Members of the Coacoara Foundation, a local non-profitable foundation, cleared away about 25 bags of litter on the morning of Friday, April 2.
Items left by litter louts included: alcohol bottles (full and empty), t-shirts, an iPhone, two pairs of car keys, bottle tops, coffee cups, plastic bottles, a metal portable barbecue, cigarette butts, AirPods, metal straws and more.
Coacoara Foundation founder, Liam Ulla, who lives by Kite Beach, said: "I think this is the worst we've ever seen Sandbanks, and I've never seen Kite Beach treated this badly.
"I was there the night it all kicked off and it was mad - I have never seen anything like it in my life.
"Sandbanks has been ruined and we're trying to do something about it. We're working with the council to introduce more bins and signs. We also want to provide biodegradable and compostable bin bag dispensers so people can take their rubbish away.
"We are doing everything in our power to stop this."
The large quantity of litter was also spotted by fellow beach cleaner, Oly Rush, a plasterer from Upton.
He said "I spend most mornings going to Sandbanks to train for a big swim I’m doing, and I saw all the litter when I was driving past on Friday. When you see litter like that, it’s a big shock due to how bad it is.
"So many things need to change, but it’s difficult to change people’s behaviour especially as alcohol makes you lose your inhibitions. What got left behind on Friday was like what’s left after a big festival."
Ahead of the busy summer season that is expected for the conurbation, Oly wants BCP Council to introduce new measures to prevent large scale littering.
Oly said: "It’s inevitable that large groups of people will be travelling down here in the summer, so there needs to be beach patrols and wardens handing out bags for people to put their rubbish in. Wardens should use their powers and preventative measures, but in a friendly way.
"We protect what we love, and unless people learn to love the planet, they will never worry about taking care of it."
In response to the litter left on Kite Beach, a BCP Council, spokesperson, said: "We encourage everyone to treat our beaches with respect, dispose of their litter responsibly or take it home with them. "As part of our seasonal response plan for 2021, we have already recruited an additional 75 seafront staff to welcome people, keep the beaches clean and safe, and provide a greater security presence at key locations.
"Additional bins have been put in place along our seafront including Sandbanks and we urge people to #protectrespectenjoy."