Brockham oil well lifespan extended

By Chris Caulfield, Local Democracy Reporter, 31 March 2025

An oil well on the edge of the Surrey Hills that has already produced almost half a million barrels will continue operating through to 2036 after being granted planning permission to pump waste water into the ground.

The Brockham Wellsite, in Betchworth, was given the go-ahead to truck in lorry loads of waste water everyday by Surrey County Council’s planning committee (S'ouvre dans une nouvelle fenêtre) on Wednesday, 26 March.

The oil field had been at risk of running low due to diminishing pressure inside the well  - but will now be able to continue pumping out oil until the end of its previously agreed  lifespan after councillors voted nine to one in its favour.

The application, by Angus Energy, was brought before Surrey County Council’s planning committee as the water being imported was a waste product derived from other oil sites.

Fresh water could not be used as it is important that any liquids pumped into the ground are broadly similar to what is already in the ground to avoid earthquakes caused by  swelling or clay erosion.

Officers told the meeting: “The application is required because the water being imported is waste product derived from elsewhere.

“The process would be conducted in three steps – HGV tankers bring in the waste water and it’s then stored before being injected into the oil well.”

Two tankers per day will be used to deliver water to the site during normal operating hours.

Any lorries making deliveries will be required to avoid  Brockham village.

The oil-well plans will cause no harm to the wider water environment or biodiversity officers said when recommending the proposals.

They said the overall benefit to the scheme outweighed any potential harm to the green belt and the waste water would maximise the efficiency of the oil well and  contribute to the UKs energy needs.

Objectors argued oil would be shipped overseas and contribute nothing to the country’s energy security.

Gerry Hamilton said: “Nothing more than being woken up with the earth tremors highlighted to me the importance of making sure proper due diligence is carried out.”

He said that the University College London had “published in-depth study indicating the Surrey swarm of earth tremors could be linked to changes in pressure in the sandstone.

“Seismic activity is an identified risk from water reinjection”.

Oil drilling first began at Brockham, between Reigate and Dorking in 1987 by BP and since that time about half a million barrels have been pumped out.

As a result in the huge volumes removed from the ground, pressure at the reservoir has dropped by about 500 pounds per square inch.

At this level there is only a very limited period of time that the well would be viable.  In the past pressure has been topped up through water being injected 

The plan is to inject water back into the well to return pressure to around 65 to 80 per cent of its original levels – and  in theory reduce tremor risks associated with oil drilling and water pumping.

Freshwater is not suitable as injected water should be broadly similar insanity to that already present in the reservoir in order to avoid swelling or causing clay to shift.