Mogden news updates

• 21 October 2009 Odour notification

  Owing to a system fault, one of the digesters (located in the south-west corner of the works) has overflowed and caused a spill.

• 19 October 2009 Sludge transfer main notification

  Yesterday (18 October 2009), a notification was sent out relating to a leak on Mogden’s sludge transfer main. The leak has been isolated, and we are using a different main to pump the sludge from Mogden Sewage Treatment works to the Iver South Sludge Handling Facility.

• 12 October 2009 Odour control unit fault detected

  A fault was detected on the odour control unit on the east side of Mogden at 8pm on Saturday 10 October.

• 9 October 2009 Odour notification

  We are experiencing some on-site odours in the southern part of the site.

• 8 October 2009 Minor sludge spill

  Late yesterday afternoon we had a sludge spill in the south west corner of the works, caused by digester number 11 that foamed around its seal.

• 2 October 2009 Planned maintenance work

  Our contractors will be diverting a water main on Monday 5 October 2009.

• 26 August 2009 Planned maintenance work

  Following our notification on 19 August 2009, we now plan to carry out our first odour control unit shutdown on Thursday 27 August 2009.

• 19 August 2009 Planned maintenance work

  We are carrying out some site improvements at Mogden that will help us to treat sewage more efficiently by converting some of our old primary tanks into final settlement tanks.

• 30 June 2009 Planned maintenance work

  Tomorrow afternoon (1 July) we plan to drain down one of the circular primary tanks on the west side of the works ahead of some essential maintenance work on the bridge system.

• 24 June 2009 Planned maintenance work

  We need to carry out some work on the pasteurisation plant.

• 9 June 2009 Planned maintenance work

  We need to carry out some essential maintenance work on the pasteurisation plant odour control unit.

• 3 April 2009 Planned maintenance work

  Next week we plan to carry out a routine service on the pasteurisation plant odour control unit.

• 6 February 2009 Planned maintenance work

  On Saturday 6 February we will be carrying out urgent maintenance works on the raw sludge transfer pumps and holding tanks, near the southern boundary, on the west side of Mogden Sewage Treatment Works.

• 12 January 2009 Minor sludge spill

  On Saturday 10 January 2008 we had a minor sludge spill at our pasteurisation plant located towards the south west corner of the works.

• 6 January 2009 Planned maintenance work

  On Thursday we plan to drain down one of the rectangular primary settlement tanks on the west side of the works.

• 9-Dec-2008 Primary settlement tank drainage

  Tomorrow, we will be draining down one of the westside rectangular primary settlement tanks to carry out some optimisation work on the scraper system.

• 29-Aug-08 Primary settlement tank drainage

  Next week we plan to carry out a study on one of the primary tank scraper system, located on the west side of the works, to see if we can make some improvements.

• 13-Aug-08 Planned maintenance work

  Tomorrow we plan to carry out some maintenance work on one of our rectangular primary settlement tanks, to the west side of the works.

• 30-Jul-08 Impending maintenance work

  Tomorrow we will be draining wash sump, near the pasteurisation unit on the west side of the works.

• 07-Jul-08 Digster work

  Tomorrow we plan to carry out some work on digester number 14 (south west corner of works).

• 27-Jun-08 - Primary settlement tank cleaning

  As part of the on going improvement work at Mogden we will be cleaning out the residual fat and grit from the East side circular primary settlement tanks commencing Monday 30 June for a period of eight weeks, we therefore plan to be completed by Friday 15 August.

• 18-Jun-08 - Primary settlement tank cleaning

  We would like to apologise for any increase in odour that may have been experienced as a result of the recent maintenance work on primary settlement tank number 14 (east side of the site).

• 06-Jun-08 - Primary settlement tank drainage

  On Monday 9 June 2008 we will be draining down primary settlement tank number nine on the west site of the works.

• 02-Jun-08 - Primary settlement tank drainage

  Tomorrow we will be draining down the rectangular primary settlement tank number 16 (located towards the northwest section of the site).

• 18-May-08 - Sewage sludge spillage

  Overnight we have had a sludge spillage from the pasteurised sludge holding tank, towards the south-west corner of the site. 

• 30-Apr-08 - Odour control unit maintenance work

  We have a specialist contractor coming onto site today to carry out some essential maintenance work on the odour control unit for the pasteurisation plant.

• 22-Apr-08 - Sludge spillage - update

  Yesterday, a notification was sent out regarding a spillage. This morning, the clean up was successfully completed.

• 21-Apr-08 - Sludge spillage

  We have had a sludge spillage in the digester area, towards the southwest corner of the site owing to plant failure.

• 17-Apr-08 - Digester cleaning

  Tomorrow we will be carrying out preparation work on digester number 14 in advance of cleaning work starting on the 21st of April 2008.

• 04-Apr-08 - Primary settlement tank work

  As part of the Odour Improvement Project, we will be carrying out some essential work on the eight circular primary settlement tanks towards the north boundary of the site.

• 26-Mar-08 - Primary settlement tank drainage

  We will be draining down and cleaning out Primary Settlement Tank Number 15 on the West side of Mogden sewage treatment works in order to carry out essential maintenance work.

• 25-Mar-08 - Plant trials

  We will be restarting the Pasteurisation Plant at Mogden STW on Tuesday 25th March 2008 to carry out further commissioning trials prior to fully restarting the plant in April.

• 18-Mar-08 - Impending digester cleaning

  Starting on Wednesday 19th March 08 we will be cleaning Digester number 7, near the southern boundary, on the West Side of Mogden sewage treatment works.

• 18-Mar-08 - Primary settlement tank drainage

  We will be draining down and cleaning out Primary Settlement Tank Number 11 on the West side of Mogden sewage treatment works in order to carry out essential maintenance work.

• 17-Mar-08 - Plant trials

  We will be restarting the Pasteurisation Plant at Mogden STW on Monday 17th March 2008 to carry out some commissioning trials prior to fully restarting the plant in April. The trials are expected to last until 4pm on Thursday 20th March.

• 05-Mar-08 - Minor sludge spillage

  We have had a minor sludge spillage in the south west part of Mogden Sewage Treatment Works.

• 21-Feb-08 - Impending vegetation removal

  As part of the East Works Improvements Project, our Contractor will be undertaking work to remove vegetation and a surface crust from the open channels that supply mixed liquor to the final settlement tanks, which are located towards the southern end of the site.

• 13-Feb-08 - Impending vegetation removal

  As part of the East Works Improvements Project, our Contractor will be undertaking work to remove vegetation and a surface crust from the open channels that supply mixed liquor to the final settlement tanks, which are located towards the southern end of the site.

• 06-Feb-08 - Impending vegetation removal

  As part of the East Works Improvements Project, our Contractor will be undertaking work to remove vegetation and a surface crust from the open channels that supply mixed liquor to the final settlement tanks, which are located towards the southern end of the site.

• 28-Jan-08 - Impending grit channel cleaning

  As part of the Odour Improvement Plan, we will be carrying out cleaning on Grit Channel Number 2, on the East Side of Mogden Sewage Treatment Works.

• 28-Jan-08 - Grit channel cleaning

  As part of the Odour Improvement Plan, we will be carrying out cleaning on Grit Channel, Number 2 on the East Side of Mogden Sewage Treatment Works.

• 21-Jan-08 - Primary settlement tank drainage

  We will be draining down and cleaning out Primary Settlement Tank Number 7 on the East side of Mogden sewage treatment works in order to carry out essential maintenance work.

• 10-Jan-08 - Primary settlement tank drainage

  We will be draining down and cleaning out Primary Settlement Tank Number 14 on the West side of Mogden sewage treatment works in order to carry out essential maintenance work.

• 04-Jan-07 - Primary settlement tank drainage

  We will be draining down and cleaning out Primary Settlement Tank Number 13 on the West side of Mogden sewage treatment works in order to carry out essential maintenance work.

• 24-Dec-07 - Primary settlement tank drainage

  We will be draining down Primary Settlement Tank Number 5, situated on the East side of the works, over the weekend to carry out essential maintenance work to a pump in this tank.

• 17-Dec-07 - Impending primary settlement tank work

  We will be carrying out some work on two of the Primary Settlement Tanks commencing on Monday the 17th of December 2007. 

• 17-Dec-07 - Impending sludge scraper installation

  As part of the Odour Improvements Project, our Contractor will shortly be installing a new sludge scraper in the bottom of Secondary Settlement Tank 1.

• 11-Dec-07 - Impending grit channel cleaning

  As part of the Odour Improvement Works, we will be carrying out further cleaning work on Grit Channel Number 1 on the East side of the works.

• 11-Dec-07 - Impending primary settlement tank work

  We will be draining down Primary Settlement Tank Number 2 on the East side of the works in order to change a pump in this tank.

• 03-Dec-07 - Impending work to settlement tanks

  We will be carrying out some work on two of the Primary Settlement Tanks commencing on Tuesday the 4th of December 2007.

• 26-Nov-07 - Impending Odour Control Unit shutdown

  The OCU will be shut down for a period of approximately 3 hours on Wednesday 28 November 2007.

• 19-Nov-07 : Impending cleaning work on settlement tank

  We will be carrying out some further cleaning work on the Primary Settlement Tank Number 4 on the East side of the works, on Monday 19th and Tuesday 20th November 2007.

• 14-Nov-07 - Impending grit channel cleaning

  As part of the Odour Improvement Plan, we will be carrying out cleaning on Grit Channel Number 1 on the East Side of Mogden Sewage Treatment Works.

• 14-Nov-2007 - Work required to Primary Settlement Tank Number 4

  We will be draining down Primary Settlement Tank Number 4 on the East side of the works to allow maintenance work to take place on the tank.

• 31-Oct-07 - Impending repair work on settlement tank

  We will be draining down Primary Settlement Tank Number 9 over the next couple of days to allow essential maintenance work to take place on the tank.

• 30-Oct-07 - Potential noise from site 1st-2nd November 2007

  As part of the Odour Improvement Project, our contractor is planning to remove some waste concrete from a concrete washout pit.

• 30 Oct-07 - Works to pipework due for decommissioning

  On Tuesday the 30th October 2007, we will be purging bio-gas from a section of pipework that is being decommissioned as part of a project that involves the removal of two redundant gas engines from the Powerhouse on the Southern end of the Mogden site. 

• 10-12 October 2007: Repair work to Primary Settlement Tank Number 4

  We will be draining down Primary Settlement Tank Number 4 on the east side of the site, to allow essential maintenance work to take place on the tank.

• 9th - 11th October 2007: Essential Work to Screens

  Essential work is required to be carried out on site on Screen Number 6 over the next few days. The work is due to commence during the morning of Tuesday the 9th of October until Thursday the 11th of October.

• 27th September 2007 - Odour Control Unit Shutdown

  The Odour Control Unit (OCU) on the East side of Mogden sewage treatment works will be shutdown for one day on Thursday 27th September 2007.

• 22 - 23rd September 2007 - Notification - Channel Cleaning

  Over the weekend 22 to 23 September 2007, residents may have noticed an increase in odour from the works. We believe that this is attributable to a channel cleaning activity that was undertaken to facilitate work on the odour improvements project.

• Wednesday 19th September 2007: Mogden Sewage Treatment Works

  We will be draining down and purging the Pasteurisation Plant on the West side of Mogden Sewage Treatment Works in order to carry out essential maintenance work.

• Monday 17 September 2007: Mogden Sewage Treatment Works

  During the early evening of Monday 17 September 2007, the Odour Control Unit (OCU) for Pasteurisation shut down on the West side of the site. Work is being carried out to resolve the issue with the Odour Control Unit.

• 10 - 14 September 2007: Draining & Cleaning of Primary Settlement Tank - Work Complete

  We have now completed the draining down and cleaning out of a Primary Settlement Tank (Number 8) on the East side of Mogden Sewage Treatment Works, this work was necessary in order to carry out essential maintenance work.

• 5-14 September 2007: Extension to essential work to Odour Control Unit - Work Complete

  We would like to confirm that the remedial work to the carbon units in the East Odour Control Unit (OCU), has now been completed.

• 5 -11 September 2007: Essential work to Odour Control Unit

  The remedial work to the carbon units in the East Odour Control Unit (OCU) has taken longer than anticipated and we will be continuing with this work for an additional week.

• 31 August 2007: Interruption in power to Mogden STW

  At around 2AM this morning (31 August 2007) there was a failure with the power, supplied by the local electrical company, to Mogden sewage treatment works.

• 29 August - 4 September 2007: Essential work to Odour Control Unit

  The Odour Control Unit (OCU) on the East side of Mogden sewage treatment works will be shutdown for one week from Wednesday 29th August 2007.  This shutdown is necessary to allow our contractor to continue with the remedial work to one of the carbon units on the OCU. 

• 16 - 20 July 2007: Draining and cleaning of Secondary Settlement Tank

  As part of the current investment to reduce odour at Mogden sewage treatment works it is necessary to continue the draining down and cleaning out of a Secondary Settlement Tank (tank number 4) on the East side of the Mogden.

• 17 July 07: Noisy work to be carried out near Northern boundary

  As part of the Odour Improvements Project at Mogden, our contractor needs to break out some existing buried concrete to enable the construction of a hardstanding area associated with the new (enclosed and odour-controlled) grit handling plant.

• 23 - 27 July 2007: Draining and cleaning of Secondary Settlement Tank 1

  On Monday 23 July 2007, we will start draining down and cleaning out SST number 1 on the East side of the Mogden site, in order to allow our contractors to carry out the work as part of the Odour Improvement Project.

• 12 - 13 July 2007: Noisy work near the Northern boundary on the West side of the site

  As part of the Odour Improvement Project at Mogden sewage treatment works, our contractor needs to remove a stockpile of surplus concrete from the site.  To facilitate its removal, our contractor will use a hydraulic breaker to break up the concrete into pieces for onward transportation to a recycling centre.

• 9-12 July 2007: Draining and cleaning of Secondary Settlement Tank

  As part of the current investment to reduce odour at Mogden sewage treatment works we will be draining down and cleaning out a Secondary Settlement Tank (tank number 4) on the East side of the Mogden site.

• 2-6 July 2007: Modifications near North Site Boundary

  As part of the odour improvements project at Mogden sewage treatment works, our contractor will be undertaking some noisy activities close to the embankment at the northern end of the site.

• 4-6 July 2007: Draining down of Primary Settlement Tank

  We will be draining down one of the Primary Settlement Tanks (PST) on the West side of Mogden sewage treatment works in order to carry out some essential maintenance work to the scraper in the PST.

• 5 July 2007: Essential work to Odour Control Unit

  Following the emergence of a fault on one of the carbon units on the new Odour Control Unit (OCU) on the East side of Mogden sewage treatment works, our contractor requires a shutdown of the OCU on Thursday 5th July 2007. This shut down is necessary in order to start the remedial work. 

• 18 - 22 June 2007: Grit channel cleaning work

  We will be continuing with the cleaning work to Grit Channel 2, near the inlet of Mogden sewage treatment works on Monday 18th June 2007. This cleaning work will take place during the day, between the hours of 9am and 5pm and will finish by Friday 22nd June 2007. Thames Water apologises for any increase in odour that may be experienced during this essential work.

• 12-15 June 2007: Commissioning work to Storm Tank 2

  As part of the current investment to reduce odour at Mogden, we have completed the work to Storm Tank 2 ahead of schedule, due to recent good weather, and we will be commissioning the storm tank starting today (Tuesday 12 June 2007).  This commissioning work requires the storm tank to be filled with some effluent in order to check the tank's control system, which may increase the level of odour from Mogden.

• 11-12 June 2007: Grit channel cleaning work

  As part of the current investment to reduce odour at Mogden sewage treatment works, we will be continuing with the cleaning work to Grit Channel 2, near the inlet of Mogden sewage treatment works, to the North of the site.

• 7 - 13th June 07: Emptying of Storm Water Storage Tank

  We will be emptying out the stormwater from one of the storm tanks (Storm Tank 1) on the East side of Mogden using mobile pumps, as the stormwater return pump is currently not working in Storm Tank 1.

• 22 - 25 May 2007: Cleaning work to grit flume

  Further to the notification sent out on 11 May 2007 Thames Water will be continuing with the cleaning work to grit flume number 2, near the inlet of Mogden sewage treatment works to the North of the site. The cleaning work will take place during the day, starting Tuesday 22 May 2007 and finishing by Friday 25 May 2007.

• Modification works near the northern boundary of Mogden

  Our contractor (Birse) will be continuing with the demolition work near the inlet works of Mogden sewage treatment works due to the presence of a large quantity of unforeseen mass concrete below ground level.

• 14 - 18 May 2007: Installation of the noise attenuator in the Odour Control Unit

  We will be installing the noise attenuator in the East Odour Control Unit (OCU) discharge stack at Mogden Sewage Treatment Works, starting on Monday 14 May 2007 and finishing on Friday 18 May 2007. This will require a shut down of the East OCU for 5 days.

• 14 - 18 May 2007: Cleaning out of grit flumes

  Further to the notification on 30 April 2007, Thames Water will be carrying out additional cleaning work to grit flume number 2, near the inlet of the sewage treatment works to the North of the site. This cleaning is necessary to allow our contractors to carry out the Odour Improvement Project work.

• 08 - 22 May 2007: Digester cleaning work

  Starting on Tuesday 8th May 07 we will be cleaning Digester number 16, near the southern boundary, on the West Side of Mogden sewage treatment works.  This cleaning work will involve pumping out the contents of the Digester and there may be an increase in odour while the work is carried out. 

• Saturday 28 April 07: Increase in odour on the West side of Mogden sewage treatment works

  During the afternoon of Saturday 28 April 07 one of the extractor fans had split its casing in the Thermal Oxidiser plant on the West side of Mogden sewage treatment works.  This caused a slight increase in odour for a short period of time.  The Thermal Oxidiser plant was stopped immediately to prevent a further increase in odour. 

• 01 - 03 May 2007: Cleaning out of grit flumes

  As part of the current investment to reduce odour at Mogden sewage treatment works, we will be cleaning out the grit from two of the grit flumes (flumes 1and 2) near the inlet works on the East side of the site. This work will allow our contractors to carry out the work of the Odour Improvement Project.

• Modification work to be carried out near the northern boundary of the site

  Our contractors (Birse) will be modifying the screenings sump near the inlet area of Mogden sewage treatment works. This work will involve breaking up the existing concrete road, which is likely to cause noise near the northern boundary of the site.

• 14 February 2007: Nighttime background noise survey

  Further to ongoing investigation work regarding the noise generated at the East Odour Control Unit (OCU) at Mogden sewage treatment works, our contractors (Birse) are planning to undertake a nighttime background noise survey. The survey will start in the evening of Wednesday 14 February 2007 and will finish the following morning (Thursday 15 February).

• Postponed: Nighttime background noise survey

  The nighttime background noise survey planned for tonight (Thursday 8th February) at Mogden sewage treatment works has been cancelled due to the severe weather conditions. The East Odour Control Unit will therefore not be shut down.

• 8 February 2007: Nighttime background noise survey

  Further to ongoing investigation work regarding noise generated at the East Odour Control Unit (OCU) at Mogden sewage treatment works, our contractors (Birse) are planning to undertake a nighttime background noise survey. The survey will start tomorrow night (Thursday 8th February) and will finish the following morning (Friday 9th February).

• 26 January 2007: Maintenance work to grit channel

  We will be cleaning out the grit channels (number 1) on the East Side of Mogden Sewage Treatment Works, adjacent to the screenhouse, to carry out some essential maintenance work. The cleaning work will take place during the day for one day only, starting tomorrow (Friday 26 January 07) and finishing by 4PM. There may be a slight increase in odour while the works is carried out.