This would make a great ID student project.

We all know that our oceans are filled with plastic trash. The Vietnam-based Centre for Marinelife Conservation and Community Development is trying to capture floating waste before it gets there, by using some homegrown design and manufacturing skills.

The key problem with capturing waterway trash is cost. "Several tools to collect trash in waterways have been invented and manufactured around the world, but they either are at the experimental stage or are too expensive to replicate and address the needs of local communities," said Ms. Ho Thi Yen Thu, Permanent Deputy Director of MCD.

That's why they DIY'd it. "MCD and our partners have researched, designed, and built this river trash capture tool right here in Vietnam; and after one year of testing on the Song Hong we know that it works, collecting an average of 100 pounds of waste per day."

The materials used are industrial barrels for flotation, both square and round tube stock for the frames, welded wire fencing for the netting, and bamboo for the walkways.

Ocean Conservancy, which helped fund the project, says the device captures enough trash to require emptying every three days. "High-value plastic waste, such as bottles, will be sold to recycling facilities; while low-value plastics, like bags and films, will be sorted and processed by a [local] facility." And everything it captures will be catalogued: "Ocean Conservancy experts will work with Vietnamese scientists to analyze what is collected to better understand the sources of the waste and help create strategies to stop it at the source."

"Rivers often serve as a pathway for plastics to travel out to sea, so trash trappers like these are important cleanup tools," says Chever Voltmer, director of Plastics Initiatives at Ocean Conservancy. "What makes this particular model so unique and promising is that it is inexpensive, locally designed, and made from locally sourced materials."