04 Sep 2023 5 min read

Human impact: the good, the bad and the inspiring

By Lewis Pugh

As Lewis Pugh reaches the halfway mark of his latest swim, he reflects on the damage humankind has inflicted on rivers and what can be done to repair the relationship.


It is humbling, experiencing a river so intimately. And there is really no better way to do that than to swim down it.

I started the Hudson swim two weeks ago at its source at Lake Tear of the Clouds, in pristine and beautiful wilderness. The water was a shallow stream at first, rushing over rocks as if in haste to get to the ocean 315 miles (507 km) away. I had to cover many miles on foot, following the twists and tumbles as the river grew in strength and volume through the Adirondack High Peaks wilderness. When it deepened enough for me to plunge in, the water was clear and cold. The feeling was delicious.

Black spruce, red spruce, balsam fir and tamarack rose like giants along the banks and reflected deep green on the water in front of me. I saw my first bald eagle perched at the very top of one of those trees, watching me as I swam by.

Hudson love

As we’ve followed the Hudson’s course and begun to engage with towns along the way, it has been heartening to share the love of this river with the people who live alongside it, and to hear them tell its stories. The Native American names – Adirondack being just one of them – echo the voices of the first people who lived here since the last ice age. I’ve visited historical societies and water treatment plants – 100,000 people in the Hudson valley drink from this river. I’ve talked to park rangers and conservationists, and I’ve been cheered on by families enjoying the last days of the summer holiday on the river’s banks. I’m grateful to every person who took time out to share their experience with me.

As the swim progressed I began to see evidence of the things people left behind. Abandoned mills and disused railway tracks told the story of industries that once thrived here. They shut down either because of economic pressures, or because of the damage they were doing to this vital catchment.

I have just reached the halfway mark, and while the people’s love for their river has certainly not diminished, the evidence of that damaging legacy is beginning to show.

Near Stillwater River Front Park, I encountered the first infestation of invasive aquatic plants. Water hyacinth and water chestnut (originally from South America and Asia) choke waterways and suffocate fish and other aquatic life. I also saw the first signpost instructing people to catch and release any fish they caught in the area due to high levels of PCBs (polychlorinated biphenyls) in the water.

PCB legacy

When the US Environmental Protection Agency (EPA) banned the production of PCBs in 1977, an estimated 1.3 million pounds (about 59,000 kg) of PCBs had already been discharged into the Hudson River from two General Electric* (GE) capacitor manufacturing plants.1

PCBs were released as a by-product of manufacturing electrical goods and lightbulbs and carpets – the things that made life pleasant and convenient for people in the short term. But in the long term, they are linked to cancer in humans and do untold harm to river ecosystems.

PCBs pose no immediate danger to me swimming through here, but their effect is systemic and devastating over time. PCBs settle in the silt on the river bottom, where they affect every organism, accumulating as they move up the food chain, which makes the fish unfit for human or animal consumption. PCBs have contaminated nearly 200 miles of the Hudson River, making it the country's largest ‘Superfund’ site.2 (Superfund is the name given to the environmental programme established to address abandoned hazardous waste sites. The law allows the EPA to clean up such sites and to compel responsible parties to perform clean-ups or reimburse the government for EPA-led clean-ups.)

It is a sad legacy for a river as mighty as the Hudson that it is both a Heritage River and a Superfund site.


PCBs are ‘forever chemicals’, and they sound a warning for rivers around the world. It is a warning to companies to count the environmental costs of what they do before they do it, because the consequences of their mistakes can be immeasurable – and eternal.

PCBs are invisible to the human eye. More and more plastic is too, as it breaks down into microparticles. Microplastic is becoming so widespread in our environment that one study estimated that we can take in the equivalent of a credit card’s worth of microplastic every week!3 The UN’s International Plastic Treaty, a globally binding agreement that will reduce plastic production and use through promoting a circular economy, cannot come too soon. 

With such overwhelming statistics, is there any point in encouraging people to get to know their local rivers and keep them clean and healthy, as I’ve been doing through our iheartrivers campaign? Yes, there is every point.

I understand that many of the threats to our rivers, which are by-products of industry or inefficient waste management systems, feel beyond the remit of ordinary people. But tangible proof of people power came in the first week of my swim, when a bill was passed stopping the decommissioned Indian Point Power station from releasing tons of radioactive waste into the Hudson. This came about because sustained of public pressure from grassroots organisations like Riverkeeper that got legislation over the line. Radioactive waste will never again be allowed to be released into the Hudson River.

For all the damage we humans do, our efforts to put things right can also be deeply inspiring.

On to the ocean

Now that I have reached the halfway point, I am acutely aware that every stroke I take brings me closer to the Atlantic Ocean. From Troy, the Hudson becomes a tidal estuary. I’ll be able to taste the brine as saltwater starts to mix with fresh.

I hope that is all I will taste, since the rest of my swim will pass by hundreds of CSOs4, or Combined Sewer Overflows. In simple terms this means that after heavy rains, human faeces, which would normally go to a treatment plant, join storm water drains and are swept straight into the river. Needless to say, I am praying for good weather.

The beginning of this swim was an inspiring reminder of how rivers should be: clean, clear and abundant. It was also a reminder that, while oceans have no choice but to welcome whatever rivers carry, we have every choice about what we put into them.

Rivers are life, and we are intimately entwined with them. Let’s treat them with the respect they deserve.

*For illustrative purposes only. Reference to a particular security is on a historic basis and does not mean that the security is currently held or will be held within an LGIM portfolio. The above information does not constitute a recommendation to buy or sell any security.


1. Source: https://www.riverkeeper.org/campaigns/stop-polluters/

2. Source: https://www.epa.gov/hudsonriverpcbs

3. https://www.independent.co.uk/news/science/microplastics-humans-inhale-credit-card-b2359982.html 

4. More than 27 billion gallons of raw sewage and polluted stormwater discharge out of 460 combined sewage overflows (‘CSOs’) into New York Harbor alone each year. https://www.riverkeeper.org/campaigns/stop-polluters/sewage-contamination/cso/ 

Lewis Pugh

Endurance swimmer and the UN Patron of the Oceans

Lewis Pugh swims in the most vulnerable ecosystems on Earth to call for their protection. He was the first person to complete a long-distance swim in every ocean of the world. He was also the first to swim across the North Pole and the first to swim the full length of the English Channel. Lewis has been instrumental in protecting over two million km² of vulnerable ocean – an area larger than Western Europe. At LGIM, we are united with Lewis in our aim to tackle the climate crisis. We believe inaction is not an option and are proud to support Lewis’ efforts to raise awareness and push for positive change.

Lewis Pugh