London’s Drinking Water

Hillingdon Green Party position paper – lack of protection of drinking water sources in Hillingdon December 2021

Water is important for human life and the economy. Good quality drinking water sources have served Hillingdon and surrounding areas, for many years. These are being built through by HS2 with serious environmental consequences.

HS2 is not a sustainable development if it depletes natural resources.

Hillingdon Green Party (HGP) condemns the lack of protection of sensitive public water supply wells during HS2 construction and running of HS2 through Hillingdon.

Damage is happening now December 2021

It is confirmed by Affinity Water Ltd that the main water source in South Harefield, Moorhall Road,is now closed due to increased water pollution during HS2 works. It is confirmed by HS2 Ltd that six inner source protection zones SPZ(1)s are being impacted by piling and tunnelling. HS2 have confirmed building additional water purification plants at Northmoor and West Hyde public water pumping stations. Water from the Colne Valley now goes through additional purification treatment before being supplied to customers.

HGP view on the above changes to the water supply system is that works are progressing which are having negative effects on raw water quality, intended for drinking water. This is illegal under the Water Environment Regulations (England and Wales) 2017 and not in the interests of the water drinking public. We have informed local MPs and the Local Authority but no action is being taken


Failures of controversial HS2 planning process

Alarm was first raised by Affinity Water Ltd (2013) in petition to parliament against HS2 which was damning of the proposed scheme. Page 7 para 23 reads;

‘Affinity Water Ltd and customers could be severely affected as the proposed works have the potential to reduce the quality and/or quantity of water abstracted to the extent that supply could be entirely jeopardised.'

In the HS2 Environmental Statement (2014) prepared for parliament, the impacts on the water supply system were not approved but moved forward in time, to be approved at detailed design stage. This means that the London Borough of Hillingdon (LBH) has a crucial role in determining lawfulness of the impacts of the Colne Valley Viaduct on the Drinking Water Protected Areas and groundwater.

London Borough of Hillingdon position statement on Colne Valley Viaduct can be found here:

Statement from Hillingdon Council on The Colne Valley Viaduct - Hillingdon Council

LBH asked HS2 for evidence of adequate protection of groundwater in the construction and running of the high speed rail development in Hillingdon. This was not provided. Delays ensued and LBH were taken to court and lost. LBH has very good grounds for appeal as negative impact evidence on the inner source protection zones is mounting.

However in March 2021 LBH dropped their appeal against the granting of planning permission for the Colne Valley Viaduct without sufficient information in order to make a lawful decision. The decision was taken out of their hands and decided in LBH’s absence, still without the information being disclosed.

The Colne Valley Viaduct in Hillingdon has never been through the planning process

HGP believes that Hillingdon Council is wrong to drop this judicial review against HS2. And this decision leaves the public water sources unprotected and at the mercy of unregulated development.

Sustainability of local fresh water sources is the long-term legacy that must be secured. There must be certainty that irreversible damage is not being done. UK law requires certainty at time of planning consent that no deterioration will occur at any public drinking water source.

Dubious use of sustainable planning development regulations

HS2 has jumped through hoops to make themselves appear legal. It is clear through HS2 paperwork they were aware of problems. In HS2 Phase One Environmental Statement (2014) (Volume 5 / Technical Appendices Route-wide appendix Water resources) the following information about the Mid Chilterns Chalk can be found from

The groundwater body that runs under the Colne Valley through Hillingdon is called the Mid Chilterns Chalk.

Page 67 ‘For the Mid Chilterns Chalk, a significant residual risk to the Drinking Water Protected Areas has been identified owing to the proximity of the Proposed Scheme to existing public water supply abstractions...............there remains the risk of Water Framework Directive deterioration with respect to the Drinking Water Protected Areas (DrWPAs) WFD element for chemical status.’

Page 97 Major Works 4.2.13 ‘Where it is assessed that such works could significantly affect such quality, flows or levels, discussions shall be held with the appropriate regulatory authority. Monitoring may be required to ensure there is no significant effect, and effective controls put in place if monitoring shows there to be the potential for a significant effect, whether temporary or permanent.

In the UK it is not legal to permanently pollute or damage public Drinking Water supply zones. Under European law any temporary effects on Drinking water supply sources would need a derogation under Article 4(7). This is a temporary exemption from strict environmental standards for a limited time.

There has been no derogation.

In 2019 Green MEP for London Jean Lambert enquired with the European Commission about UK applications for derogations in Drinking Water Protected Areas in Hillingdon.

Pollution of drinking water: the Mid-Chilterns Chalk groundwater body (Thames River Basin District, UK06) and the UK's obligations under EU drinking water legislation

The answers were very clear. The UK could not apply any more derogations from the WFD, DWD or Chemical directive as UK timescale for derogation to Drinking Water Directive had ended in 2012. The UK are lawfully meant to be conserving and improving Drinking Water chemical quality throughout the UK. Not making any of it worse even for a short time.

The Ickenham source (which is at the start of the Colne Valley Viaduct) is an example of a public drinking water source to which the UK have applied a derogation under Article 4(4) and 4(5) of the WFD, justified by disproportionate costs of the necessary measures. In 2012 the UK claimed that the financial cost of bringing the Ickenham water source up to good chemical status by 2015 would take disproportionate costs to achieve. The timescale was lengthened to be achieved by 2027. Hillingdon Council implemented a programme of monitoring the leachate around the landfill site which was identified as the cause of poor water quality at Ickenham pumping station. The people of Hillingdon would benefit from the improvement and bringing online again the 12.5 million daily litres of water licensed from Ickenham. This is not likely to happen with numerous HS2 impacts across the Ickenham source protection zone.

The answers to Jean’s questions can be found here:  Answer to Question No P-002104/19

The above answer clarifies that if UK Gov/HS2 had applied for a derogation for any Drinking Water Protected Area, this would have been turned down as out of time. No derogation was asked for and instead HS2 claimed that the works in the DrWPAs no longer needed a derogation. This was not backed up by evidence.

Throughout the period 2017 to 2021 HS2 withheld water risk assessments for their works in the Drinking Water Protected Areas. HS2 claimed they did not have to give the water risk assessments to the public as it was not in the Public Interest. This was challenged in court on 4 March 2021 by Hillingdon Green Party coordinator.

The Decision Notice by HH Judge Shanks upholds Green Party appeal and finds that HS2 illegally withheld the information which is of important public interest 144_190421_Green_S-EA2020-0088V_Judges_Final_DECISION-19_04_21

HH Judge Shanks Decision Notice ordered HS2 to release the Water Risk Assessments to the public.

Three HS2 water risk assessment were finally release (in full) on 21 May 2021. These can be found here. HS2 loses court case - Hillingdon

If this information had been available sooner,it would have been available to bring up in the civil injunction cases which HS2 repeatedly took out against protestors. This information could have made a material difference in the issuing of injunctions at the work sites. HS2 and the Crown Prosecution Service have relentlessly pursued peaceful protest at HS2 work sites in the Colne Valley. LBH has also taken out (at public expense) injunctions against Stop HS2 peaceful protest, on Harefield Moor and at (the now closed) Hillingdon Outdoor Activity Centre. Rise in injunctions against HS2 protesters

Following a demonstration at the Chiltern side of the aquifer on 14th September 2020, eight demonstrators were charged: “Watch or beset house or place to compel the abstention or doing of a lawful act”. The defence was that the acts of HS2 at that location were not lawful acts. As part of the defence an expert report “Hydrogeochemistry of the Mid Chiltern aquifer and its implications concerning the application of water quality regulations in the construction activities of HS2 was commissioned from Dr James D. R. Talbot PhD, MSc, BSc, ARCS, MRSC, CChem.

A few days prior to the delayed hearing Crown Prosecution Service/HS2 withdrew the case. The CPS letter to the defendants’solicitor states

The decision to discontinue these charges has been taken because there is not enough evidence to provide a realistic prospect of conviction.

The assumption is that they could not prove beyond reasonable doubt that the work on the Chiltern Aquifer was in fact lawful.

Court cases are ongoing, there is a court case scheduled for 21 February 2022 at Uxbridge Magistrates court against two protestors for scaling a pile driver at Harvil Road test pile site in February 2020. Hillingdon Green Party support these defendants.

Damage to water supplies affects more than one county

Hillingdon Green Party are not alone in calling for necessary action to safeguard public water resources from HS2.

On 5th May 2021 Chiltern Conservation Board and Buckinghamshire Council have similar concerns about the Chilterns bored tunnels up gradient in the Mid Chilterns Chalk.

Chilterns Conservation Board and Buckinghamshire Council Position Statement

On 5th June 2021 Chilterns Conservation Board Area of Outstanding Beauty and the River Chess Association share similar concerns.

HS2 and the Chilterns Chalk Streams - Chalk Streams | Chalk Streams

River Chess Association 24 June 2021

River Chess Association - Latest News

Wendover parish Council 6 May 2021

Concerns raised about impacts of HS2’s tunnelling operations

Fears for the future

There is still time for the Government to call a halt to works in the chalk aquifer before hundreds of deep piles are sunk across the DrWPAs for the pillars for the Colne Valley Viaduct. Piles of 25 meters deep have been drilled for the HS2 haul road across the lakes of the Colne Valley. At the time of writing, only one of the 56 really deep piles (up to 70 meters deep) has been constructed. HS2 must be required to demonstrate that groundwater sources can be protected, they must provide evidence to support this and make this evidence public before works with the potential to jeopardise public water supplies continue.

To achieve a sustainable society, sustainable drinking water supply systems must not be squandered. Nothing is more important than fresh drinking water