A Busted Flush – Part 1: The Folly of Water Privatisation 

In the game of poker a busted flush may refer to four cards of a suit followed by a card of a different suit. Such circumstances would arise when a string of clubs is broken by the appearance of, for example, the Queen of Hearts. In 1865 the Reverend Charles Dodgson, aka Lewis Carroll a mathematics tutor at Oxford, wrote ‘Alice’s Adventures in Wonderland’ commonly known as ‘Alice in Wonderland’ in which, as the ruler of Wonderland, the Queen of Hearts becomes a source of conflict. The Queen never actually executes anyone she sentences to death and her power lies in rhetoric, thus reinforcing the view that she is ‘devoid of moral substance’. The UK Water Services Regulation Authority (Ofwat), the body responsible for economic regulation of the privatised water and sewerage industry in England and Wales, recently determined that a privatised water company manipulated water samples and “deliberately misreported data for many years to avoid financial penalties.” This action led to members of its staff being convicted of obstructing data collection. In the first of two articles Chartered Engineers Professor Robert Jackson and Graham Olsen discuss the enormous threats to the natural environment posed by the privatised UK water industry which too appears ‘devoid of moral substance’.

Dwight D. Eisenhower, a five star General and 34th US President, once stated:  “What is important is seldom urgent, and what is urgent is seldom important”. Today, the urgency and importance of the task in hand relates to agents that knowingly pollute invaluable natural waters and in so doing flagrantly disregard the law. The benefits accrued to public health since the beginning of the 19th Century through advances in civil engineering have been ‘systematically dismantled’ through water privatisation. So a question to be posed is ‘did privatisation of the water industry deal the environment a busted flush?’ The term ‘busted flush’ may be attributed to a number of scenarios. As stated above it may refer to four cards of a suit followed by a card of a different suit. Alternatively it can refer to something or someone that began an action successfully but later failed, or to storm-water discharges permitted by a water company but which subsequently create havoc and pollution from a first flush event within a sewerage network.

There has been much recent publicity regarding the adverse nature of storm sewage discharges into UK watercourses that continue to be attributed to water companies’ sewerage networks and their wastewater treatment works. This begs a number of searching questions. Why is this the case in the UK in 2022? What is occurring more than 30 years after the introduction of legislation that created the privatised water companies and defined what they might be permitted to discharge under EU legislation now enshrined into UK law? Over many centuries human health has been intrinsically linked to advances in medicine and sanitary engineering so before any of the above questions can be answered it is prudent to examine the history of wastewater collection, conveyance and treatment.

It is estimated that the first sewers were constructed in ancient Rome around 500 BC when the city’s sanitation became well advanced compared to that of other ancient cities. At that time residents were served by an extensive water supply from a series of aqueducts, and from sanitation services provided by a complex system of sewers much like modern sewers that transported human sewage, flushed from latrines, into nearby rivers or streams. Over time, the Romans expanded the network of sewers that ran through the city and linked most of these to the Cloaca Maxima, Latin for Greatest Sewer, which emptied into the Tiber River. In the 1980’s a modern form of this system was replicated in a major UK city, Liverpool, through the introduction of the Mersey Estuary Pollution Alleviation Scheme (MEPAS) to protect a river with the second highest tidal range in Britain.

It was Liverpool in 1846 that introduced its own Sanitary Act which resulted in the appointment of the world’s first City Engineer and the first purpose-designed comprehensive sewerage system. However, around the same period nearly every home in London had a cesspit beneath it together with the associated foul and deadly odours and it was not until the late 1800s that the connection between human wastes and disease finally began to be understood. Cholera epidemics during the period 1830-50 caused the deaths of tens of thousands of people and awakened the need for sanitation and reliable sewerage. In 1847 Parliament adopted a sanitary code that applied to England and Wales and 1866 heralded the last year of a cholera epidemic in London.

In order to protect the natural environment and public health UK civil engineers have, over a prolonged period, used their best endeavours to apply engineering judgement to capture and treat wastewaters generated from domestic sewage and industrial processes. As part of these efforts combined sewers were constructed to convey both raw domestic and industrial wastewaters plus surface water run-off flows generated during periods of rainfall. Cost-effective improvements in sanitary engineering have included the installation of storm sewage overflow chambers on each major sewer outfall to trap and capture the highly polluting ‘first flush’ of raw sewage flow that is released into pipes at the start of every storm. This flow tends to pick up much polluting matter that is deposited in sewers, which may include debris washed in from various outer parts of the drainage catchment, together with sediments that may settle out in older sewers that suffer from inadequate self-cleansing flow velocities. 

From the late 1950’s a standard stilling pond overflow design was employed on combined sewers throughout the UK to concentrate denser materials contained within sewage flows and to pass these forward for biological treatment. At the same time the lighter particle fraction of flow was retained behind an internal baffle wall until a rainstorm event had subsided, when this part of the flow was then passed forward to the treatment works. Thirty years later, under the auspices of the City Engineer, MEPAS was conceived and implemented under the jurisdiction of Liverpool City Council’s agency agreement with the then public water utility company North West Water. However in England and Wales, the treatment and supply of potable drinking water, together with the conveyance, treatment and disposal of wastewater, were transferred, through the sale of the publicly-owned and operated regional water authorities, to privately-owned companies in 1989.

Early in the 19th Century, most UK water and wastewater infrastructure was constructed, owned and operated by private companies but by the beginning of the 20th Century these responsibilities had been transferred to local government. Whilst in private ownership operating profits were all important, but the shift to public ownership was driven by the need to consider water as a public health necessity rather than a commodity. As a result, water usage was not metered and all associated costs were linked directly to property values. This system for water supply and water resource management continued until the 1970’s when regional water authorities were created based upon a single authority for each river basin or watershed retaining responsibility for all water activities, ranging from abstraction and supply, through to treatment and pollution prevention. At the time these arrangements led to considerable efficiency gains but these were subsequently hindered by a lack of government-backed funding. The resulting shortfall in infrastructure investment, coupled with substantial and chronic industrial pollution, gave rise to a continual decline in the quality of both raw and treated waters. In the 1980’s water sector investment was at one third of its level from a decade earlier and the stage was set for a return to water privatisation. And so the public-private-public merry-go-round had begun to turn yet again.

So what happened with the advent of the regional water authorities and the later creation of privatised water companies? In the Asset Management Plan 2 water authorities were charged with meeting a number of well-meaning standards. Not more than once per year discharges to high amenity watercourses were permitted of sewage containing particles measuring more than 6mm in two dimensions. For moderate amenity waters, similar restrictions were limited to no more than 30 discharges per year, and in the case of low amenity waters the provision of good engineering design incorporating stilling ponds or similar measures were required.

Even the large and hydraulically efficient stilling ponds incorporated into sewerage infrastructure during the late 1950s, that were further improved for MEPAS through the hydraulic testing of university laboratory scale models, could not guarantee that 6mm particulate matter contained within raw sewage would not be entrained within outfall flows. However, those individual stilling pond chambers specifically developed for MEPAS not only had enhanced particle separation performance but also had the distinct advantage of being of sufficient physical size and volume to contain the highly polluting first flush flow from each separate drainage catchment.

Unfortunately, UK water companies suddenly realised that by introducing 6mm mechanical screens into new smaller and more compact overflow structures, they could appear to comply with legislation at a much lower capital cost. Well-meaning legislation introduced during the 1990’s required that any particulate matter discharged from a storm sewage overflow should measure no more that 6mm in any two directions. To satisfy this requirement, water companies rushed to co-operate with mechanical screen manufacturers in the design and fabrication of screens with the required 6mm spacing. Collaboration also stretched to the production of perforated mechanical screen chambers. These initiatives lowered both fabrication and construction costs but increased operating costs due to the necessary inclusion of electrical power systems. At the time of their development however, the long term reliability of these screening devices could not be satisfactorily predicted due to the limitations of performance data derived from the available testing procedures adopted.

The cheaper and smaller overflow chambers now widely adopted throughout the water industry are, unlike the hydraulically modelled stilling chambers, totally dependent on electrical power. Hundreds of overflow chambers around the UK now rely on 6mm mechanical/electrical screen devices and are of insufficient capacity to capture the highly polluting first flush flow from each and every rainfall event. The first flush occurs at the start of a storm when all sorts of debris is swept from the drainage catchment into the sewers. In addition, all the solids that have previously settled in sewers with inadequate gradients for self-cleansing at low flows, also suddenly get swept forward at the front of the advancing storm flow. On hitting the new mechanical screens the overwhelming quantity of sewage debris knocks the mechanical screen out of action, and flows thereafter flow over the top of the screen and into the watercourse totally untreated. This remains the situation until there is a manned maintenance visit. The discharges at screened overflows may be recorded as a simple level exceeded device for reporting purposes, but unless the failure of the screen mechanics is similarly recorded and reported, this will be reported as a simple discharge event rather than a failed/untreated discharge. The problem now is that the water companies have elected to use an energy dependent device that appears to meet the required standards, yet invariably fails with the arrival of the first flush at the start of a storm.

Whilst previous designs were reliable, needing little maintenance, the new designs were totally electrical-energy dependent with inevitable repeated failures. Of course, the now rising costs of electrical energy will increase running costs which will be passed on to the customer. In reality, the well-designed chambers recommended for low amenity waters have a better overall performance that the 6mm mechanical screen chambers required for high amenity, so here is a great example of good intentions actually creating the opposite of the desired effect. Could this problem be addressed by making it a legal requirement to have a chamber adjacent to, or immediately upstream of any mechanical screen capable of containing the calculated first flush volume for the relevant catchment before the screen is engaged? It must be the case that these inadequate mechanically screened overflow chambers are now contributing to the high levels of pollution currently being reported in rivers throughout the UK. This all arises from well-intended legislation, followed by blinkered research and testing.

Back in Wonderland, the place is ruled by nonsense and so Alice’s normal behaviour becomes inconsistent. Following the publication of Lewis Carroll’s later work in 1872 ‘Through the Looking Glass’ the character of Humpty Dumpty appears on the scene. This egg-head’s role is a subtle reference to the 15th Century King Richard III, the humpbacked monarch who fell off a wall. Allegedly ‘Wall’ was the name of his horse and he became the last English King to die in combat during the Battle of Bosworth in 1485. In the early 17th Century Shakespeare perpetuated this tale by famously depicting the King as “a poisonous bunch-backed toad” and 400 years later his skeleton was uncovered beneath a car park in Leicester which permitted an updated diagnosis of severe scoliosis which causes the spine to twist and curve to one side. Disturbingly, uncovering a car park may become the norm if the numerous, cheaper, unreliable and energy intensive mechanical screen devices incorporated into smaller sewage overflow buried structures continue to contribute to ever-increasing river pollution. Humpty Dumpty choosing to correct Alice’s grammar and question the meaning of her words by saying “When I use a word, it means just what I choose it to mean, neither more nor less”, will no longer be a credible defence to the failings of the above: ‘well-intended legislation, followed by blinkered research and testing.’

In conclusion, the Cheshire Cat is unique amongst Wonderland characters in that it has an exclusive insight into the workings of Wonderland as a whole. Indeed, the creature is not threatened by any other character and is so able to maintain a cool, grinning demeanour. The animal’s calm explanation to Alice is that to be in Wonderland is to be “mad” and that Wonderland is ruled by nonsense. As a result, Alice’s normal behaviour becomes inconsistent with Wonderland’s operating principles. So perhaps UK privatised water companies’ collective behaviour has too become inconsistent with sustainable public health engineering practices and operating principles. Part two of this article may well offer further credible predictions.

Graham Olsen and Professor Robert Jackson

About the authors:

Graham Olsen is a Chartered Engineer, former senior manager within the UK utility industry and the former Assistant City Engineer of Liverpool. He is now an independent consultant and expert witness. E: graham.olsen@yourexpert.solutions

Professor Robert Jackson is the former Associate Head of the School of Computing, Science & Engineering at the University of Salford where he held the Mouchel-Parkman Chair in Sustainable Engineering Technologies in the Department of Aeronautical, Civil & Mechanical Engineering. M: 07976 361716; E: professorrobertjackson@gmail.com