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The District was formed in 1956 to develop a regional water system that provides a reliable water supply to customers in the greater Humboldt Bay area of Humboldt County. 

The District operates almost exclusively at the wholesale level. The District supplies drinking water to seven public agencies, who in turn, serve the residents, businesses and industries in our community. The District’s wholesale municipal customers are the cities of Arcata, Eureka, Blue Lake, and four Community Service Districts: Fieldbrook-Glendale, Humboldt, Manila, and McKinleyville.  For over 50 years, the District also supplied untreated water to two large industrial customers (pulp mills) on the Samoa Peninsula until the mills shut down.

Facilities include: 1) R.W. Matthews Dam which forms Ruth Lake in southern Trinity County,(Ruth Lake Community Services District) 2) a hydro-electric power house at Matthews Dam, 3) diversion, pumping and control facilities on the Mad River near Arcata, 4) storage and treatment facilities, and 5) two transmission systems that deliver treated drinking water or untreated surface water to customers throughout the Humboldt Bay region. 

The District is an independent special district governed by an elected five-member Board of Directors. The Board is experienced, capable and works well together. The District has had a long history of capable and committed Board members, with an average tenure since inception of 12 years.  

Diversion and Pumping Works

HBMWD installed five Ranney Collectors in or adjacent to the Mad River during the 1960s. The collectors draw water from the aquifer below the Mad River in perforated lateral pipes located approximately 60 to 90 feet beneath the bed of the river. The process of drawing water from the aquifer below the river bed provides a natural filtration process which results in water that is very high quality.

Currently, four Ranney collectors are operational. Today, they supply water to the HBMWD’s domestic system for drinking water purposes. In aggregate the Collectors are capable of producing approximately 20 to 21 MGD.

Hilfiker Pump Station No. 6 was constructed in 1976 to supply industrial water to the pulp mills. It is a direct diversion facility which is capable of pumping 60 MGD.