The Walt Disney Co. will begin a major expansion project next month at its first Hawaii resort, a year after its opening.

Aulani, a Disney Resort & Spa will add a third pool, splash area for kids, two food stations and retail space to its Hawaiian-themed offerings on 21 beachfront acres in Ko Olina.

Construction will start Sept. 10 and be completed in mid-2013, the company said Wednesday in a news release. The cost of the project, which will coincide with the final build-out of the resort, wasn’t disclosed.

Along with the expansion, the resort is temporarily closing its Wailana pool and bar in October through the duration of the construction. Its Makai Preserve stingray pond will be permanently shut down for the new amenities.

The Waikolohe pool, two slides, a lazy river and Rainbow Reef snorkeling experience will remain open.

Aulani opened its first phase, including 217 hotel rooms, 73 time-share villas and the pool amenities last August. It launched its second phase consisting of 130 rooms and 134 villas in November.

Its third and final phase, including 274 villas, will open next summer.

The additional amenities were a result of customer demand, said Aulani spokesman Todd Apo.

"It’s never done," he said. "We will continue to listen to our guests and do what’s right to provide them with the best resort experience here at Aulani. A lot of it’s been listening to our guests over the last year. In their feedback to us they’re looking for more. We have found ways to provide our guests with more of what they’re asking for."

The new pool, splash zone and deck incorporating coral and lava will extend to the edge of the resort property, with an infinity edge adjoining the lagoon. It also will include a misty grotto that will feature an illuminated "starscape" on the ceiling and floor of the pool. In addition, the design of the kids’ splash zone will resemble tide pools and feature rainbow water jets, images of ocean creatures on the floors and hidden menehune in the cracks of the surrounding rocks.

A resort eatery adjacent to the new water play area and Wailana pool will offer continental breakfast, lunch and dinner options including sandwiches and salads, while a second beachside food station will serve grab-and-go snacks.

The expansion also will include a larger lawn area for weddings and other events and additional retail space for Aulani products, apparel and memorabilia.