A team of students from the University of California–Riverside (UC Riverside) Bourns College of Engineering recently received a $15,000 grant from the U.S. Environmental Protection Agency for a low-cost, environmentally friendly, reusable storm drain filter. The team received the funding as a phase one winner of EPA’s People, Prosperity and the Planet competition.

Storm-drain inserts can be used to filter out oil carried from runoff. However, existing filters have two primary issues: they are disposable and their lifetime is uncertain. The student’s filter, called Sustain-A-Drain, addresses both problems — it is reusable and has a replacement indicator.

Sustain-A-Drain is made from a blend of completely recycled polyester, rayon, and cotton fibers. Preliminary testing of the filter material shows that is can absorb six times its mass in oil with an adsorption capacity of between 73% and 87%. Students say the filter’s capabilities likely will increase with additional refinement.

The indicator is a three-dimensional printed device made from the same material as the filter and a translucent biodegradable plastic. The indicator includes a polymer that changes from a powder to a gel when it is saturated with oil and/or heavy metals and needs to be replaced.

Students tested the system in the living laboratory at UC Riverside’s Corporation Yard where 500 campus vehicles are maintained. The filter could address a need for industries and businesses that must implement control measures to prevent runoff contaminated with metals or oil from entering storm drains.

Students are now further testing the filter to determine how to best clean it, how many times it can be reused before being replaced, and how to treat wastewater resulting from cleaning the filter. Read more.