Professor Purrkis Ponders Purple Pipes: A Story about Recycled Water is designed to teach students about the treatment process involved in cleaning wastewater so that it can be reused for irrigation and agriculture. The story begins with Otis Turtle, Claire Bear, and Presley Peacock, three friends who decide to work together on a class project about recycled water that their teacher, Mr. Hoo, assigned. In order to find out more information, the friends seek out the help of their neighbor, Professor Purrkis. Otis, Claire, and Presley learn about the process wastewater goes through, flowing from their homes through each step at the treatment facility and finally to the wetlands where the water is treated naturally prior to being used. They even learned that the purple pipes and sprinklers they see in their neighborhood mean that the area is using recycled water. With the information from Professor Purrkis, Otis, Claire, and Presley complete their school project and they know exactly who to ask about similar projects in the future.