St. Luke’s Health System plans to build a $90 million hospital in Nampa and a $30 million medical plaza in Fruitland in the next few years.

The system this year borrowed about $150 million by selling bonds to pay for several projects, including the hospital and medical plaza.

David Pate, chief executive officer of St. Luke’s Health System, said the Nampa expansion plans are a response to increasing demand, not part of a growth plan.

“If you looked at our Meridian hospital, 20 percent of the patients that come there come from Nampa,” he told the Idaho Statesman. “Are we going to have to do a facility expansion at Meridian? That would be very, very expensive to do that. But frankly, we’re getting to some capacity pressures there.”

The new centers will follow the openings of medical plazas this year by the Saint Alphonsus Health System, which has a 152-bed hospital in Nampa that it acquired in 2010. Saint Alphonsus will open the doors of its new Fruitland health plaza in October and its new Nampa health plaza later this year.

St. Luke’s opened a $25 million medical plaza at Midland Boulevard and Cherry Lane in Nampa about two months ago, with a 24-hour emergency department, medical imaging and lab services and offices for primary care providers and specialists. That center has “been exceeding our expectations,” Pate said.

According to disclosures it made to bond buyers, St. Luke’s will expand that three-story medical plaza into a hospital with 80 to 100 beds, by building on land adjacent to the existing plaza.

St. Luke’s plans to break ground on the hospital in 2013 and finish it within 24 to 30 months, according to its bond documents.

The system also will build a two-story, 80,000-square-foot medical plaza in Fruitland. That complex will offer an emergency department, medical imaging, a lab and a walk-in clinic. It also will house primary care doctors and specialists.

St. Luke’s already owns clinics and provides cancer services in Fruitland. The health system will start building the full medical plaza next month and open it in May 2014, according to bond documents.

Audrey Dutton: 377-6448, Twitter: @IDS_Audrey