William Henrichsen Neff was born September 22, 1905 in Salt Lake City, Utah the son of William Cyprus and Caroline Henrichsen Neff. During his teenage years, Neff worked at Frank Crocker's nursery. In 1925 Neff established the Mount Olympus Nursery which he operated until 1995 in addition to his landscaping work. In 1926 Neff enrolled at the University of Utah to study landscape architecture, but he majored in art and botany because the university did not offer landscape architecture courses at the time. Neff however took correspondence courses from the American Landscape School in Des Moines, Iowa, where he received his landscaping degree in February 1929. That same year Neff married Elizabeth Leggett and they later had two daughters, Caroline and Diana.

Beginning in 1930, Neff began working as a landscape architect. Although the market for landscape architectural work was small in Utah during the 1930s, Neff still managed to secure a number of residential jobs and received federal support for a few projects, such as his work at Fairmont Park in Salt Lake City. During the 1940s Neff received a contract to landscape the "booming" mining towns of Dragerton and Sunnydale, in Carbon County, Utah. During his work at these locations, Neff invented a turf planting machine (originally costing him $2,000), which improved his profits substantially. Neff was able to obtain several patents for his turf machine in the United States and also in several other countries, including Germany, England, Italy, Canada, and Sweden.

In 1952 Neff was asked to overhaul the Salt Lake Country Club's golf course. This project helped Neff establish a name for himself as a major golf course landscape architect. During this period Neff improved his knowledge of golf course architecture through personal study and also teamed with architect William P. Bell on a number of projects. During this period, Neff went on to supervise work on golf courses at Mountain Dell, Hobble Creek, and the Bonneville Country Club. After W.P. Bell died, Neff worked with his son, William F. Bell, on the Riverside Golf Course as a construction supervisor. Although Neff was primarily a golf course landscape architect, occasionally he also took residential and commercial jobs, as well as projects for the US National Parks Service. During the mid-1950s Neff oversaw the landscaping done at the Church of Jesus Christ of Latter-day Saints' Los Angeles Temple.

In 1967 landscape architect William Howard Neff (no relation) moved to Salt Lake and joined with Neff to design several golf courses. They worked on numerous projects in Utah, Idaho, Arizona, and other western states. Neff worked with William Howard Neff until 1981 when the latter started his own landscaping business. Neff continued on his own to design golf courses and country clubs until his death in 2001.

Over the course of Neff's career, he was also actively involved in local and civic affairs. Neff was the first president of the Holliday Lions Club, served as president of the Utah-Idaho Nurseryman's Association, was a member of the Sugarhouse Rotary Club, a member of the Surety Life Organization, and a member of the Red Butte Garden & Arboretum. Neff was also one of the early members of the American Society of Golf Course Architects and helped to write the organization's founding bylaws and constitution. Neff was also an avid golfer in his spare time.

Neff died at his home in Holliday, Utah on March 24, 2001. In 2002 William Henrichsen Neff was posthumously inducted into the Utah Golf Association Hall of Fame.