As clients start facing increasing water bills and shortages, questions about rainwater harvesting often start popping up.
But whether it’s for commercial or residential customers, designing a water harvesting system that is both effective and integrated into the irrigation takes more preparation than just putting a barrel in the backyard.
Kevin Rinschler, regional irrigation technical advisor for SiteOne Landscape Supply Inc., Roswell, Georgia, walked through those important starting steps in a recent project for the Nashville International Airport. He assisted Hawkins Partners Inc., Nashville, Tennessee, in the oversight and design work installing a water harvesting system in a parking garage while also meeting requirements for Parksmart certification, which measures high-performing, sustainable parking garages.
“We worked side-by-side with Hawkins Partners, looking at various options,” Rinschler says.
To start, when it comes to water harvesting, one of the first points to consider is why the client wants to install a system, he explains.
“One of the main things I look at is, what’s the motivation for your inquiry into water harvesting,” Rinschler says. The installation approach can be different if it’s to meet Environmental Protection Agency requirements as compared to just wanting to have a sustainable green lifestyle. It also helps qualify customers who are more likely to be able to complete the process.
That leads to a question about budget, which can be an eye-opener for some clients, he says. In both residential and commercial applications, customers often don’t know what the average price point is for a water harvesting system. For some smaller customers, that can be a stopping point, so Rinschler tries to cover the budget as early as possible.
Another question that he suggests bringing up quickly in the process is how much water is required. Home and building owners sometimes don’t realize the amount of water necessary to irrigate a landscape, he says.
“Once I get past the motivation, I start to look at justifying it in terms of overall square footage, using standard Irrigation Association calculations for estimating water requirements on a landscape,” he says.
He looks as the square footage of that estimate compared to the square footage that the harvesting system will cover to find the difference. If a customer has a large area to irrigate but only a small amount of roof area, there’s a significant imbalance.
It’s important to discuss that imbalance with the customer and outline what other water sources will make up that difference, he says. For the airport parking garage, the customer wanted a 20,000-gallon tank, which wouldn’t be able to cover all of its irrigation needs. But they had access to other water sources and were willing to pay those bills in supplement to harvested water.
Once those steps are out of the way, planning the installation becomes even more important, as irrigation contractors are often one of the last groups on the job site, Rinschler says. For the airport, a harvesting tank was placed underground and a galvanized tank was placed above ground, which meant that Rinschler and others had to be in constant contact with the other contractors.
He provided plenty of plans and directions to make certain that work around the tank was being done correctly and was looking at potential problems in the installation and ways they could be solved.
“It’s kind of like that golden rule of not painting yourself into a corner,” he says. “I always try to think ahead about what could go wrong, because I’ve got to help figure it out in a lot of cases. If I’m going to paint myself into a corner, I want to make sure there’s a window I can get out of.”
It meant site visits during the process and supplying detailed sketches of important access areas to contractors, he says. His attention to detail helped the job go smoothly, with the exception of a few small obstacles.
Water harvesting systems like the one Hawkins Partners installed at the Nashville International Airport can bring eco-friendly notoriety and water savings for customers. But just like any part of an effective irrigation system, doing it correctly takes plenty of planning.
The author is editor-in-chief of Irrigation & Green Industry and can be reached at firstname.lastname@example.org.