information.


Puddletown is a small crossroads village close to Dorchester that retains a magical sense of times past. Formerly called Piddletown, for its proximity to the River Piddle, legend has it that Queen Victoria insisted the name was changed before a state visit.


Purbeck is a district of Dorset that takes its name from the peninsula known locally as the ‘Isle of Purbeck’. This sixty square mile chunk of land jutting into the English Channel is bordered on three sides by water and, although not actually an island, has an insular character. Geology is mixed but there are large areas of chalk, much of which is impermeable and obviously Purbeck stone. Installations are challenging but not impossible.  


At over 750 feet above sea level, Shaftesbury is one of the highest towns in England. It was known as ‘Caer Palladur’ in Celtic times. The Saxons built a hilltop settlement here, because of the commanding position overlooking the surrounding area. There are large areas connected to mains drain but also many private systems on the outskirts. There are large areas of sandstone in the area. Location and particular geology is key in this area and requires expert guidance.


Sherborne has much to offer visitors and is one of the most beautiful towns in England. Situated on the Dorset and Somerset border it has excellent transport links making it a great centre from which to explore the Wessex area of Dorset and the neighbouring counties of Somerset and Wiltshire. The geology is dominated by thick layers of limestone which can severely impact the drainage of private waste water sewage systems.


Stalbridge stands in the Blackmore Vale, close to the Somerset border, and is Dorset’s smallest town. The long main street runs from the church to the 15th-century market cross. Large areas of impermeable stone restrict private drainage, surveying is essential before the design of a new system or soakaway.  

Sturminster Newton

Sturminster Newton is a pretty Dorset town, in the Stour farmlands, where there has been a market since 1272. It is situated in the beautiful Blackmore Vale, between Sherborne and Blandford Forum. There are several rivers in the area, the largest of which is the River Stour. These low lying areas are prone to water table and ground water issues in relation to wastewater management and drainage.


The town of Swanage is on the Isle Of Purbeck, a spur of land jutting out into the English Channel. The wide Swanage Bay gives good views to the Isle of Wight in good weather. To the north are chalk cliffs leading to Old Harry Rocks. Much of the area is on private drainage but due to the nature of the geology most private drainage systems drain directly to drainage ditches. This means any existing owners should check your system meets the effluent standards set by the environment agency. If in doubt we carry out effluent quality tests. If you have a Septic Tank you will have to replace it. All new installations will need to be a sewage treatment plant.

There was a Roman settlement at Wareham and the modern town has grown up over this. It is believed that the transport of that time took advantage of the various rivers in the area and the closeness to the natural harbour at Poole. Wareham lies between the Rivers Frome and Piddle. The low lying areas require a direct discharge, a soakaway will fail. You should familiarise yourself with the new regulations coming into force from the 1st of January 2020.  


Weymouth Bay has often been described as England’s Bay of Naples. It has something to offer everyone with golden sands, safe bathing and beautiful coastline scenery. The low lying water dominated area raises water level concerns, which need to be expertly assessed. Discharges are generally direct to a watercourse. This means you should check your system meets the effluent standards set by the environment agency. If in doubt we carry out effluent quality tests. If you have a Septic Tank you will have to replace it. All new installations will need to be a sewage treatment plant.


Wimborne lies on the River Stour. It was an old Saxon settlement and the foundation of the Wimborne Minster dates back to the beginning of the 8th century. These low lying areas are prone to the water table and ground water issues in relation to waste water management and drainage.

Our Core Services

Installation, Replacement, Servicing  & Surveys of Septic Tanks & Sewage Treatment Plants.

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Our Core Septic Tank services and Information

Septic Tank Installation uk

We are based in the New Forest, Hampshire but operate throughout  Hants, Dorset, Wiltshire, Somerset and Berkshire. We will venture further a field, just give us a call for the best value quote you will receive delivered by our expert engineers. Please go to our in depth Installation page.

Septic Tank Problems:

Give us a call we may be able to help you over the phone. Failing that for more complicated issues we can dispatch an engineer to investigate. Please check out our Problems page.


Legally you have to have your tank serviced annually and emptied to avoid any pollution. We can help you here and offer a no fuss annual servicing plan. Our Servicing & Maintenance page.


About us & Our Services

Homeseptic performs maintenance, repairs, and installation on all makes and kinds of Septic Tanks and Sewage Treatment Plants in Dorset. We also carry out all types of, private drainage, Soakaway and drainage field replacements for storm water, rainwater, and effluent. All of us grew up in the Forest on the edge of Dorset and love the area. We have all worked in the drainage industry for the last couple of decades but have grown frustrated at how other companies operate. This is why we formed Homeseptic. We want to do a good job at a sensible price and leave a job feeling good about the work we have done. We don’t want to over charge, we don’t want to be rushed and we don’t want to install a system we know will fail. 

You will find we will always endeavor to find an efficient solution to all your drainage requirements. Removing and treating foul waste from a property is crucial for safety, hygiene, your ability to sell your property in the future and to ensure you are complying with legislation. Therefore it is sensible to call in trained professionals for the installation of a treatment plant or septic tank or in fact any drainage work.

What does a waste treatment plant do?

A treatment plant processes waste to a far higher standard than a septic tank installation. It effectively combines the process of both an old Septic Tank and its drainage field. Effluence is typically clear between 96% and 98% pure water and can be offloaded into a ditch or watercourse. From the 1st of January 2020, no Septic Tank system can be discharged directly to a ditch or watercourse. Given the challenge with soil type, the water table and access many New Forest Properties currently discharge to a ditch or watercourse. If you are unsure give us a call and we will check your existing system.

Although standard treatment plants use gravity to operate some will require an additional pumping system. Again this is very common because of the unique challenges the Dorset geology offers particularly in areas with a high water table or clay type soils. The new regulation requires all owners of Septic tanks and Sewage Treatment plants to have annual services and effluent checks, this can prove crucial when coming to sell your property. Again get in contact if you have any questions.

Environmentally friendly Graf products:

Coming from the Forest we are keen environmentalists, which is why conditions allow we to offer Graf Tank products. These German engineered systems are ultra-environmentally friendly.

The Graf tanks are single-chambered injection moulded systems set up to be ultra environmentally conscious from production through to the output. They are also designed with no moving parts or mechanical elements making them reliable, less costly and easier to maintain. See the Graf page here.

  • Sustainability starts with the manufacturing, this type of tank tech normally requires 2.7 kWh per kg of plastic to produce, Graf has it down to between 0.38 and 0.5 kWh. Further, all heat generated by the process is recovered and used to heat the companies logistics buildings. All the materials used are 100% recyclable.
  • Electric usage is kept to a minimum, 46kWh per person per year for the One2Clean and 43kWh for the advanced, a 9w energy saving bulb uses 78kWh, normal sludge activated systems use 217kWh.
  • Both of the Graf systems only require one pumping process compared to three in normal systems, extending the life of the core air compressor and delivering the energy savings.
  • The unique way the system treats the waste minimises the level of sludge produced and generates market-leading odourless effluent quality. Graf claims this leads to a carbon footprint of 25% compared to conventional wastewater treatment systems.

Where on your property can the treatment plant be installed?

This depends largely on the layout of the property and Building Regulations from the Environment Agency. We will assess your site and work with you to find the best solution for your installation. Ultimately a site and system which you are happy with.

The Dorset Council District Council offers the following advice. To be honest it’s pretty unhelpful but gives you a starting place for further research.

If you are really geeky and want to get into the detail of the geology and drainage of Dorset then this is a great map


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