Rienow Hall: 21,370. English-Philosophy Building: 16,290. Macbride Hall: 15,355.

As of Wednesday afternoon, that’s the number of plastic water bottles saved at three locations on campus through a growing sustainability initiative at the University of Iowa.

The water filtration and bottle-filling fountains, called hydration stations, have been popping up around the UI campus since 2011, and officials say they’re looking to expand.

The high-tech stations combine filtered water with an electronic display that counts the estimated number of plastic disposable water bottles that have been saved by people using the fountain instead of buying individual bottles. In addition to three locations, thes stations are located in more than 15 buildings across campus.

Now, UI officials say the stations will be placed in any new construction or renovation project at the university, including the new art and music buildings and the renovation of the Main Library.

“The response has been very positive,” said Liz Christiansen, the director of the UI Office of Sustainability. “When you know the bottles are easy to refill, it reinforces the sustainable behavior.”

The project started in the fall of 2011, when the UI Student Government partnered with the Office of Sustainability and student organization Take Back the Tap to address plastic-bottle waste at the university.

Originally, one of the ideas involved banning the sale of disposable plastic water bottles at the university, but that came into conflict with the university’s contract with Coca-Cola.

Kelsey Zlevor, the UISG sustainability-initiatives director, said Take Back the Tap’s interests aligned with those of the student government.

“Take Back The Tap wanted to reduce people’s interest in buying disposable bottles,” she said. “It is fighting against the idea that plastic bottles are somehow cleaner or better, when tap water is just as safe and clean.”

Ashley Cheney, the president of Take Back the Tap, said while the organization still pushes for the elimination of plastic water bottles, the filling stations are a good first step.

“There are a lot more places for people to buy bottled water on campus than there are to fill up reusable water bottles,” she wrote in an email. “This is why Take Back the Tap promotes the installation of hydration station and gooseneck fillers, but why we are also devoted to eliminating bottled water all together.”

The compromise between the two came with the hydration stations and gooseneck filler spouts, which are attached to existing water fountains around campus, do not have the electronic counter and use tap water.

“The purpose of the hydration stations is to get people interested, and getting them to want to carry around reusable water bottles,” Zlevor said. “The goose-neck fillers aren’t as trendy, but once they’ve made the jump, the whole idea is to capture student attention and provide numerous places for them to fill up.”

Though the gooseneck fillers don’t have the same flashy look, they do have one clear advantage: the cost.“We’re paying about $1,200 for the hydration stations, plus installation,” said Bob Hradek, a senior facilities service specialist at the UI Facilities Management. “But the filler spout we buy for $100, plus $250 to $300 for installation. We put a lot of those in; it’s a pretty economical way to get filler stations.”

In addition, existing water fountains can be retrofitted with the gooseneck fillers, unlike the hydration stations, which require a complete reinstallation.

However, if the fountains themselves need to be replaced, Hradek says they will usually put in hydration stations.

“Drinking fountains fail from time to time, and we replace them [with hydration stations] in high-traffic areas,” he said. And the word is getting out.

“We can see by the counters that they’re getting pretty heavy use. As people see them, we get requests,” Hradek said. “We’ve gotten some from the English-Philosophy Building, the College of Public Health, and Phillips Hall.”

The first hydration station was installed at the IMU in the spring of 2012, and since then, the movement has expanded across campus, with stations in more than 15 buildings across campus and more coming.

“Seeing it spread in less than a year has really been awesome,” Zlevor said. “What’s telling will be the next few years, looking at the waste and how much of that is still plastic. Hopefully, there’ll be an indication that it’s going down.”