[2] Waialua is a former (sugar) mill town and residential area, quite different in its quiet ambiance from nearby Haleʻiwa, which is more commercial and tourist oriented.

The Waialua Sugar Mill is the center of this town and the historical base of its plantation history.

The United States Postal Service operates the Waialua Post Office at 67-079 Nauahi Street.

HECO will buy electricity from this solar farm at 11 cents per kilowatt-hour (kWh) for 22 years.

[8] On September 10, 2019, the 49 megawatt Kawailoa Solar developed by Clearway Energy Group began its operation.

San Francisco-based Clearway's predecessor, NRG Energy's Community Solar division, took over the project at the end of November 2016.

[9] On January 22, 2019, the Clearway Energy Group obtained NRG Community Solar's assets.

[13] Many of the current families living in Waialua are the results of agricultural industry which began in the early 20th century.

Many of the families brought to Waialua during the sugar rush remained here and many of their descendants reside there today.

During World War II the twin guns from USS Saratoga were installed 1.5 miles (2.4 km) off Kamehameha Highway near Waialua for use as gun batteries attached to Hawaiian Pineapple Company Camp Brodie 4.