Newbuild homes and sewage

In response to The Daily Mail’s recent article, the ECP would like to inform you of the situation with sewage infrastructure in Moreton-in-Marsh and its implications on newbuild homes for the Cotswold District.

The ECP received a legal opinion from a specialist planning barrister at Landmark Chambers supported by renowned solicitors, Leigh Day.

In summary:

• Where there is evidence of inadequate capacity or clear legal non-compliance at a Sewage Treatment Works (STWs), it is lawful for Local Planning Authorities (LPAs) and planning inspectors to use Grampian conditions to prevent the commencement or occupation of new houses.
• It is also lawful for a Grampian condition to be applied until work to upgrade the local sewage works is complete to deal with future and current needs.

The infrastructure of Moreton-in-Marsh sewage treatment works (STW) has not kept pace with development due to a significant lack of investment in the town from Thames Water. Simply this means that the STW and associated infrastructure does not presently have sufficient capacity to cope with the existing number of houses connected to it and by extension the thousands of new builds expected to be connected to it over coming years.

In essence, Moreton-in-Marsh STW and the upstream Primrose Court Sewage Pumping Station are non-compliant with their Environment Agency permits and are currently being investigated by the Environment Agency as part of a wide-ranging criminal enquiry.

Evidence of overcapacity at Moreton-in-Marsh STW

• Citizen science samples taken from Moreton-in-Marsh shows very high levels of phosphorous entering the river below the STW which is of significant environmental risk.
  
  Local citizen scientist and advocate Sam Frith says: “The environmental impact Thames Water is having on the River Evenlode and the results they are finding are very concerning, which starts in Moreton-in-Marsh. Of the 66 samples taken below the Moreton sewage treatment works, 0% have come back as being ‘good’ water quality in terms of phosphorous, nitrogen and turbidity”.

• The Urban Wastewater Treatment Directive of 1994 requires water companies to prevent untreated sewage being released (subject to site specific use of best techniques, not involving excessive cost) unless there is weather of exceptional circumstances.
  
  Over the last 6 months untreated sewage from 3 outfalls owned by Thames Water in Moreton-in-Marsh has spilled for over 560 hours, with a lot of this during dry weather due to groundwater ingress which is not permitted (I.E. ILLEGAL).
  
  Thames Water themselves acknowledge this illegality from groundwater ingress in their Groundwater Impacted System Management Plan (GISMP) by saying: “Within recent years there have been unplanned UNCONSENTED unavoidable discharges in the network as a result of surcharging manholes causing pollution incidents”.

• Population equivalent has surpassed the Moreton-in-Marsh STW capacity: “The STW (Moreton-in-Marsh) is operating at a declared Population Equivalent (PE) capacity of 5,708 and is currently serving a PE of 6,346 and due to rise to 7,008 by 2030 (end of AMP8). Pretty convincing argument for an upgrade to a design capacity of 7,500 to give some headroom”. (Geoff Tombs, Windrush Against Sewage Pollution, 2024).

Conclusion

Thames Water were expected to upgrade Moreton-in-Marsh STW by March 2025 during their Asset Management Plan (AMP) 7 period, but then reneged on this and delayed into their future AMP 8 periods with a 2027 completion date ‘planned’ (we have little hope or expectation of this date being achieved).

There is also currently no target to address unpermitted spilling of untreated sewage from Primrose Court Sewage Pumping Station, other than the entirely unacceptable target date of 2040-45 to meet ‘all government targets for storm overflows’.

This evidence provided here clearly shows the capacity issue Moreton-in-Marsh STW has, and why it is logical and reasonable for planning authorities to intervene on new development in the area, until the sewage treatment works is upgraded adequately.

Ann Berkeley, ECP Project Manager, comments that: “There is little hope for improvement in water quality in the River Evenlode if upgrades and infrastructure improvements are not given high priority, we no longer trust in promises from Thames Water, we need to see action NOW”.

Sam Frith, local citizen scientist and advocate, says: “Afterall, Cllr Joe Harris, Leader of Cotswold District Council, has stated time and time again that they are ‘committed to an infrastructure first approach to development. What’s more, upgrading infrastructure in Moreton, such as its wastewater treatment works, are high priority issues that we will try to resolve in the Local Plan Update.’ Let’s see if Cotswold District Council really mean it”.

ECP is NOT anti-development. Rather, we are simply pro-clean rivers. Without adequate controls on new development linked to suitable upgrades of sewage infrastructure by Thames Water, the future for the aquatic environment, and thus public health, is bleak. Professor Chris Whitty raised just this concern recently in a paper released by the Royal Academy of Engineering.