A Pagham produce company held an 'environment week', with talks from people in conservation, setting up eco-initiatives and a river clean.
Barfoots of Botley cleaned the Pagham rife, which runs through their site, on Saturday.
Lucy White, a product development technologist for the company, said: "We arrived with low expectations regarding the weather but the West Sussex countryside was kind enough that we ended up cleaning the river in just our t-shirts at one point.
"We spent all morning cleaning up various sections both in and around the rife, collecting everything from drinks bottles to bags and an old shoe.
"Although everyone was rewarded with cups of hot chocolate and biscuits halfway through, we all agreed the most rewarding experience, aside from making a change to our environment was seeing how much the children enjoyed it."
The company's environment week also featured talks from the warden for the RSPB Pagham Harbour and Medmerry Nature Reserves.
Lucy said that a real 'take-away note' was when two three-year-olds turned to her and said 'These people are so naughty for dropping all this rubbish, we would never drop litter on the floor, why would you do it?'
She said: "If only we could all have the same attitudes as these three year olds, who see something as simple as picking up rubbish to be a natural part of life and are so dumbfounded as to why it is dropped in the first place.
"Perhaps we should start taking lessons from them."