Thames Water released sewage into the River Lee and its tributaries more than a thousand times in 2023.
Environment Agency figures reveal wastewater from toilets, sinks and drains spilled out of storm overflows into the waterway 1,060 times and for an equivalent of 11,501 hours last year - almost double the 5,891 spillage hours in 2022.
Politicians say the scale of dumping in the river, a globally rare chalk stream, is “an outrage”.
A Thames Water spokesperson said untreated discharges are “unacceptable” and added the firm is “committed to stopping them from being necessary”.
Water companies use spillage from storm overflows when sewage treatment works cannot cope during heavy rain.
The Environment Agency recorded 3.6 million hours of spills across England in 2023, up from 1.75 million hours in 2022.
Signs for the Lee Valley White Water Centre and Cheshunt Community Hospital in Waltham Cross, Hertfordshire.
The River Lee
The River Lee flows through Essex, Bedfordshire and Hertfordshire before crossing into London near Enfield Lock and meeting the Thames south of the Queen Elizabeth Olympic Park at Stratford.
The longest combined discharge into the River Lee network was at Hatfield Heath in Essex, where sewage spilled into the Pincey Brook for a combined 2,289 hours – equal to 95.5 days.
At Cottered in Buntingford, Herts, sewage spilled into River Beane for 2,222 hours in 2023.
River Lee sewage discharge sites map. Credit: Environment Agency via Local Democracy Reporting Service, uses OS OpenData. Key: Brown - Discharge for more than one day; Orange - Discharge between 1-24 hours; Blue - Discharge less than one hour or none
'We have gone backwards'
“Clean water is a ‘basic of life’ and we haven’t even got that,” said Green Party councillor Vicky Burt, who represents Cottered at East Herts Council.
“It feels like we have gone backwards 150 years, when sewage was going straight into rivers.
“We need to either bring water back into public hands or up the fines for illegal releases so the water companies think twice about what they are doing.”
There were also major storm overflow discharges in 2023 at Brickendon, near Hertford, where Thames Water released sewage into the River Lee for a combined 1,390.75 hours.
An Upper Lea Valley Way sign towards Harpenden, Hertfordshire. Credit: Will Durrant/LDRS
The firm released sewage into the River Beane at Weston, near Stevenage, for 959.25 hours.
“It’s outrageous,” said Conservative councillor David Andrews, who is vice chair of the Lee Valley Regional Park Authority and represents Ware Rural on East Herts Council.
“A healthy river suggests the ecosystem is in a good state, so if we don’t have healthy rivers, we’re in trouble."
He added: “I believe in a free market, but even free markets have to have some controls.”
Some 85% of the world’s chalk streams – including the Upper Lee and its tributaries – are in England.
A Thames Water spokesperson said: “We regard any untreated discharges as unacceptable, and we’re committed to stopping them from being necessary, with the assistance of our regulators.
“Storm discharges are closely linked to rainfall and groundwater conditions and our region experienced above average rainfall for most of 2023, which saw an increase in the frequency and duration of storm discharges from our sites compared to 2022.
“We’re taking action to reduce discharges and have led the industry in this area with the building of the Thames Tideway Tunnel, a £4.5 billion investment, which is nearing completion and will remove 24 combined sewer overflows from the tidal Thames."
Discharges without wet weather, or “dry spills”, are banned because rainwater has not diluted the sewage and chemicals.
The Worst Discharges
- Pincey Brook at Hatfield Heath, Essex – 2289.75 hours
- River Beane at Cottered, near Buntingford, Hertfordshire – 2,222.25 hours
- River Lee at Brickendon, near Hertford, Hertfordshire – 1,390.75 hours
- Pincey Brook at Takeley, Essex, near Bishop’s Stortford – 1207.75 hours
- River Beane at Weston, near Stevenage, Hertfordshire – 959.25 hours
- Little Hallingbury Brook at Little Hallingbury, Essex, near Bishop’s Stortford – 846.75 hours
- River Quin at Barkway, near Royston, Hertfordshire – 627.25 hours
- River Stort at Stansted Mountfitchet, near Stansted Airport, Essex – 325.25 hours
- River Rib at Therfield, near Royston, Hertfordshire – 244.75 hours
- River Ching at Beech Hall, in Chingford, London – 187.75 hours
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here