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  • Sarah


In the spirit of this website being about off-the-beaten-path travel and exploring the places that no one else goes, today I went on a free Round the Bend tour in Tisbury, Wiltshire, run by Wessex Water, one of several they do across the region. It really is a way to see something unusual, different and unique and I can guarantee that no-one you know will have done this tour.

Posters of famous art works with loo rolls added in
There is a humorous art display with a watery theme in the 'Loovre'

Wessex Water are the suppliers of water for much of the south-west of the UK covering parts of Wiltshire, Dorset and Somerset. Water is something that we very much take for granted in the UK - it arrives on demand and is taken away without a moment's thought, only reaching our awareness when our drains are blocked with a 'fatberg' or we wrinkle our noses in disgust at the huge round vats of brown looking sludge that we may briefly see on train journeys.

These vats are where sewage is processed and are the locations for the Round the Bend tours. They are actually far less disgusting that I had thought (the brown sludge you see is not sewage, it is rocks) and the whole process of cleaning the sewage is an organic and natural one, mostly fully automated with no chemicals involved.

The tours are run by Wessex Water to try to educate people about what they do, how the system works and to give people a chance to ask questions. You can find the tours on Eventbrite - they are completely free and although they haven't run for a few years, I believe it is something they are planning to do more regularly.

I joined a tour in Tisbury, about 14 miles west of Salisbury, and was thankful that the ticket included a what3words locations, as by their very nature, the sewage treatment plants (officially called Water Recycling Centres) are out of towns and in discreet locations. The plants do not have their own staff as the system is automated, but there were lots of staff on hand for the tours, cheerful people in blue hi-viz who helped with parking and did the tours. There was a display put on while we waited for our tour - art work re-imagined with a specific watery theme, and also a quick demonstration.

A pump over a skip
The first stage of filtration

A piece of loo roll was put into one bottle of water and shaken about. A 'flushable' wet wipe was put into another bottle of water and shaken about.

As you can imagine, the toilet roll disintegrated entirely in the water and the wet wipe remained completely intact. It makes it easy to understand why water boards hate these wipes so much as they are the cause of so many blockages and expense, but it is mind-boggling that the manufacturers are allowed to declare these things 'flushable' when they clearly are not.

The tour started at the initial pump, where all of the pipes come in from the catchment area and everything is filtered through screens, with all the big bits being taken out, washed, chopped and dried. These include rags, grit, bits of wood - our guide said there have been false teeth and all sorts of random objects appearing at this stage. These items were all in a small skip, drying out quietly in the sunshine.

Then we moved onto the large round tanks. The first of these - the primary settlement tank - had a thick layer of scum on the top which was being scooped up by the rotating arms. In here, the sludge sinks to the bottom and is pumped to a large, sealed tank which is emptied about twice a week, the sludge going off in lorries for treatment at one of their larger plants which may then end up on farmers' fields. The remaining water is pushed over the sides. Our guide showed us a bottle of the water at this stage - rather murky with a few floating particles.

The water that has gone over the sides then moves to one of several other large round tanks which I had always thought were full of human waste. These are the ones you see filled with brown stuff, rotating arms going round sprinkling water on them and birds flocking above them. All of us in the group were astonished to learn that the 'brown stuff' is in fact pumice rocks.

Bacteria lives in these rocks - they move in naturally over time - and it is these which filter the water by feeding on the pollutants. The sewage is actually the water from the first tank, which is being sprinkled on top by the rotating arms, moving through the rocks and being filtered. The whole system is run by hydraulics and the power of the water - no electrics involved. The rocks were covered in moss, and a flock of wagtails were helping themselves to the varied insect life which lives there. It is a completely natural and organic filtration system. We were shown another bottle of the water at this stage - mostly clear with just a few tiny particles suspended within.

Duckweed at the top of a large sewage tank
The water is so clean by this stage that duckweed grows on it

The water then moves downhill to another of the round tanks. This one is just full of water, again with a rotating arm and again the water goes over the sides with the tiny remaining bits of sediment going to the bottom of the tank. The water is so clean at this stage that there is duckweed growing on it, and the sample bottle we were shown was crystal clear. The water is then pumped to four large tanks which are filled with sand which is kept constantly moving and which takes out the very last of any remaining sediment.

From here the water goes through a final pump and ends up in the River Nadder, often cleaner than the water which is already in there. None of this water is used as drinking water. Everything is carefully regulated and checked by the Environment Agency who set the standards for the water quality.

The sewage works at Tisbury
After the final filtration the water heads off to the four upright tanks which are filled with sand

The sites are fully automatic and run without any people having to be involved. They are monitored 24/7 by lots of sensors and the minute there is a problem, the Wessex Water engineers are sent out, even in the middle of the night, to fix it. The whole filtration system takes about a day from flush to river, although it can vary.

In Tisbury there is not much industry or many restaurants, so everything that comes in is quite clear anyway. In cities, towns and industrial sites, they may suffer from what is called FOG (fat oil and grease) buildup. Our guide explained that in the nearby town of Shaftesbury which has a lot of restaurants, they had quite a problem with FOG. They dealt with it by educating the restaurants to use grease traps rather than just tip everything down the sink, and the problem was soon resolved.

Tour groups on the Round the Bend tour
There were lots of tour groups being shown around - it was clearly a very popular tour

Our tour guide was bombarded with questions from the group throughout the tour and he answered them all very patiently and with much enthusiasm for the subject matter. We were all talking to each other too, mostly about how we'd had no idea that's how it all worked, how little it smelled when we'd expected it to be terrible and how impressed we were that the system was organic and natural.

A man holding a bottle of water in front of a tour group
Showing our group the condition of the water only part of the way through the filtration process

After just an hour I was back in my car driving through the leafy lanes of rural Tisbury and thinking how surprised I was that I had found it so interesting. I had learnt a lot, been surrounded by greenery, wildlife and the river and met some interesting people - you can't ask for more than that for a free tour.

So if you want to really get to the bottom of a place and visit somewhere that very few other people have been, you will not be disappointed by a Round the Bend tour!


Booking a Round the Bend Tour

Keep an eye on the Wessex Water events page to see upcoming events. They don't just do the Round the Bend tours - some of their sites have open days too which do not have to be booked in advance.

You can book the free tours through Wessex Water on Eventbrite - they are held in various locations across the Wessex Water region. Other water boards may do similar tours - follow your local water board on Eventbrite to find out.

The tours are child friendly - there is a special trail for kids to follow along with. There is nothing inappropriate or unpleasant on the tours.


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