Halawa (Hawaiian pronunciation: [həˈlɐvə]) is a census-designated place (CDP) in the ‘Ewa District of Honolulu County, Hawaii, United States.

Today, the water of Pearl Harbor has been highly contaminated by nuclear defueling and other toxic influences, and has thereby been designated as a Superfund site.

Although many sites were destroyed by the invasion of Kahekili II and especially by the building of the highly controversial H-3 Freeway, many remain and are cared for by Kanaka Maoli Aloha ʻAina practitioners to this day.

At least two species were driven to probable extinction (none have been sighted since construction began), many more are declining rapidly, the main aquifer of the area was badly damaged, and religious sites were seriously impacted.

In 1993, thirteen cultural practitioners were arrested while conducting a ceremony to pray for the healing of the valley.

Today, some of these caretakers, many of them kupuna (elders), have returned to care for the sites, although they now do so through a layer of soot and with the roar of the freeway as a constant sonic backdrop.

The Hale O Papa and luakini are mentioned in the massive collection of Bishop Museum reports that took many years to finally be released.

On the east side of H-3 are found the State Animal Quarantine Station and the Halawa High and Medium Security Facility (main O‘ahu prison).

The interfluve (uplands between valleys) on the west comprises Halawa Heights, extending up to Camp H. M. Smith.

[7] According to the United States Census Bureau, the CDP has a total area of 2.3 square miles (6.0 km2), all land.

The route of H-3 extends from its western terminus with east–west Moanalua Freeway (H-201; connecting eastward to Honolulu or westward to H-1 and Aiea) to the 1100-foot (335-m) elevation entrance into the Tetsuo Harano Tunnels, penetrating the Ko‘olau crest.

A significant proportion of H-3 within the valley is carried on the Windward Viaducts; although very expensive to construct, the viaduct is the only way to construct a freeway of this magnitude through such a narrow valley without flooding and destabilization concerns; it is also believed to offer some returns in terms of preservation of both archeological sites and stream ecology.