An 11-year-old girl who drowned during a birthday party at a waterpark near Windsor, Berkshire, in August 2022 was unlawfully killed.
Staff at Liquid Leisure waited 37 minutes before calling 999 after a 17-year-old lifeguard spotted Kyra Hill struggling during a designated swimming area.
Senior coroner Heidi Connor concluded that Kyra had been unlawfully killed following gross health and safety breaches at the park.
The breaches relate to the depth and visibility of the water and the absence of an emergency plan and risk assessment, she found.
Kyra was seen in the water at around 3.20pm on 6 August 2022 with the lifeguard diving in to help her, before leaving the water to radio her colleagues.
While a manager attended rapidly, over half an hour passed before emergency services were contacted with the park owner first attempting to call a divemaster and an off-duty firefighter.
After missing several calls, Chris Knight answered the phone at around 4.19pm and first entered the water at 4.33pm, before discovering Kyra nearly 40 minutes later.
The diver said he searched two parts of the lake before he was told that CCTV showed her going under at another location.
He said that as far as he was aware no-one had looked at the CCTV by the time he arrived at the park.
Her father, Leonard Hill, fought back tears as he read a pen portrait of his daughter to Berkshire Coroner’s Court on Tuesday.
“Kyra was a beautiful, beaming beacon of light in the lives of all who were fortunate enough to know her”, he said.
He added: “With her naturally enchanting, bright, and beautiful eyes – paired with the softest, sweetest and warmest smile – she captivated hearts effortlessly.
“A spirited individual, Kyra was resolute in her beliefs. She would stand up for what was right without hesitation, always the first to challenge a bully or defend a friend.
“Guided by an unwavering moral compass, she was a protector at heart, fiercely caring for her loved ones and always considering the feelings of others.”
The coroner’s court heard that there were no signs warning of deep water despite it reaching 4.67 metres in parts of the designated swimming area.
“In fact the only sign present warned of shallow water”, she added.
Parents and carers were not advised to attend with children in a ratio of one to four, and young children were permitted to swim without buoyancy aids.
There was also no emergency plan or risk assessment that took those factors into account, and no control measures were identified and put in place to “take account of these clear risks”, she said.