Zero Water Footprint & Will-Serve Process


Zero Water Footprint Policy

Water is a finite resource. The City of American Canyon is committed to conserving water as we believe it is our duty to use this precious resource responsibly so that it is here for us to use far into the future.

Zero Water Footprint Policy

As a part of ongoing water conservation efforts in the commercial sector, the City of American Canyon adopted a Zero Water Footprint policy. Also known as ZWF, the primary goal of this policy is that there is no loss in reliability or increase in water rates for existing water service customers due to new demand for water within the City’s water service area.

In order to meet our ZWF standards, Developers must ensure that all new developments offset the amount of increased potable water that will be consumed by their project on a one-to-one basis. As part of the process, Developers are first required to minimize their demand for new potable water by using water efficient fixtures, consuming recycled water for non-potable uses when available, dual plumbing buildings, installing water wise landscaping and irrigation, and other appropriate measures. Once the Developer, working with the City, has refined their plan to minimize potable water needs, the City works with them to evaluate the water footprint of the project and the proposed offset to determine if the project has achieved a ZWF.

There are several ways to meet our ZWF requirements. Depending on the size and scope of the project, a variety of methods may be used. During the development process, the City and Developer work in partnership with each other to identify the most appropriate ZWF methods for offsetting the increase in potable water consumption. These methods might include:

  • Contributing to the City’s existing conservation programs, including our popular Cash-for-Grass turf conversion program, toilet retrofits, and similar community-wide programs.
  • Eliminating an existing public use of potable water by converting it to recycled water, such as city park and landscaping irrigation.
  • Constructing or funding city capital projects that directly result in reduced demand for potable water or increased capacity to produce recycled water, including but not limited to replacing leaking main lines, replacing inefficient water meters, and treatment improvements at the water reclamation facility.
  • Contributing toward the expansion of the City’s reclaimed water system by extending the purple pipeline to locations not currently served by recycled water.Acquiring water supply from another source.

Methodology for Determining Zero Water Footprint and Developing Water Supply Reports(PDF, 153KB)

Napa Junction Phase III

Napa Junction Phase III is a wonderful example of a successful ZWF project. The Canyon Ridge Apartments located on the site are dual-plumbed. This means that every residential unit flushes with reclaimed water. Landscaping throughout the site features drought-resistant plants and reclaimed water irrigation. The irrigation system contains rain sensors that automatically pause irrigation if the system detects rain.

The Developer also extended the reclaimed water pipe (also known as purple pipe) from Green Island Road to the Napa Junction Phase III project site, then through to Main Street Park. This action allowed the City to provide reclaimed water to all the current landscaping contained in and around WalMart, surrounding businesses, the frontage road along Highway 29, and Main Street Park.

All of these actions combined mean that the Developer has provided the ability to discontinue use of valuable potable water in these locations. In turn, that potable water is secured for use in their residential and retail units without a significant impact to current City water supply.


We believe that through our Zero Water Footprint policy, we can effectively manage our supply of fresh water as a sustainable resource, while also protecting our water environment as we work towards meeting future City growth and demand.


Public Works is responsible for management of the City's water supply. As stewards of this finite resource, Engineering staff are responsible for allocating water to City customers and ensuring that we meet the needs of everyone in our water service area.

For development projects, an applicant is required to submit a Will-Serve Application(PDF, 212KB) to Public Works regarding their anticipated water demand and sewer generation rate. The request is reviewed in light of the Zero Water Footprint Policy adopted by the City Council in October 2007, which is defined as:

"No loss in reliability or increase in water rates for existing water service customers due to requested increased demand for water within the City's Water Service Area."

If a project does not have a zero water footprint, a Water Supply Report will be prepared. The Water Supply Report analyzes the request in light of the City's supply and distribution system. It includes the water demand, the capacity fee to be charged to the project, and any conversation or mitigation measures that may be required.

When the Water Supply Report is complete, staff prepares a "Will-Serve" letter, which sets the terms and conditions for receiving water from the City. Once the terms of the Will-Serve letter are agreed to by the applicant, Public Works will send a letter to the Napa County Planning Department confirming that the City will supply water to the project. The Will-Serve letter must be issued prior to approval of a planning entitlement or a building permit.