I directed Channel 4's Dirty Business and this is why we need to end the 35-year train-wreck of water privatisation

My eagle-eyed commissioners Alisa Pomeroy and Rita Daniels sent me their favourite tweet of the night after episode 2 of our new series Dirty Business went to air on Channel 4. A viewer, Josh Folks, had been checking Thames Water sewage dumps from a works in Islip.

“If I’d been s**tting into a river non-stop for 966 hours I’d probably have been arrested by now.”

Well, yeah. Fair point. You definitely wouldn’t be able to s**t into a river non-stop for 40 days without attracting the interest of the local constabulary.

But water companies get away with it.

Collectively they dump sewage into rivers and seas 1,600 times a day. The law says the water companies have to treat the sewage to make it safe, before they put it back into our waterways, except in very extreme, once in a blue moon, storm conditions. Every dump is an offence, punishable by five years in prison.

But the water police force – the Environment Agency – has never prosecuted any water company executive or owner or board member, ever. Not once. In the show, Chanel Cresswell’s Environment Agency whistleblower calls the agency a ‘Potemkin regulator’.

Potemkin was a Russian Field Marshall who had an affair with the Empress Katharine. He’s said to have built the facades of bogus villages to ride past and admire on her way to their booty calls. So Potemkin means something got up to look like something – in this case a regulator – which is in fact fake.

Factual producer Laura McCutcheon and I worked on Dirty Business for more than two years. Laura did the heavy lifting on the incredible amount of research. She met a person who worked inside the agency, called Dave Henderson. Coincidence? It was the same name as the head of the water company lobbying body who’s always on Radio 4 trying to defend their dumping. Duh… it was obviously a fake name.

‘Dave’ supplied us with internal Environment Agency documents and the results of his investigations into the Agency. They showed the Agency handing down policies which prevented its own investigators from doing their job properly.

’Operator self monitoring’ meant that the water companies were invited to self-regulate, ie report on their own crimes; and a policy trumpeted as moving the needle on climate change meant the investigators had their cars taken away from them… making it close to impossible for them to get to the rivers, coastlines and Sewage Works to investigate alleged sewage crimes.

Writing the script, it was vital to protect Dave’s identity. I made him a woman, and cast the incredible Chanel Cresswell to play him. But a year or more into our investigation, Dave’s circumstances at the agency had changed. They’d identified him as a whistleblower back in 2021 and after years of legal battles, he had eventually agreed to leave.

He’d given up a 21-year career to tell the truth about the Environment Agency. His real name is Robert Forrester, we name him in a card at the end of episode 3, and he is a national hero.

We met a lot of heroes. Heather Preen, who was 8, died after coming into contact with sewage marinated water in Dawlish, Devon in 1999. We met Heather’s mum, Julie, with the founder of Surfers Against Sewage, Chris Hines, in a garden centre tea shop outside Birmingham.

She’d had bad experiences with the media, but trusted Chris, who’d helped the family at the time of the Inquest, and Chris vouched for us. She decided she wanted us to tell her story. Julie and Laura spent the next year talking through every aspect of the Preens’ story, and providing the texture and truthfulness for the astonishing, heartbreaking performances of Posy Sterling and Tom McKay as Mark Preen, Heather’s dad, who eventually took his own life.

Laura spent months identifying and earning the trust of other victims and whistleblowers. Reuben Santer went surfing and got Meniere’s disease. Doctors don’t know the exact cause but he’s prone to vertigo attacks with severe vomiting; and could be battling this chronic disease for the rest of his life.

For the shoot, scores of real people (and their families) who’d contracted life-wrecking illnesses after coming into contact with sewage marinated water let rip on poor unfortunate actors playing (mostly) fictional water companies. The lovely actors were so traumatised by the pain and anger we all had a verbal group hug at the end of the shoot.

Then there were the proper national heroes. Ash Smith and Peter Hammond, the real-life investigators who’d uncovered the crimes of the water companies in an eight-year investigation. We met them early in our journey, and I decided to condense the whole massive story by making it their story.

And so Dirty Business became a thriller. The story of two real-life detectives (played with brilliance and humour by David Thewlis and Jason Watkins) who uncover the evidence and take it to the cops… only to find that the cops aren’t interested.

Dirty Business makes some serious allegations. Everything had to be underpinned by evidence. Laura pored over hundreds of pages of inquest documentation, trial transcripts, internal Environment Agency memos, log books from water company engineers, and Ash and Peter’s hundreds of emails with the water companies and the agency, and the granular details gleaned from these became the backbone of the storytelling.

This evidential basis formed the legal scaffolding of the series: the evidence was rigorously mapped to the narrative, so that every line in the scripts was underpinned with a corresponding evidential source. On set, Laura was nicknamed the ‘guardian of the truth’, there to ensure that whilst filming we remained faithful to the truth of what happened. She was constantly cramping my directorial style – but the actors loved it and thank god she’s so good at her job.

And then there was one last problem. Laura, Ash, Peter and many others had collected evidence of ecocide, horrific suffering, campaigners who couldn’t get a hearing in government, systematic law-breaking by the water companies and Environment Agency that was looking the other way – but the things the water companies were saying to justify themselves, and the policies the top brass at the agency were implementing… well, they were a farce. They were taking the Michael. It was funny.

In 2023 Laura and I had made Partygate, the true story of Boris Johnson’s 14 parties during the Covid lockdowns. For that film, I’d worked with brilliant comedy actors who were also amazing at drama (Charlotte Ritchie, Alice Lowe, Jon Culshaw, Kim Nixon). And for Dirty Business I thought ‘There’s some much suffering and tragedy in this series. But I just can’t play the water companies and Environment Agency straight: the situation’s too ridiculous.’

So for scenes inside the agency and South West Water I once again approached England’s funniest comedic actors - Alice Lowe (Prevenge), Charlotte Ritchie (Fresh Meat), Vicki Pepperdine (Getting On), Juliet Cowan (Pulling), Chanel Cresswell (This Is England), Ellie White (The Windsors) and Asim Chaudhry (People Just Do Nothing.) And in the end, 80 or so brilliant actors have us crying one minute, laughing out loud the next. Is that bad? Or just the way life is? Make up your own minds.

As to what the country needs now? Criminal prosecutions. Law-breaking water company execs, owners and board members banged up. Zack Polanski, leader of the Greens, now surging in the polls, is calling for a return to collective ownership of the water companies. Time to end the 35-year train-wreck of privatisation.

Dirty Business is available to watch now on Channel 4.

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