In this week’s feature for Back In Time, Richard Birch looks at the history of drinking water in the city as South West Water prepares to open up some of its sites to the public.

ALL things considered, we are lucky to be here at all.

When you consider the millions, billions and trillions of bacteria, germs and other nasties that our ancestors were exposed to almost every time they consumed water, it's a minor miracle that anyone survived.

"There is a very good reason why life expectancies were so much lower a couple of hundred years ago," said Chris Rockey, South West Water's scientific and reporting manager. "You don't really want to think about the sort of things that may have been present in the water that they were consuming.

"There was a complete ignorance about the way diseases could be communicated, even down to simply boiling water before it was consumed. If you continue to drink water from sources which feature the waste of dozens of your neighbours, you are going to get ill, probably fatally."

South West Water is about to throw open the doors of the Pynes Water Treatment Works, near Cowley Bridge, as part of this year's heritage open days series. It sees the firm open up a number of important sites for public viewing and the significance of Pynes cannot be underestimated, created as it was in the wake of great tragedy.

"The decision to build Pynes came after cholera had claimed the lives of 440 people in the city," said Chris, "If you look at the population of Exeter at the time, proportionately almost every family will have been affected in some way. And it could all have been avoided with a little bit of knowledge about the way cholera was transmitted.

"People in the West Quarter of the city relied heavily on the River Exe for their drinking water which contained all manner of waste, human or otherwise. But they carried on using it even after cholera started claiming victims in 1832. The widespread belief was that it was carried in miasma, foul air, germs carried on the wind, but it was water-borne and most who died did not stand a chance.

"The Romans had the right idea almost 2,000 years before. They built bath houses and put systems in place to keep water supplies separate but for centuries after they left, no one really thought to do the same."

The good people of Exeter relied on springs and wells for water for many years with the first major addition to the system coming when Cathedral authorities began work on the underground passages in the 13th century.

The city's growing population, which doubled in the 17th century in the wake of growing affluence, necessitated improvements.

Richard Lowbridge, Ambrose Crowley and Jonathan Pryke were commissioned to build a new water engine to pump water into the city and it was created in the New Mill Leat with a further building created at the rear of the Guildhall for the water cistern – a planning condition of which was that the jail beneath the tank had to be maintained.

It was greatly restored towards the end of the 18th century by James Golsworthy with its wooden pipes replaced with cast iron. He continued to carry out further improvements but while efforts were being made to get more water into the city, little or no expense was being made with regard to treating it.

There's no evidence to suggest that Golsworthy's system was in any way at fault for the cholera epidemic which swept through Exeter with studies carried out by Dr Thomas Shapter, who mapped the addresses of the victims to chart the spread of the disease, suggesting the source was the leats of Shilhay, into which the effluent of North Street had flowed.

In opposition to the water monopoly which Golsworthy had created, which had already caused consternation amongst the city's water carriers whose livelihoods were threatened, influential citizens organised a competition to improve the water supply with a £70 prize for first place and a £30 prize for second.

Consequently, in 1833 the Exeter Water Company was formed which receives an Act of Parliament to create a new water supply.

Abstraction from the river Exe moves from Exe Street to Pynes Leat, where the risk of pollution is less. A new water engine is also built on the site of an old grist mill at Upton Pyne along with a reservoir at Danes Castle.

Golsworthy, after protracted negotiations, also sold his lease to the new water firm. A second water wheel was installed in 1841 with filters installed at Danes Castle for the first time in 1849. And since then it has been a steady programme of improvements and advancements which have reduced the risk of becoming ill through drinking water to almost zero.

Chris said: "It is incredible to witness the progress we have made in the water treatment process over the last 179 years. Visitors who sign up to our tour will gain an insight into our past, current and potential future treatment processes. The significance of the site, and others across the country, is immense. Improving the water supply saved lives, and some of those it saved will have gone on to be some of the most significant inventors, politicians, public figures of their era. Never underestimate the importance of clean water."

There are a limited number of places available for a tour of Pynes on Friday, September 9. It will start at 10am and last about two hours. To book places, contact South West Water's Communications Team on 01392 443020.

Free tours are also taking place at other sites – Mary Tavy hydro electric power station in West Dartmoor with tours between 10am and 4pm on Thursday, September 8, and Friday, September 9; and Brokenbury Waste Water Treatment Works in Churston, Torbay, with tours between 10am and 2pm on Friday and Saturday, September 9 and 10.

MELINE: Treating our water

1832: Cholera outbreak in Exeter – 440 people die. Influential citizens organised a competition to improve the city’s water supply.

1833: The Exeter Water Company is formed. Abstraction from the River Exe moves from Exe Street to Pynes Leat, where the risk of pollution was less. A new water engine is built on the site of an old grist mill at Upton Pyne along with a reservoir at Danes Castle.

1849: Filters are installed at Danes Castle for the first time.

1853: Settlement tanks constructed at Pynes site.

1856: Steam engine is built to pump water from Exe to the city.

Early 1900s: Sand filtration systems are introduced.

1920s: A rising population led to greater demand for water so pressure filters and chlorination were introduced at Pynes.

1930s: Lime added to the treatment process to limit the amount of lead dissolved from customers plumbing.

1940s and 50s: Chemically assisted clarification processes installed.

1960: Plans for new reservoir at Wimbleball. Chris Rockey said: “This is an example of how you always had to plan ahead. The reservoir was not actually completed until 1981. You always have to build things with a capacity to accommodate expansion for 30 to 40 years and you can’t suddenly change everything when new technology comes along. You have to be prepared to make major investment in stages and take advantage of the next evolution that may be available several years down the line.”

1964: Exeter City water undertaking is absorbed into the East Devon Water Board.

1989: Privatisation leads to creation of South West Water.

1995: Rapid gravity filtration system put in to replace the pressure filters that were installed in first half of the century.

2000: Plumbosolvency control process added. Plumbosolvency is the ability of a solvent, notably water, to dissolve lead.

2004-06: £9.2 million investment into processes to remove any naturally occurring and man made organic compounds that are sometimes present in the Exe, to increase capacity of works from 48 million litres a day to 60 million litres a day, and improvements to the disinfection and sludge processes.

Now: Several projects under way including plans to improve and restore the mires of Exmoor. Chris said: “The aim is to restore the natural balance in the mires and remove some of the agricultural run-off, improving the quality of water in the River Exe. If you take some of the health risks away at the source, then the processes of treating it are more environmentally friendly and cost-efficient.”