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Letter: Thames Water Has an Extensive Cleaning Programme

Published on: 26 Dec, 2020
Updated on: 25 Dec, 2020

From: Thames Water

In response to: Just Who Is At Fault When a Fatberg Forms In Your Sewer?

Thames Water has an extensive cleaning programme to ensure our sewers are free from blockages and flowing smoothly.

Last year, our proactive programme saw more than 900km of sewers inspected and cleaned, a 50 per cent increase on the previous year’s total and three times higher than in 2017/18. We plan to do even more this year.

We also removed more than 700 tonnes of materials from the sewers over the year, including wipes, fat and other debris which can cause blockages.

In the borough of Guildford, Thames Water has inspected or cleaned almost 10km of sewers this year, with more than another 5km still planned. In the last year, there were more than 850 blockages in the borough, with almost 200 of those caused by fats, oils and grease.

While Thames Water will always work hard to remove blockages in public sewers, those in internal pipes or sewers within a property boundary are the responsibility of the homeowner.

We encourage everyone to be careful of what they put down the sink and toilet to help avoid potentially damaging and expensive blockages in their own homes as well as our public sewers.”

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test 7 Responses to Letter: Thames Water Has an Extensive Cleaning Programme

  1. Jim Allen Reply

    December 26, 2020 at 8:43 am

    Simple question, when did this Section 94 cleaning programme start and why? Could it be because of the negligence discovered in August 2017 and a certain YouTube video?

    Certainly this programme was not in place before that date, nor for the preceding 40 years.

  2. Martin Elliott Reply

    December 26, 2020 at 10:54 am

    Unfortunately, neither author is offering a fully holistic analysis or solution(s) to this or general to several water utility company issues.

    Apart from the media coverage of “fatbergs” in large cities, I have no reason to doubt Jim Allen’s description of the time scale and cause of large fatbergs. However, asking people to only put three ‘P’s (paper, pee & poo) into domestic sewers is a cheap way to reduce the issue.

    As to treatment with preventative maintenance, Thames Water entirely ignores the root issue.

    They may spend a lot of resources/money on inspecting and cleaning sewers, and have increased it over recent years, but they have failed to show whether that is an adequate response.

    As with authorities, there is a major trend in failing to identify the scale of the issues. They may be spending a lot, but is a 10- or even 20-year programme to eliminate the issue an acceptable time scale.

    Another issue to illustrate this is the water leakage rate of the supply system. 16-20% of the potable water pumped into the system does not get to the taps; it’s lost to leaks. Whilst, apart from catastrophic failures, this chronic leakage isn’t too hazardous, somebody is paying for this wastage, probably customers in their tariffs.

    The water companies have a leakage reduction plan agreed with the regulator, OFWAT. Again they say this is a massive expenditure but is 30 years paying while reducing wastage an acceptable programme for customers.

    • Jim Allen Reply

      December 26, 2020 at 1:22 pm

      In respect of water leaks of potable water I can explain why there are so many leaks. It is down to water meters and poorly trained meter installers.

      With metal pipes you simply tighten and leave alone. The new plastic pipes “wind up” as the glands grip the pipe thus putting a radial strain on the pipe some distance away, up to half a metre from the join.

      If this stress is not relieved by undoing the joint, allowing the pipe to reset to its natural radial location, before a final tightening, some time in the future a radial fracture will cause a leak on the pipe.

      On my meter its was three years before the leak occurred and 18 months before discovery of the leak after some very high meter readings and some very wet foundations.

      If just one in 500 meters are installed with twisted pipes, it is little wonder water leaks are so high. Incidentally, we got a refund.

      • Martin Elliott Reply

        December 27, 2020 at 4:06 pm

        I’m afraid I can’t agree with Jim Allen’s extension of his experience to explain the whole non-network supply systems in various areas across the country.

        The systems leakage was well known decades ago, before domestic meters, when the industry was a nationalised operation. Like the sewage system, the potable water system is mainly over a century old with extension during housing developments. It’s why leaks before failure and catastrophic failures can be so catastrophic when a cast iron main crack reaches critical length, over-pressured or shocked.

        There is plenty of data on failure rates and modes, as there is for hazardous and non-hazardous cross country pipelines.

        When the industry was sold off one of the major negotiations concerned the aged infrastructure. Would new owners invest in bringing the pressurised water system and mainly gravity sewerage systems up to a reliable standard? The answer was said to be yes, but is the time scale reasonable.

  3. Anthony Mallard Reply

    December 26, 2020 at 6:25 pm

    I am sure Thames Water will be congratulating itself on its standard answer to any form of criticism.

    Sadly, as Mr Elliott illuminates, it is a partial answer that fails fully to address main issues in the questions posed. Questions that have more than once been put to them. Instead of dissembling, why don’t they take time to fully consider relevant points of concern and provide a straightforward and reasoned reply to the issues raised? Surely, that can’t be too much to ask.

  4. Dave Middleton Reply

    December 26, 2020 at 10:10 pm

    “Thames Water has inspected or cleaned almost 10km of sewers this year.”

    10km is about 6 miles.

    Bearing in mind there must be hundreds of miles of public sewers throughout the borough, six miles doesn’t seem to be much to shout about.

  5. S Peters Reply

    December 28, 2020 at 9:21 pm

    Perhaps Thames Water could now do something about the 13,000 hours they spent discharging raw sewage into our rivers last year?

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