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How deep will I have to drill for water?

It depends on the geology you are in:

  • Franciscan Formation: usually
    between 150′ to 300′
  • Sonoma Volcanics: 200′ to 800′
  • Wilson Grove Formation: 120′ to 400′
  • Glen Ellen Formation: 200′ to 500′
  • Petaluma Formation: 150′ to 400′
  • Alluvium Formations: 40′ to 250′
  • Great Valley Formations: 150′ to 300′
  • Continental Formation: 100′ to 300′

How do you know where the water is?

Drilling a successful well depends on the geology of the site. Many geological conditions make finding water routine. The coastal and inland Franciscan and Great Valley formation are successful when we penetrate the right rock. It is important to have a good understanding of local geology.

Do I need to obtain a permit?

Within Sonoma, Mendocino, Marin and Lake counties, a permit is required. The costs vary in every county. Fisch Brothers will process the permit if given the necessary basic information from the customer. It can take approximately 1-2 weeks to be approved.

How much water is necessary?

A requirement of 1 gpm can be adequate, with storage, for a home. A household with landscaping can require 5 – 10 gpm. Agriculture can require much more for short periods of time.

How long does it take to drill a well?

Most domestic wells take 1 – 4 days, depending on the drilling conditions.

The Influence of Geology on Water Wells

As illustrated by local geologist E.H. Boudreau
Click here

Steve and Ed coordinating the connection of an additional drill pipe

Steve and Ed coordinating a drill pipe connection