Plain-English guide
The septic tank rules, explained without the jargon
If your Shropshire property has a septic tank, treatment plant or cesspit, a set of Environment Agency rules called the General Binding Rules applies to you. Most owners first hear about them during a house sale, usually at the worst possible moment. Here is what they actually say.
The rules in one paragraph
The General Binding Rules govern small sewage discharges in England, which covers almost every domestic septic tank and package treatment plant. If your system meets the rules, you do not need an environmental permit. If it does not, you must either bring it into line or apply for a permit, and for an ordinary house the practical answer is nearly always to bring it into line.
The big change: no septic tank discharge to a watercourse
The change that catches people out arrived on 1 January 2020. Since that date, a septic tank may not discharge to surface water: no pipe to a stream, brook, river, canal or ditch. A septic tank only settles solids out of the waste; the liquid that leaves it is still polluting, and the rules now insist it goes into the ground through a properly constructed drainage field, where the soil finishes the treatment.
Plenty of older Shropshire systems were built exactly the way the rules now prohibit. Piping the tank outfall to the nearest ditch was normal practice for decades, and in a county laced with brooks, drains and field ditches, there was usually one close by. If your tank still discharges that way, the arrangement is non-compliant today, not just when you come to sell.
Your options if you are affected
There are three recognised fixes, and which one suits your property depends mostly on your ground and your budget:
- Install a sewage treatment plant. A treatment plant cleans the waste to a much higher standard, and treated effluent from a plant is allowed to discharge to a watercourse. On the heavy clays common across north Shropshire, where drainage fields struggle, this is often the only practical route.
- Install a drainage field. Keep the septic tank but send its outflow into a drainage field built to British Standard BS 6297, sized from a percolation test. This needs ground that actually drains and enough space at the required separations from buildings, boundaries, wells and watercourses.
- Connect to the mains sewer. The cleanest fix of all, but only realistic where a public sewer runs close enough, which in rural Shropshire it usually does not.
The other rules worth knowing
- Volume limits. Without a permit you may discharge up to 2 cubic metres a day to ground, or up to 5 cubic metres a day to surface water from a treatment plant. Ordinary households sit well inside these limits; large properties, holiday complexes and businesses may not.
- Equipment standards. New treatment plants must be certified to the European standard EN 12566-3, and new drainage fields designed and built to BS 6297.
- Maintenance is mandatory, not optional. Systems must be maintained in line with the manufacturer instructions, emptied when they need it by a registered waste carrier, and fixed promptly when something fails.
- Siting rules for new systems. New discharges have additional requirements covering distance from water supplies, wells, watercourses and buildings, and groundwater protection zones. This is design work we handle as part of any installation.
- Building regulations and planning. Installing or substantially altering a system involves building regulations approval, handled locally through Shropshire Council or Telford and Wrekin Council depending on where you are.
Buying or selling a rural home
This is where the rules bite hardest in practice. Conveyancing solicitors now ask detailed questions about off-mains drainage, and a non-compliant system discovered mid-sale becomes a negotiation over who pays for the fix, with the clock running. Sellers do better by getting the system inspected and, if needed, upgraded before listing. Buyers do better by commissioning a proper survey of the tank and drains before exchange, so any upgrade cost is priced into the deal rather than discovered after completion.
We carry out pre-sale and pre-purchase inspections across Shropshire, and the upgrade work that follows when a system falls short.
Where to check the official wording
This guide is a plain-English summary, not legal advice. The authoritative source is the government guidance on small sewage discharges, published at gov.uk. If you are unsure how the rules apply to your property, ask us: assessing systems against the rules is everyday work for us, and an honest assessment costs far less than a mid-sale surprise.
Common questions about the rules
My septic tank discharges to a ditch that is dry most of the year. Am I affected?
Usually yes. A ditch that carries water at any point in the year is generally treated as a watercourse, so a septic tank discharging to it falls under the ban. The safest course is to get the arrangement assessed rather than assume a dry summer ditch does not count.
Is there a grant for upgrading a septic tank?
There is no general national grant scheme for septic tank upgrades. The cost normally falls to the property owner, which is why compliance so often becomes a point of negotiation in a house sale.
Who enforces these rules?
The Environment Agency. In practice, issues most often come to light through pollution reports or during conveyancing, but the rules apply at all times, not just when someone is looking.
Does a compliant system still need maintenance?
Yes, and maintenance is itself part of the rules. Tanks must be emptied by a registered waste carrier at the intervals the system needs, treatment plants must be serviced in line with the manufacturer instructions, and keeping records of both is strongly advisable.
Not sure if your system complies?
We will assess it, explain your position in plain English, and quote for any work needed. No scare tactics, no obligation.