The Kanagawa Waterworks Museum is a science museum located in Samukawa Town, Koza District, Kanagawa Prefecture. It introduces the history and development of Kanagawa Prefecture’s water supply system through exhibits and hands-on activities.
The museum was created by renovating the former water transmission pump station of Samukawa Water Purification Plant, which played an important role in establishing Japan’s first wide-area water supply system operated by a prefectural government. The historic building was also selected for the Ministry of Health and Welfare’s “One Hundred Selections of Modern Waterworks,” recognizing its historical significance.
The Kanagawa Waterworks Museum opened in 1984, commemorating the 50th anniversary of the establishment of the prefectural waterworks system. The aging transmission pump station at the former Samukawa First Water Purification Plant was renovated and given a new purpose as a science museum devoted to the theme of water.
In 2003, marking the 70th anniversary of the waterworks system, the museum underwent renovation and reopened in its present form.
Samukawa Water Purification Plant was established to respond to the rapid development of the Shonan region and the resulting increase in demand for water. Another important reason was the need to secure a reliable water supply and improve sanitary conditions for the Imperial Villa in Hayama.
In 1933, a plan to use underground water from the lower reaches of the Sagami River was approved by the Kanagawa Prefectural Assembly as the most economical proposal for constructing a water supply system. Construction of the purification plant then began in Samukawa Village.
The project was completed in 1936, making it possible to provide a stable water supply throughout the Shonan region.
In 1985, the former transmission pump station was selected for the Ministry of Health and Welfare’s “One Hundred Selections of Modern Waterworks.” Like the main building of the Kanagawa Prefectural Government Office, the structure has exterior walls finished with scratch tiles, preserving the distinctive architectural characteristics of government buildings from the early Showa period.
In 2013, the building was also recognized as a Civil Engineering Heritage Site Selected by the Japan Society of Civil Engineers. This designation once again highlighted its historical and architectural importance.
Inside the museum, visitors can enjoy a variety of hands-on exhibits that explain basic scientific principles in an accessible way. Among them are demonstrations of the Archimedes’ screw pump and the principle of the siphon.
These exhibits help visitors understand how water moves and how the principles of science are applied in everyday life. The museum also has a library containing a wide range of materials about water and the environment, making it a useful educational resource.
There is also a drinking-water corner where visitors can enjoy fresh water supplied directly from the neighboring Samukawa Water Purification Plant, allowing them to experience the results of the local waterworks system for themselves.
Outside the museum is an area known as the Water Plaza. A gently flowing stream runs through this space, creating a relaxing environment for visitors.
The stream has been designed to evoke the Sagami River. Trees representing the municipalities of Kanagawa Prefecture have been planted along both sides, introducing visitors to the region’s local greenery.
At the entrance to the plaza stands a fountain donated to commemorate the 50th anniversary of the establishment of the Kanagawa Prefectural Waterworks. Its splashing water serves as a welcoming symbol for the outdoor area.
The Kanagawa Waterworks Museum is generally open on weekdays other than Mondays, as well as on Saturdays, Sundays, and public holidays.
It is closed on Mondays, from December 29 through January 3, and during the five-day period from Monday through Friday in the fourth week of February. Visitors should take these scheduled closures into account when planning a visit.
The museum is open from 9:30 a.m. to 4:30 p.m. Admission is free, making it an accessible destination for visitors of all ages who wish to learn about water, science, and the history of public infrastructure.
The approach to Samukawa Shrine is one of the nearby attractions worth visiting. It has been selected as one of the “50 Beautiful Forests of Kanagawa,” and its attractive green surroundings make it a pleasant place for a walk.
Samukawa Water Purification Plant and Ichinomiya Park are also nearby. Together, these places offer opportunities to discover the area’s history, public infrastructure, and natural environment.
The museum can be reached on foot from either Miyayama Station or Samukawa Station on the JR Sagami Line.
For visitors arriving by car, the nearest expressway interchange is Samukawa-Kita IC on the Ken-O Expressway.
Visitors using local buses can get off at the Samukawa Post Office-mae bus stop, served by Kanagawa Chuo Kotsu and Sotetsu Bus routes.