"Even though the area looked clean, once we looked closely, we were staggered by how much rubbish we found. Cigarette butts were one of the biggest problems. They're everywhere," Thomas said.
Sustainable Coastlines' strategic partnership director Stephanie Vercoe said data collected by the charity showed unidentified hard plastic fragments were the most common pieces of rubbish found on New Zealand beaches, followed by glass/ceramic pieces, plastic food wrappers, cigarette butts and plastic bottle caps.
"Plastic is getting into our oceans and never goes away. It simply breaks down into smaller pieces, is eaten by fish and other marine life, and becomes part of our food chain."
She said beach clean-up days were a great opportunity for people to change their mindset and behaviour.
"Picking rubbish up really connects you with the issue. You suddenly think 'I might not use that single-use plastic bottle or those straws again. I'm not going to buy lollypops any more or have one of those little mints wrapped in plastic at the end of my restaurant meal'.
"It's those small steps towards sustainability that really make a difference. We always challenge people to come away from a coastline clean-up and pledge to no longer use a couple of the items they found that day. When you see the big pile of rubbish you've collected, it really drives the message home."
Vercoe said the more people talked about and noticed rubbish pollution, the more urgency people felt to do something about it.
"It's great when we have a corporate like TelferYoung who are starting those conversations and taking action on our behalf.
"They've given us a financial contribution which helps towards the running of our charity but they've really come on board with support as far as education, running events and community engagement which is hugely important to us."
Wednesday afternoon's clean-up will start at Kulim Park at 3pm and members of the public are welcome to join the TelferYoung team.
Rubbish sacks will be provided, and people should bring their own gloves and suitable footwear.
If raining, the clean-up will be postponed to Thursday, July 4.