In July 1921, the Division of Highways establishes its first materials testing laboratory in the unused boiler and coal rooms in the basement of the Temple of Justice in Olympia. The Testing Laboratory, directed by Materials Engineer Bailey Tremper, conducts physical tests on cement and aggregates used in highway construction. It is the forerunner of today's Department of Transportation Materials Laboratory.
Until 1921, testing for the state highway department was conducted by the City of Seattle Testing Laboratory. Supervisor of Highways James Allen wrote in his biennial report:
"While this arrangement was entirely satisfactory as far as the tests were concerned, it, by reason of its location, did not admit of the daily personal contact necessary on the part of the engineers responsible for carrying on the state highway work" (Ninth Biennial, 35).
The 1921 Washington State Legislature provided funds for the highway department to set up its own laboratory in Olympia. The department purchased a 200,000-pound capacity Reihle Bros. testing machine and acquired a 50,000-pound Olsen testing machine from surplus war materials. After these and some smaller equipment were set up in the basement of the Temple of Justice (home to the state Supreme Court), Materials Engineer Bailey Tremper and his two assistants commenced work in July 1921.
The state laboratory conducted physical tests on cement, sand, gravel, and crushed rock, and on paint and steel reinforcing bars. Since the laboratory was not equipped for chemical tests, those continued to be performed in Seattle. The physical testing allowed highway engineers to determine in advance what sand and gravel deposits would provide the best road materials, making more accurate construction cost estimates possible. It also determined which of many patented forms of concrete achieved the best results.
By the fall of 1923, it was apparent that the testing laboratory needed its own building. A one-story brick building was constructed at State and Adams in Olympia, and the laboratory moved there in February 1924. The new laboratory included the "necessary apparatus for chemical tests of materials of construction" (Tenth Biennial, 36), allowing the state to take over this responsibility from Seattle.