Former Wisbech man Ryan Pettengell drowned at Bawsey Pits while trying to search for a missing teenager.
Best friend Wesley Moule (35) told the Citizen’s sister paper the Lynn News that he watched helplessly at the shore while Ryan (41), his best friend of four years, floundered in the lake.
Mr Pettengell was swimming out to the island in the lake to check if a missing 16-year-old boy was there when he got into trouble.
Mr Pettengell and the boy, who is from Ely and has not yet been officially identified, both died in the tragedy on Tuesday evening, which saw more than 70 people from the emergency services involved in the massive operation.
Mr Moule had been paddling with his three-year-old daughter Summer-Louise, who is also Mr Pettengell’s god-daughter, and said: “He was the best friend you could have. He was always there for you.”
The two men were part of a group including Mr Moule’s wife Christine and daughter, which had headed up to the lakes to make the most of the warm weather.
Shortly after their arrival at 5pm, Mr Moule said the group had been approached by a police community support officer searching for a missing teenage boy. A woman had swum to the island and thought someone was there.
Mr Moule said: “Ryan dived into the water to go and see if he could help. The girl who was with him said she could see the terror in his eyes.
“We could see splashing and his arms. He kept bobbing up and down. We could do nothing to get to him.”
Mr Moule was standing with two police officers when it happened but neither could help. He said his friend was wearing a wrist support because his arm was healing after a break.
But despite the tragedy, people were still swimming in the pits the day after the two deaths.
Assistant chief constable (ACC) Nick Dean said: “The tragic discoveries of both the teenager and the man came after an extensive search by the emergency services and volunteers.
“On behalf of everyone involved I would again like to offer my condolences and deepest sympathies to the families of those who have sadly lost their lives.
“This is a popular spot in this area for people to come and enjoy themselves, however, we would urge caution whenever swimming in unknown open waterways.”
Mr Pettengell, who lived in Lynn but had family in Wisbech, ran his own business, Norfolk Reuse and Recycle House Clearance Services. He had a passion for motorbikes and was restoring a Kawasaki GPZ000.