Do you need planning permission for a sewage treatment plant?
Replacing a septic tank is usually permitted development, but building regulations still apply and some sites need consent. Here is what applies when.
Read the guideVariable occupancy, farmyard waste and multiple buildings all change how an off-mains system behaves. What catches farms and holiday lets out.
The problem on farms and holiday lets is rarely the tank itself — it is the load. Occupancy that swings from empty to full, several buildings on one system, and yard water finding its way into the foul drain all push a system past what it was sized for. Size for the peak, keep surface water out, and empty more often than a house would.
A domestic system serves a fairly predictable load: the same handful of people, every day, year round. Farms, smallholdings, holiday lets and rural businesses break every part of that assumption. The load swings, the mix of what goes in changes, and the system often grew piecemeal as buildings were added.
That is why the same tank that behaves perfectly on a four bedroom house gives endless trouble on a farm — not because it is a worse tank, but because it is being asked to do a different job.
A holiday cottage that sleeps eight is empty midweek in February and full every night in August. A septic tank copes with this reasonably well; a sewage treatment plant does not, because its bacteria need feeding. Long empty periods starve the biology, and then a full house arrives and overwhelms what is left of it. The result is poor treatment for the first week or two of every season, and often a smell to go with it.
The practical answers are to size for the peak rather than the average, to choose a plant that tolerates variable load if a plant is needed, and to service it at the right point in the year — before the season starts, not in the middle of it.
For any property that is let, the sizing is based on how many people the building can hold, not how many are usually there. A let that sleeps ten is a ten-person load even if it averages four. Undersized systems on lets are extremely common, and no amount of maintenance fixes an undersized system.
The single most common fault we find on farms is surface water in the foul system. A yard gully, a roof downpipe from a barn, or a drain in a hard standing connected into the foul run will put more water through the tank in one storm than the house uses in a fortnight. Solids get flushed straight through to the drainage field, and the field does not survive that treatment for long.
It is usually historic — something connected decades ago when the yard was re-laid — and it is invisible until someone traces the drains. If a system only misbehaves in wet weather, this is the first thing to look for.
Farm systems see things domestic systems do not, and some of them will finish a tank off:
Farm and yard waste streams need separating from domestic foul drainage, with interceptors where appropriate. Mixing them is how a tank that should last decades fails in a few years.
Plenty of farms run the farmhouse, a converted barn, a let cottage and a office or workshop into one old tank that was installed for the farmhouse alone. That system is overloaded by definition, and when it fails everyone is affected at once. It is worth establishing what is actually connected before deciding what to do — we trace the runs and map them, and more often than not something is connected that nobody knew about.
Where several dwellings share a system, the maintenance arrangement matters too: who empties it, who pays, and who is responsible when it fails. Getting that written down saves a great deal of difficulty later, particularly if any of the properties are sold.
We work on farms, smallholdings, holiday parks, pubs and rural businesses throughout Derbyshire, the Peak District, Sheffield and north Nottinghamshire, with our own tankers, jetting and camera kit, and we can put a site on a scheduled contract so nothing is left to memory. Call 07884 111 641.
Commonly before and after the main season, and more often if it is busy year round. The useful approach is to have it emptied and inspected once, then set the interval from what is actually in there.
It can if it is sized for the combined load and the drainage field is sized to match. The problem is systems that acquired extra buildings over the years without being upgraded.
Dairy washings, silage effluent and yard runoff are separate waste streams with their own requirements — they should not go into a domestic septic tank or treatment plant. We can advise on separating them and on interceptors.
Yes. Scheduled emptying, servicing and jetting with the paperwork handled, so records are there when a buyer, an inspector or an insurer asks.
Septic tank emptying, installations, servicing and drainage across Derbyshire, Sheffield and Yorkshire — 24/7.
Replacing a septic tank is usually permitted development, but building regulations still apply and some sites need consent. Here is what applies when.
Read the guideRoots find old clay joints, thicken into a mass and catch everything passing. Jetting clears them; unless the joint is repaired they come back.
Read the guideA percolation test measures how fast your soil accepts water, and that single figure sets the size of your drainage field — or rules one out entirely.
Read the guide