A massive development on the Ewa Plain will help meet a demand for housing as Oahu’s population increases by 120,000 through the next two decades, its builder says.

Its opponents contend the master-planned Ho’opili will flood the residential market with excess supply because population will not grow as projected and the kind of housing proposed won’t be what buyers want and can afford, nor is it in a desired location. The development will also worsen traffic problems, putting tens of thousands of additional cars on the roads, even with a rail transit system up and running, they say.

Highway improvements that Ho’opili will pay the state to build will take the edge off traffic congestion, developer D.R. Horton argues. Moreover, its live-work community’s commercial elements will provide jobs close to home. But not enough to mitigate traffic, detractors say.

New housing will expand the city’s revenue base, Ho’opili’s supporters say. But the urban sprawl in tandem will require more city services, such as trash collection, police and fire units, street maintenance and sewage systems, Ho’opili’s opponents point out.

The 11,750 homes envisioned will tax water resources, dissenters say. Not so, says D.R. Horton and the city’s water experts. Of the 12 million gallons a day earmarked for Ho’opili, less than 4 million will be consumed, the Texas-based company estimates. Be that as it may, a state water official says, potable water on the island is finite and current models predicting availability are outdated.

So goes the testimony the state Land Use Commission has fielded since it decided last year to give the project another chance at making a case to reclassify 1,554 acres of agriculture land for urbanization.

Though the commission in 2009 rejected Ho’opili on a technical issue, it merely postponed a decision. In doing so, it has brought into keen focus the policy, rooted in Hawaii’s Constitution, that agriculture lands be protected.

For that reason, the commission must reject Ho’opili. If reclassification is approved, the constitutional mandate becomes meaningless, the bar for protection eroded.

The commission will have cover. The developer has shrewdly persuaded a number of key people and organizations to take its side.

The Abercrombie administration has endorsed Ho’opili, despite all its talk about food security and its flamboyant sustainability white paper. The loss of 1,554 acres, the state Department of Agriculture claims, is no big deal because there are thousands of acres for crops.

"Land is not the limiting factor to the growth of diversified agriculture," the developer’s consultant told the commission. But he and the department disregard the other elements necessary for such growth, including abundant, accessible water, irrigation infrastructure and market proximity, all of which makes the Ewa land prime for agriculture.

D.R. Horton has also recruited the Hawaii Farm Bureau Federation, which purportedly represents farmers, but at least one group has challenged the notion that the bureau’s backing reliably represents its members. Other farmers, including the widely respected MA’O Organic Farms, doesn’t favor urbanizing the Ewa acres.

The developer recently got an image boost by enlisting Ho Farms, another exemplary business, as the first tenant for the "urban farms" it plans to install among the houses. Ironically, Ho Farms is accepting the offer because it has not been able to find affordable land with long-term leases and water. If Ho’opili isn’t refused, the 18 acres Ho Farms will work may become an artifact, a sad model of what could have been a strong agriculture future.

Cynthia Oi can be reached at coi@staradvertiser.com.