Excerpt from VWWM §1.3.6

A letter from a Water Purveyor declaring that the purveyor’s water system has the necessary water capacity available to supply the domestic and firefighting requirements for the project or service area identified in the letter. The Water Availability Letter must be signed by a member of the purveyor’s Board of Directors or General Manager and contain the following:

1. A map of the project or service area served by the water system showing parcels served along with their Assessor Parcel Numbers (APNs).
2. A description of the existing (or planned) system and all planned changes to the existing system that will be made to provide service to the project or service area identified in the letter.
3. A completed Waterworks Manual Compliance Worksheet (Appendix D) for the system and each pressure zone in the system.

1. The maximum day average demand (Q0), required domestic storage volume (V0) and number of service connections (N) may be calculated by using either the methods described in this manual or commonly accepted engineering practices.

1. A summary of all areas not in compliance with this manual and the plan for bringing the water system into compliance with this manual.
2. The engineering analysis prepared and stamped by a civil engineer which was used to prepare the Waterworks Manual Compliance Worksheet(s) and includes the following:

1. Method and calculations for determining maximum day average demand (Q0) and required domestic storage volume (V0), for both existing and maximum number of service connections (N).
2. Method and calculations for determining compliance with the peak hour demand requirements of this manual.
3. Method and calculations for determining compliance with the system reliability requirements of this manual.
4. Method and calculations for determining compliance with the emergency requirements in this manual.

In the case of Water Purveyors classified as Urban Water Suppliers under the Urban Water Management Planning Act, the adoption of a current Urban Water Management Plan that has been accepted by the State Department of Water Resources will satisfy the requirement for submission to and acceptance by the County of a Water Availability Letter (WAL).

More information on methods and procedures that can be used to prepare a WAL can be found in the Ventura County Waterworks Manual (VCWWM) 2nd Edition .The VCWWM establishes the minimum acceptable standards for the design and construction of additions or changes to existing water supply facilities in the unincorporated areas of Ventura County of Ventura and for the purpose of County or County-dependent special district approvals.

The Waterworks Manual Compliance Check sheet can be downloaded here.

In September 2014, notice was given to Ventura County Water Purveyors of the Water Availability Letter requirement and they have been give the opportunity to submit a WAL. A list of currently approved WALs or UWMP can be found on our Will Serve Letter Page. To obtain a copy of this notice please click here.

For list of Water Purveyors in Ventura County, Click here.

Water Purveyor Search: Here

List of Water Purveyors

A current list (as of 09/08/2015) of UWMP Approved Water Purveyors is listed below.

Water Purveyors with Water Availability Letters accepted by Ventura County Public Works Agency:

(Current as of December 30, 2020)

* WAL accepted with conditions, contact PWA Development & Inspection Services for Conditions of Acceptance. Will Serve Letters are not currently being accepted by these purveyors.

A Will-Serve Letter is an agreement/assurance between a Ventura County resident and the water purveyor to provide water service. A WSL approved by the Public Works Agency is required for a property owner to obtain a Building Permit from the Resource Managment Agency.

WSLs will not be accepted by the Public Works Agency unless one of the following items are met:

• There is an accepted Water Availability Letter on file with the County of Ventura Public Works Agency Development & Inspection Services Division; or
• The Water Supplier has an approved Urban Water Management Plan(UWMP) with the State of California. A list of approved UWMP Water Suppliers can be found below.

If you meet either of the two requirements above then a WSL may be submitted to the PWA Development and Inspection Services counter for review. A review will include a verification of available connections and the water purveyors ability to provide service.

All will serve letters submitted shall include, at a minimum, the following information:

• Project size
• Description of Project, indicating if the project is existing or a new connection.
• An accounting of Will-Serve Letters issued compared to number of unused services remaining.
• New development or existing development
• APN
• Type of Development
• Date
• Letterhead from Retail Water Purveyor ( or Wholesale Water District if applicable)
• Signature from a representative of the purveyor having authority
• Address
• Allocations used and remaining
• Zone (if applicable)