Small Water Systems


State Water Resources Control Board Guidance Document for Public Water Systems & Their Affected Communities

What is a small water system?

A small water system is defined as water for human consumption that has 15 or more service connections or regularly served at least 25 individuals at least 60 days out of the year. Nevada County through our Local Primacy Agency, under contract with the State Water Resources Control Board, ensures that small water systems deliver safe, adequate, and dependable potable water.

Water systems are divided into the following categories:

  • Community Water System: A public water system that has 15 or more service connections used by year-long residents OR regularly serves at least 25 year-long residents of the area served by the system.
  • NonTransient-Noncommunity Water System: A public water system that is not a community water system that regularly serves at least 25 of the same persons during six months of the year.
  • Transient-Noncommunity Water System: A non-community water system that does NOT regularly serve at least 25 of the same persons during six months of the year.
  • State Small Water System: A system for the provision of piped water to the public for human consumption that serves at least five, but not more than 14, service connections and does not regularly serve drinking water to more than an average of 25 individuals daily for more than 60 days out of the year.

In order to apply for a Small Water System, please complete the following:

  • First read through the Requirements for New Public Water Wells PDF.
  • A Preliminary Technical Report shall be submitted to Nevada County Environmental Health prior to doing any water-related construction.
  • Submit an application to drill a Class II well to Nevada County Environmental Health along with any applicable fees.  The application should include a well site control zone with all required setbacks, design plans and specification sheets and documentation for compliance with the California Environmental Quality Act (CEQA).
  • Apply for a major water plan check and submit the following documents, along with the applicable fees:
    • Design drawings of proposed facilities drawn to scale, showing location, size, and construction material.
    • The estimated Max Day Demand (MDD) and Peak Hourly Demand (PHD).
    • A source water assessment and description of each source of water proposed for use.  
    • Information that demonstrates how the system proposes to reliably meet 4 hours of PHD using available source capacity and distribution reservoirs.  
    • Technical, Managerial and Financial (TMF) Capacity Assessment.  
    • Well Completion Report.
    • Bacteriological Sample Site Plan and Emergency Notification Plan.
    • Fill out the appropriate Application, links for applications can be found below.
    • Detailed project description.

For more information, please see below or refer to our FAQ page. 

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