During the early part of the 20th
century, the proportion of Hawaiians at Olowalu decreased as the number of plantation laborers from other countries increased. Hawaiians continued to raise kalo
, but only for their own use. Hawaiians also made money by leasing their lands to Olowalu Company.
The 1900 census does not clearly delineate Olowalu's population, making it impossible to obtain precise information. However, the census does confirm that Japanese and Portuguese workers had joined the Chinese and Europeans to form a more diverse community.
Although the majority of Japanese labor recruits continued to work for the plantation in this decade, there were a few exceptions. A couple named Kintaro and Kise Kawasaki purchased land and operated a truck farm in Olowalu. They also ran a store located behind the current Olowalu Store which was called the Olowalu Nihonjin Shokai
, or Olowalu Japanese Store.
By 1904, C. Sam Lung & Company, owned by H. A. Heen of Honolulu, operated a general store and coffee saloon managed for several years by C. Akuna and Hue Sung.
The 1910 census reports that 358 people lived in Olowalu compared to 231 in 1878. (Some employees of Olowalu Company lived in neighboring Ukumehame and are not included in this description of the Olowalu community.) By 1910 Koreans and Puerto Ricans had made Olowalu even more international. Approximately one quarter of the population spoke exclusively Hawaiian, Korean, Japanese, Spanish or Chinese.
The 358 residents of Olowalu in 1910 reported the following racial and ethnic backgrounds:
Puerto Ricans 75
By 1910 a Japanese Language School existed in Olowalu to teach Japanese children the language and culture of their homeland. Children attended the special school after regular Olowalu School hours. In 1910 a 19-year old immigrant named Kinhachi Tanaka operated the school.
C. Sam Lung & Co. store continued to sell groceries to the community over this decade. In 1910, the store continued to employ Hue Sung (also spelled Hew Shoung) as manager, plus a salesman, a servant and a cook, all of whom were Chinese. William Goo later took over the management.
The Church of Jesus Christ of Latter Days Saints maintained a presence in Olowalu in the 20th
century. A Mormon missionary resided in the community in 1910. Olowalu was one of eight branches of the West Maui Division of the church in 1921. The Olowalu branch consisted of both an adult group and a Sunday school class.
In 1916, 60 years after the first Catholic baptism, a permanent Roman Catholic church was built at Olowalu on the makai side of the road, a short distance from the Wailuku side of the mill. At that time, Father Bruno Bens of the Lahaina mission supervised the construction of the church dedicated to Saint Joseph.
By 1918 Pioneer Hotel Company under the management of George Freeland operated the Olowalu Theatre for the entertainment of local residents.
The 515 residents of Olowalu reported the following racial and ethnic backgrounds in the 1920 census:
Puerto Ricans 30
Olowalu's population had grown by 44 percent since 1910. Hawaiians still represented approximately 20 percent of the population. The Filipinos, an ethnic group not represented in the 1910 census, comprised 27 per cent of Olowalu's population by 1920.
Hawaiians reported employment on the plantation as skilled and unskilled labor, as government road workers, a police officer, a housekeeper for a private family and a chauffeur for a rent service. Two Hawaiians were truck gardeners. Some spoke only Hawaiian and four reported owning their land.
Nearly every non-Hawaiian worked for the plantation in either the mill or in the field. Those few who did not included three cooks, two housekeepers for private families, two independent truck gardeners, a yardman and two chauffeurs.
Six residents reported being involved with retail business in the census of 1920. William Goo managed the C. Sam Lung & Co. store, most likely with the assistance of two Chinese salesmen and a bookkeeper. The Olowalu Nihonjin Shokai, managed by K. Kawasaki continued to serve the Japanese community, probably with the assistance of a man named Takayama.
S. Hashibe taught the Japanese Language School that in 1922 enrolled 14 boys and 12 girls. In 1929, 24 Japanese residents and the Olowalu Nihonjin Shokai contributed $615 to construct a new building for the school.
In the 1920s, Olowalu Company treated the residents of Olowalu to a community Christmas tree and party during the holiday season. The Olowalu School children provided musical entertainment, Santa Claus brought candy and fruit, and then all sang songs and played games.