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Borehole septic

A guide to Boreholes & other Discharges to Ground

A look at the different methods used to discharge residential sewage to the ground. Including Boreholes, Crates and Tunnels.  To arrange a free quotation please call us on 0800 3101092 or via our contact form.

What is a Discharge to Ground?

When looking at residential off main foul water systems there are two classifications of discharge. These two classifications are to surface water and to ground. Surface Waters include rivers, streams, estuaries, lakes, canals, or coastal waters. To Ground is literally just that, into the soil, we will explore the main methods in the article below. 


What are the different ways to discharge to the ground?

We often get asked for the definitions of the different methods used to discharge to ground and how each interacts with the Environment Agencies General Binding Rules. A discharge to the ground has to be made from an approved Septic Tank or Packaged Sewage Treatment Plant. 

The main terms used and explored in this article are:

I would recommend you read our soakaway regulation page as well. This gives more background and detail on the current regulations concerning discharges to the ground.

Boreholes used as a Discharge to ground

What is a Borehole?

A Borehole is effectively a narrow shaft drilled vertically into the ground. The shaft is generally over 3m in depth. This shaft is lined with a thin casing up to a specified depth, this then changes to a permeable filling such as 20mm shingle.

How are Boreholes used in Septic Systems?

For the purpose of off mains drainage, the shaft is to allow for the dispersal of the discharge from your Septic Tank or Sewage Treatment Plant. The reason this solution is used is generally to bypass an impermeable geological strata, normally heavy clay.

Do we recommend the use of Boreholes?

We do not recommend or support the use of Boreholes. The reason for this is that they are expensive, difficult to maintain or repair and represent a single point of failure. Obtaining a Permit for their use is also difficult.

Do you need a Permit for using a Borehole to discharge sewage discharge?

A borehole is not compatible with the General Binding Rules. As such the Environment Agency require you to apply for a Permit to discharge. For small sewage discharges, this is called a B6.5 permit. We have heard from customers and tank manufacturers that the Environment Agency is increasingly refusing permits for this type of solution.

As a warning, we have also heard that rogue companies are telling customers that they need to apply for this permit themselves and that these are easy to obtain. If a company is not willing to apply for a permit on your behalf for their own work, say no.

The reason the Environment Agency does not like Borehole’s is because of their depth. A borehole bypasses strata of soil, which act as filtration and can discharge directly to Ground Water. Ground Water is used for drinking water etc. Thereby discharging sewage discharge directly into drinking water sources is not considered desirable. In fact, Boreholes are most often used to supply off-grid properties with water. It does not take much common sense to see why the EA takes issue with this type of discharge.

Tunnels used as a Discharge to Ground

What are Tunnels in the context of off mains drainage?

A tunnel is a plastic casing that creates a void in the ground. Sewage discharge enters and then disperses. The use of Tunnels currently always requires a permit. For more information, please see our guide.

Crates used as a Discharge to Ground

What are crates used for with Septic Tanks?

When a company mentions they will use crates as your discharge this refers to the use of rainwater crates. Please see the picture below. In a similar way to tunnels, a crate creates a void in the ground that the discharge enters and then trickles out into the surrounding ground.

Do you need a Permit for using Crates to discharge sewage discharge?

The use of crates is not compatible with the General Binding Rules. As such the Environment Agency require you to apply for a Permit to discharge. For small sewage discharges, this is called a B6.5 permit. If a company says they will self-certify or tells you a permit is not required then simply they are lying or incompetent.

Rainwater crate
Rainwater crate in action

Soakaways used as a Discharge to Ground

What is a Soakaway?

When a company mentions they will use a Soakaway they normally mean a pit in the ground of undefined size and depth that is filled with rubble or stone. The Sewage Treatment Plant or Septic Tank then discharges into this pit. The discharge disperses into the surrounding soil.

Do you need a Permit for using a Soakaway to discharge sewage discharge?

The use of a soakaway is not compatible with the General Binding Rules. As such the Environment Agency require you to apply for a Permit to discharge. For small sewage discharges, this is called a B6.5 permit. Please see our blog on the difference between a soakaway and a Drainage Field.

Drainage Fields used as a Discharge to Ground

A Drainage Field is the only new or replacement discharge to ground that is allowed without a permit under the General Binding Rules. Please see the following article to get an understanding of what one is and what you need to do to install one.

Want to learn more?

We have a large collection of articles containing the answer to all of your questions. Check out our Blog Page 

Our Core Services: The Sewage Treatment expert Installers

On the 1st January 2020, all Septic Tanks that discharge to a Stream, Watercourse or Drainage Ditch will become illegal and will require replacing with a Sewage Treatment Plant. Please see here for more details.

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Expert wastewater treatment engineers who specialise in Septic Tank and Soakaway replacements as well as Sewage Treatment Installations. We are based in the New Forest, Hampshire but operate across the South Coast as well as Wiltshire, Somerset, Devon, Sussex, Surrey, Oxfordshire, and Berkshire.

The Home of Septic tank and private drainage system solutions. 

Based in the New Forest, Hampshire on the border with Dorset and Wiltshire we operate an expert team of off-mains drainage specialists. This encompasses Septic Tank, Soakaway and drainage system problems, installations, blockages, and servicing. In addition, any issues relating to cesspits and sewage treatment plants.

Homeseptic offers high quality, professional advice, repairs and installation for all aspects of effluent cleansing and disposal across the south of England. Whether you’re looking for septic tank installation, sewerage treatment plants or systems, piping or soakaway solutions, Homeseptic employs only the most competent engineers in the drainage and treatment industry and knows exactly which solutions suit each property.

We only install and offer quality systems we believe in, from suppliers we know and trust.

New Forest Philosophy

As we have said Homeseptic is based in the New Forest. A great location in between the cities of Southampton, Salisbury and Bournemouth. We are a group of good friends who grew up together in the area.  Individually we all have grown tired of the way other Drainage firms are run. As a result, this is why we set up Homeseptic. If you want to know more please check out our About Page

We want to actually put the customer first and turn up to do a great job that we can be proud of. Unfortunately, this is not the case in the market, with most companies pressuring their workers to sell unnecessary works on a visit. Due to this, we offer upfront quotations with any variations discussed before we start work.

We are honest hard working professionals, which we hope you will agree with. As a result, it will certainly not turn up in flash sales vehicles and give you a load of chat and then do a terrible job. Our team will come with the job in mind and the aim of giving you the best value we can in order to facilitate a quality installation. 

We cover all of Hampshire, West Sussex, Dorset, Somerset, and Wiltshire. Please get in touch and see what you think.

Learn more about Borholes
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Learn more about Borholes
A guide for anyone looking to use boreholes instead of a drainage field.
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