Oil pollution in North Sea is ‘grossly underestimated’, suggests new report

Growing up in Aberdeen, Scotland, the shadow of the Piper Alpha disaster loomed large over our community. The tragic explosion of the oil rig platform in 1988 claimed the lives of 167 people. Back then, I was blissfully unaware of the ecological ramifications of that disaster. But the spill of 670 tonnes of oil wreaked havoc on marine life and had a lasting impact on the marine environment that I love to explore.

In recent decades, there has been a gradual decline in the number of oil spills and the volume of oil discharged from tankers, rigs, wells and offshore platforms. While incidents continue to occur globally – often in less scrutinised regions than the North Sea – the UK has, thankfully, not experienced another disaster of Piper Alpha’s magnitude since.

Does this mean that the UK’s oil and gas sector have cleaned up their act? They would certainly like you to think so. But ocean pollution isn’t just about large oil slicks that spread across the water’s surface.

As a new report, Sea Slick, from marine conservation charity Oceana explains, the extent of frequent, small-scale spills are still being grossly underestimated, even though big oil spills are less frequent.

The report reveals what it claims is the true scale and impact of chronic oil pollution in the UK, showing that for many years the North Sea has been subjected to hundreds of unaccounted for “chronic oiling events”. These are where oil is frequently released in lower volumes than those associated with large spills. This issue stems from a poorly regulated oil and gas sector and a lack of transparency in reporting, allowing oil and gas companies to mark their own homework.

Currently, a certain amount of oil pollution is permitted as part of routine operations for oil and gas developments. Companies can apply for oil discharge permits, which allow them to release a set volume or concentration of oil or chemicals into the ocean. This waste output is referred to as “produced water”. Produced water is a by-product of the oil and gas sector, which returns to the surface of the ocean as wastewater during oil and gas production. Produced water may be treated before release but still contains finely dispersed oil and toxic heavy metals, such as mercury and arsenic.

Oil and gas companies are regularly breaching their legal produced water permit allowances, Oceana’s report claims. Yet, in line with official government reporting requirements, these breaches are not registered as accidental oil spills. Indeed, Sea Slick counts a total of 723 permit breaching incidents in the last three-and-a-half years – that’s equivalent to 17 oil or chemical spills each month.

Currently these permit breaches aren’t counted as accidents. They’re not really counted as anything – other than permit breaches. If these unaccounted-for permit breaches are factored into official government data for accidental oil spills, Oceana estimates that the volume of oil spilling into UK seas increases by at least 43%.

The oil and gas sector are keen to reassure the public that chronic oil pollution can be quickly dispersed and poses a low risk to marine life or human health. Certainly, if incidents were rare, this might be a more persuasive argument. But they aren’t. Over time, the incremental release of toxic chemicals has a negative environmental effect. An estimated 248 spills from permit breaches took place within the UK’s network of marine protected areas between January 2021 and May 2024.

Why does this matter? Marine protected areas are regions of the ocean which have been given special designations to help preserve marine life and habitats. They have been created to protect rare, threatened and important habitats or species.

The release of produced water into areas, which have been singled out as especially important for protection, is shocking. Contaminants associated with chronic oiling have been shown to have a range of effects on marine life. The list is long: damaging cells and cell membranes, DNA damage (a common cause of cancer), the changing of gene expression and the disruption of reproductive functions. The steady leaching of toxic oil and chemical byproducts poses risks to human health too as toxic chemicals enter the food chain through farmed and wild-caught fish.

Getting serious about sanctions

Oceana’s research highlights that oil and gas companies have only been fined on two occasions in the last five years. One was for just £7,000.

The new government’s water (special measures) bill will force water companies to clean up the UK’s rivers and oceans. A failure to cooperate or any attempts to cover up data around sewage spills could see bosses jailed for up to two years. Water company bosses are finally being held to account. Will the UK government apply the same rules to the bosses of oil and gas companies who are also polluting our seas?

As the Sea Slick report notes, there is overwhelming public support for polluters to be held to account. By regulating and fining oil companies properly for chronically polluting UK seas, the government could enact and make permanent their commitment to end new oil and gas licenses. It’s time to take action.

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