IT STARTED WITH a man named Hiram. In 1910, California governor Hiram Johnson signed legislation leading to the formation of municipal water districts throughout the state. Marin County, already in existence for 60 years, was quick to respond. In 1912, the Marin Municipal Water
District (MM WD), serving San Rafael, the Ross Valley and all of
southern Marin, became the first municipal water district in the
state. And one of MMWD’s first tasks was to build Alpine Dam,
which would provide drinking water for the county’s growing
population (two dams already existed locally: Lagunitas, built in 1872, and Phoenix Lake, built in
1905). Alpine Dam was designed in-house with consultation provided by M.M. O’Shaughnessy, the
well-known engineer of San Francisco’s Hetch Hetchy water system and at the time an MM WD
board member. According to the book Mount Tamalpais and the Marin Municipal Water District, by
current MM WD director and historian Jack Gibson, construction on Alpine started in the summer
of 1917, but the outbreak of World War I led to shortages of labor and materials for the contractor. So
in January of 1918 MM WD took over the building of Alpine Dam and it was completed a year later.
When first built, it held just over a billion gallons of water, but the dam was raised in 1924 and again
in 1941 — the structure now has a capacity approaching 3 billion gallons and continues to play a vital
role in supplying fresh water to thousands of MM WD customers. Curious water watchers can actually
drive over the scenic dam by taking the Fairfax-Bolinas Road southwest from the town of Fairfax.
Fair warning: it’s a long and twisty road and may call for a Dramamine or two. m
A first task of the Marin
Municipal Water District
was to build remote
Alpine Dam, which was
constructed a century ago.
BY JIM WOOD
In 1912, the Marin
became the first
district in the state.