Kakaako is envisioned to become Oahu’s "third city" as it is redeveloped with thousands of homes, more retail, parks and upgraded roads and sewers. But no one, including the state agency regulating development in the area, plans to add any schools.

That’s a problem, according to the state Department of Education.

An estimated 50,000 people might live in Kakaako by 2030, up from 12,000 today. And of the five schools serving the area — two elementary schools, two middle schools and one high school — four are outside of Kakaako and all have historically drawn most of their enrollment from other neighborhoods.

Heidi Meeker, a DOE facilities development branch planner, got into a somewhat contentious discussion with Kakaako’s development agency, the Hawaii Community Development Authority, during a hearing on Wednesday.

The two elementary schools serving the area — Royal School and Queen Kaahumanu Elementary — are at capacity and can’t accommodate the population boom, Meeker said.

DOE initially notified the HCDA of its concern in November, according to Meeker, after plans were announced for two workforce housing towers producing more than 1,400 homes.

Since then, more condo tower plans have entered the development pipeline, having applied for or received permits from the HCDA.

Meeker said the DOE’s concern is elevated because the HCDA previously set aside state land next to Mother Waldron Park to accommodate a new school if necessary. But the site, which long ago was home to Pohukaina School, was recently committed by the HCDA for the 690 Pohukaina workforce housing rental tower with 804 units with no provision for school space.

"Very quickly we lost a school site," Meeker said.

The old Pohukaina School site, on Pohukaina Street between Cooke and Coral streets, is in the heart of Kakaako.

Of the five schools serving Kakaako, only McKinley High School is within the Kakaako area bounded by Ala Moana Boulevard and Punchbowl, Piikoi and King streets. Voyager Charter school is also in Kakaako, but is relocating and isn’t required to accept students who live in Kakaako.

Anthony Ching, the HCDA’s executive director, asked Meeker how much development would produce the need for a whole new school. Meeker said the plans by Kakaako’s two largest landowners, Howard Hughes Corp. and Kamehameha Schools, could be enough.

Hughes Corp. plans 22 towers with up to 4,300 units, and Kamehameha Schools plans seven towers with up to 2,750 units.

Meeker said the anticipated need would be for a new elementary school. McKinley and the two area middle schools have adequate capacity.

Ching said the HCDA will work with the DOE to address its concerns. But Meeker expressed some frustration that developers aren’t addressing impacts on schools from their projects.

The DOE has a mechanism by which developers need to address school impacts from new housing projects when farmland is urbanized at the state level or rezoned at the county level. Typically, developers provide land and increasingly are being required to put money toward school construction.

The HCDA has no similar requirement.

The DOE could designate Kakaako as an area where developers would be required to mitigate impacts on schools from their projects. Instead of being required to contribute a large parcel of land, typical for suburban schools, it’s possible a more compact urban school would be considered, Meeker suggested.

In the past, school impacts weren’t an issue for Kakaako, in part because enrollment in the schools serving the area generally has been on the decline since at least the mid-1990s, according to DOE data.

Of the roughly 4,000 students at the five schools serving Kakaako, only 450 to 500 live in Kakaako, according to DOE data.

There also was little impact on schools from Kakaako condo towers because much of what was built in the past 25 years or so comprised luxury units or units appealing to part-time residents with few if any children.

The current average family size in Kakaako is 1.8 people, Ching said.

But that is likely going to change with a new emphasis on developing more housing that’s affordable to local working families.

The HCDA sought developers to build workforce housing on the old Pohukaina School site, and tentatively selected a plan with 804 rental units proposed by Forest City Enterprises.

Local affordable housing developer Marshall Hung recently began construction on a 635-unit workforce housing tower at 801 South St. and also plans an adjacent sister tower with 400 units.

Also under construction in Kakaako is a 204-unit rental tower called Halekauwila Place reserved for low-income residents being developed by Stanford Carr on state land.

On Wednesday, Hughes Corp. won approval for a 424-unit tower it said would be mainly workforce housing affordable to people with moderate incomes.

Tower construction usually takes two years, which means initial expected impacts on the elementary schools from the present bunch of towers will begin relatively soon.

"The reason for our testimony is about our future," Meeker said. "We’re talking about 2015."