The $155 million CityWay project under construction Downtown has a plan for raindrops, and it doesn't rely on street drains.

Rain that pelts the 10‐acre site will be stored in an underground cistern, diverted into two drywells, used to moisten a planted green roof or shunted into a 300‐foot‐long sunken garden. Nary a drop will go into city storm water drains, except in the worst of storms, said Rich Kelly, a civil engineer on the project.

CityWay, developed and being built by Buckingham Cos. of Indianapolis, taps the latest "green" technology that is fundamentally changing the design of commercial buildings ‐‐ even if it is mostly invisible to the public.

When it opens this fall, the hotel‐apartment‐retail complex at South and Delaware streets will be among the most energy‐efficient and environmentally friendly commercial developments in the city.

The water runoff plan, for one, stands out for the way it'll corral rainwater. It's the first time that Buckingham, a regional apartment and retail developer, has put a cistern on one of its properties. The 2,500‐gallon cistern will use stored rain to irrigate flowerbeds and other plantings.

Buckingham aims to achieve the third‐highest level of LEED certification for the project's 209‐room hotel, while also outfitting the apartments and retail space with a host of energy‐saving and environmentally friendly features. The Leadership in Energy and Environmental Design certifications, by the U. Green Building Council, rate buildings for achieving energy savings and low‐impact designs.

Almost all lights in CityWay will be low‐energy LED models, cutting power use 26 percent below standards of the state energy code. Heating and cooling systems, linked to sensors that turn off mechanicals when rooms are empty, will achieve the same reduction in energy use, while low‐flow faucets and other plumbing designs will cut water use by 20 percent in the Dolce‐brand boutique hotel.

Buckingham decided to ramp up the green features in CityWay for the cost savings they bring, as well as for marketing reasons and because it seems the right thing to do, said Scott Travis, senior development executive.

"To a degree, it's a differentiator" in marketing the 250 apartments to tenants, he said. "I think it's very important to some customers and maybe not so much for others." The apartments will be ready for move‐ins in October, with the hotel opening a month later.

Jeff Wylie, senior project manager at Circle Design Group in Indianapolis, which helped design HVAC and other systems in CityWay, said more developers are asking for more extreme green designs.

"It's becoming more and more common," he said, citing the Nature Conservancy headquarters and Eskenazi Hospital as notable new green buildings in Indianapolis. Kelly said the Indianapolis Cultural Trail's use of sunken rain gardens to control storm water showed him and other civil engineers that the concept can be applied to commercial building sites to good effect. "I learned a lot from that project," he said. "They work phenomenally well" in reducing runoff.

Then again, some green designs at CityWay weren't planned at all.

Buckingham's excavation of the site ‐‐ a former rail shipping yard for drug maker Eli Lilly and Co. ‐‐ turned up chunks of limestone used in old building foundations. It's piled on the site and will be used to build retaining walls and decorative landscaping.

Beats hauling the rock away and disposing of it as fill.