The legacy of the River Lea

Ancient times

Jim begins by taking us right back to the creation of the River Lea valley in the last Ice Age. About 10,000 years ago, the ice blanket came down to nearby Enfield. At the end of the Ice Age, melt water full of sand and gravel scooped out the shallow Lea Valley until it met what we now know as the Thames. The first recording of it being named the River Lea comes from Anglo-Saxon times in the 9th century when it marked the border between Saxon territories and those of the Vikings in what was then known as Danelaw. Legend says that blocking the river to cut off supply lines played a key part in the famous victory for King Alfred over the Vikings at Hertford.

1500s

Jim goes on to explain that in Elizabethan times, the River Lea was already an established trading route and breadbasket for London, bringing in grain for bread, malt for beer, and milk, meat and vegetables for markets. Human waste from London was taken the other way, as were bricks from one of Enfield's oldest established industries. At that time, the pastures and marshes of Tottenham were a valuable source of hay and other agricultural goods, which were also brought into the city via the Lea. To make this vital trade route smoother, various locks and cuts were brought in over the years to level, deepen and straighten the watercourse.

1789 onwards

As well as providing a trading route, the waters of the River Lea were used to power watermills along its banks. Two years before the Napoleonic Wars began, the crown created the Royal Gunpowder Mills at Waltham Abbey. The mill and River Lea supplied gunpowder to troops throughout the conflict, until the battle of Waterloo in 1815.

Around the same time, the Congreve Rocket Factory supplied the shells that rained down from British ships onto Baltimore's Fort McHenry, during the American War of Independence. The scene is immortalised in the lyrics of the American national anthem, the Star-Spangled Banner, which includes the verse; ‘And the rocket's red glare, the bombs bursting in air, gave proof through the night, that our flag was still there…'

These armaments suppliers, among others including the Royal Small Arms Factory at the Enfield, continued to use the River Lea to arm troops through the Crimean, Boer and both World Wars, helping to change the course of history.

Late 19th Century

This was a crucial period in the development of electricity. One of the early pioneers of electricity, Michael Faraday, had a workshop at Trinity Buoy Wharf where the River Lea meets the Thames. This is the site of London's first and only lighthouse, and Faraday's interest in maritime safety led to some of the earliest experiments in electric lighting for lighthouses.

Later, the river also had a role to play in the development of the electric light bulb, when Thomas Edison and Joseph Swan put aside their competing patent claims to form what became known as ‘Ediswan' incandescence lamp factory at Ponders End. From here, many other electrical engineers and entrepreneurs began to gravitate towards the Lea Valley, and it became a centre for some of the most important electrical innovations of the 20th century.

For instance, John Ambrose was working at Ponders End when he produced the world's first thermionic diode. This has been described by the IEEE as one of the most important developments in the history of electronics and directly led to the development of the wireless telegraph, radio, telephones and television. We might not even have computers, the internet or mobiles today without these early experiments happening in these quiet London backwaters.

Early 20th Century

Further down the river at Three mills near Bromley by Bow, Nicholson's had established a Gin Distillery, thanks to the import of grain down the river. It was here that a Jewish Russian immigrant by the name of Chaim Weizmann, made a vital contribution to the First World War effort. He came up with a method of turning grain into acetone which was crucial to the manufacture of cordite explosive propellants.

Having produced 30,000 tonnes of acetone to support the war effort, at Nicholson's and other factories around the country, Weizmann, who was a key Jewish activist at the time, was courted by well-known and respected figures such as Arthur Balfour, Lloyd George and Winston Churchill.

Although he constantly refused honours for his war work, he did make the case for a homeland for his people. By 1948, he had been sworn in as the first President of Israel. So it's not too far a stretch to say that the origins of the controversial State of Israel were first formed in Bromley by Bow.

Modern Day

The food industry continues to survive in the area, from all the way back from the 16th century when the Lea Valley was London's breadbasket. From the late 19th century, once open fields around Enfield, Edmonton and Tottenham began to be covered in glasshouses to supply Covent Garden with fresh salads, vegetables and fruits. This escalated after WWII, when a wave of Italian immigrants with expertise in glasshouse growing arrived. As this area of London developed, the glasshouse industry gradually moved further north up the Lea Valley, but it still thrives today across Hertfordshire and Essex, supplying a new breed of food processing companies in the Lower Lea. All the big supermarkets, food processors and new independents like Beavertown brewery have strong bases here, thanks to the road connections that grew out of the river route.

Meanwhile, the gravel pits that helped supply the concrete that rebuilt London after the blitz have now been converted to thriving nature reserves that give local people vital outdoor space. The creation of Queen Elizabeth Olympic Park in 2012 has helped to transform the quality of life by the waterside. Even the ‘Hammers' of West Ham have returned to site, not far from the Thames Ironworks and shipyards where the team was born.

What's fascinating about the River Lea is that it's constantly changing and evolving, but it always seems to have a foot firmly rooted in its industrial history. And what an amazing history that has turned out to be.