Business Clinic: Septic tank rules explained

Whether it’s a legal, tax, insurance, management or land issue, Farmers Weekly’s experts can help. Here, Angus Hudson of Carter Jonas advises on the rules around the approaching septic tanks deadline, which affects many rural properties.

Q. I thought the new rules relating to septic tanks didn’t apply to me but I’ve just been informed that they do. I have a single cottage with no other properties around it, currently let on an Assured Shorthold Tenancy (AST). Do I still have time to become compliant and, if so, what are my options? Who is responsible for covering the cost?

A. The new rules that you’re referring to are known as the General Binding Rules (GBRs), which arose from the Environmental Permitting Regulations 2014.

See also: Business clinic – can I convert dairy building to residential use?

GBRs now govern the use of septic tanks, and the key new rule that land and property owners currently need to be aware of require all septic tanks that discharge into a watercourse to be replaced; so this is the first thing you need to establish.

If your septic tank does discharge into a watercourse, it will need to be replaced by 1 January 2020.

However, if it discharges into a closed groundwater soakaway system, then you don’t need to take action at the moment.

Once you’ve confirmed that your system needs replacing, the next step is to consider the three options available to you and decide which best suits your circumstances.

The most obvious option to consider first is connection to a mains sewer, not least because, in certain circumstances, this will in fact be mandatory.

For a single dwelling such as yours, you will need to connect to a mains sewer if it’s situated within 30m of that sewer (for multiple properties, this distance increases proportionately, so if there are two dwellings, the relevant distance will be 60m, and so on).

If it is located more than 30m from a mains sewer, you have two options.

For isolated properties, the most feasible option will likely be to install a small sewage treatment plant compliant with BS EN 12566.

These systems produce cleaner water than existing septic tanks so can discharge straight into a watercourse, subject to both the plant and the watercourse meeting certain requirements.

If ground conditions allow, you could install a drainage field system, compliant with BS 6297:2007, which can take wastewater from an existing septic tank and disperse it safely into the ground without causing pollution.

Before installing a drainage field system, it would be advisable to undertake a full percolation test to ensure that the system will remain effective throughout the year.

In terms of financing any works required, by default this will fall to you as the owner of the property.

It is worth checking the terms of the AST though, as it is possible to transfer responsibility to tenants or users of the system by written agreement explaining what maintenance is required for GBR compliance.

If you proceed with installing a sewage treatment plant or soakaway system, please bear in mind that you will need to get approval from building regulations.

There are minimum distances required between, for example, a sewage treatment plant and a dwelling; a drainage field system and a watercourse; or a discharge point and a habitable property. Check these requirements in detail beforehand.

Planning permission may also be needed, depending on the new type of treatment system selected.

So, there’s lots still to consider, but if you’re bound by these new rules, you will need to take action now. 

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