What’s in your rain barrel other than water? Off the Roof wants to find out

By acrall | February 22, 2018 3:47 pm

Many of us are familiar with the phrases “water is life” and “every drop counts,” but may still take our access to clean water for granted. Not until incidents like the lead poisoning of Flint residents or Cape Town running out of water do we become truly thankful for being able to turn on our taps and immediately drink the water that comes out of them. Incidents like those in Flint and Cape Town serve as constant reminders of how precious water is and that we should do what we can to conserve it – especially in our own homes.

That is why many homeowners have begun using rain barrels or cisterns to collect rainwater falling on their property, diminishing the demand for municipal drinking water supplies. Known as “roof runoff,” it is commonly used for such purposes as irrigation or filling our pets water bowls. But do we really know what are safe uses of this water, especially when it is coming off of our roof? The Urban Water Innovation Network (UWIN), a program funded by the National Science Foundation to assess urban water sustainability issues, wants to find out with your help.

Off the Roof is a new citizen science project developed to provide data to UWIN researchers to better understand what pathogens may reside in roof runoff collected in your rain barrel. “We’ve realized a real limitation in the use of roof runoff as an alternative water source in urban areas is the lack of data on the microbial quality of the water,” says Dr. Sybil Sharvelle, the project’s primary investigator, a civil engineer at Colorado State University. “This results in ambiguous regulatory guidelines for how the water needs to be treated for various end uses.”

The rain barrels that will be used in the Off the Roof project. Image credit: UWIN

Participants in Off the Roof will install rain barrels to their downspouts to collect water from precipitation events at three different times of year: winter, spring, and summer. As a pilot project, seven homeowners from four cities (Tucson, Baltimore, Miami, Fort Collins) were selected to participate.

“As a Maryland Master Naturalist and a SKYWARN volunteer severe weather spotter, you can say that I’ve always had an interest in citizen science, the natural world around me, and being a responsible steward of the environment,” said Amanda Leonard, one of the selected volunteers from Baltimore . “The ‘Off the Roof” project seemed like a great way to help my community while indulging my personal interests in storm water management, nature, and weather.”

With the help of volunteers like Amanda, UWIN hopes to gather feedback on how to best implement this project on a larger scale in the future, Sharvelle said.

“The approach developed through this pilot will allow us to collect runoff from a larger number of households in a larger number of cities.” That’s important because more data means more information to understand what may change the quality of water coming from your roof. The type of roof, the outside temperature, and wildlife use could all be predictors.

Buildings may also provide different results, so a teacher, Randy Walters, from the Polaris School in Fort Collins, Colorado will also be participating in the pilot, and is “excited to get my Chemistry students involved in doing some real research that will potentially benefit our world.”

UWIN researcher Jumana Alja’fari demonstrates how to take a water sample from the rain barrel in a training video. Photo credit: UWIN

He also remarked on the importance of this type of research for arid regions in the western parts of the United States. “I am curious about whether roof runoff can be a viable source of water for our population,” he said.  “With the Front Range growing by leaps and bounds, it will be crucial to develop as many varied water sources as possible.  Conservation methods and construction of dams/reservoirs will only be able to mitigate the demand/supply curves for so long.”

This exciting pilot project will be up and running in just a few weeks, and project participants will be using the CitSci.org platform for data storage and project communications. To stay updated on its progress, be sure to follow updates on their Facebook and Twitter account.

Want more citizen science? Check out SciStarter’s Project Finder! With 1100+ citizen science projects spanning every field of research, task and age group, there’s something for everyone!

  • OWilson

    The simple answer is “dirty water”.

    The ground water table is nature’s rain barrel, and it has the added benefit of filtering!

    The other question is whether we could incorporate a rain barrel into all modes of building and and individually treat the water.

    The natural efficient, and economic way to treat water for millions in cities, and even rural residential subdivisions is to cooperate and use centralized infrastructure!


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