Water Neutrality Guidebook

Process for Demonstrating Water Neutrality

For projects requiring planning entitlement approval (use permit): Complete the Water Neutrality Calculator (steps 1-5) as part of the submittal to determine the initial new water demand/off set requirement. The specific details of how water neutrality will be met (e.g. offset credit implementation/which measures will be used) are not required during planning entitlement submittal. When the project is submitted for a building permit, submit the calculator (steps 1-5, updated as needed) and offset credit calculations.  

For projects that require a building permit only (no use permit): Complete the Water Neutrality Calculator (steps 1-5) and offset credit calculations at the time of building permit submittal.

Step 1: Obtain Baseline Water Demand for the subject property.

Staff to provide the applicant with the existing property’s Baseline Water Demand which is the average water use over the previous five-years from the date the building permit application was submitted. Please email utility@fostercity.org to obtain the baseline water demand.

Step 2: Calculate  a Projected Water Demand

Projected water demand is the estimated water demand to be used by the development once completed. For indoor water demand, the factors provided in the Water Capacity Study of the Foster City Housing and Safety Element (Appendix D of the EIR) may be used until a more recent study is available.  For outdoor water demand, please refer to the Outdoor Efficiency Checklist and the EMID Code Chapter 8.80 Outdoor Water Conservation in Landscaping. Please see the Technical Guideline document for instructions and information on water demand factors. 

Step 3: Calculate allocations for water conservation credit

Allocations are separated into indoor and outdoor, based on either demand factors or outdoor maximum applied water allowance (MAWA) . Allocations are the quantities of water that a site should use, based on similar sites and uses. For indoor water demand, the factors provided in the Water Capacity Study of the Foster City Housing and Safety Element (Appendix D of the EIR) may be used until a more recent study is available.  For outdoor water demand, please refer to the Outdoor Efficiency Checklist and the EMID Code Chapter 8.80 Outdoor Water Conservation in Landscaping.

Step 4: Calculate water conservation credit

The sum of the indoor and outdoor water allocations minus the baseline water demand for actual water use only (inactive or partially active meter using demand factors, etc. are not eligible). If a site is using more water than the allocation, no water conservation credit is given. 

Step 5: Calculate New Water Demand (Off Set Requirement)

The New Water Demand is the projected demand minus the baseline water demand and takes the water conservation credit into account for developments that are already taking action to become more water efficient. The new water demand is water demand above current usage and must be off set. If the new water demand to be off set is zero, EMID will monitor the site to ensure the baseline water demand is not exceeded.

Projected water demand – (baseline water demand + water conservation credit) = new water demand (off set requirement)

If a project (new development) site is estimated to use more water than the previous site, the new water demand must be off set.  Please see off set measure examples below. 

For questions please contact the Public Works Engineering Division at 650-286-3270.

Water conservation measures are continually advancing, and applicants are encouraged to implement innovative strategies, provided they demonstrate measurable water savings, as certified by a licensed engineer or landscape architect. Below are possible categories for water off water neutrality compliance set measures to be completed on the project site of within the EMID service area: 

• Indoor water saving/efficiency
• Outdoor water saving/efficiency/restoration
• Building system/process optimization/efficiency
• On site water generation

Some examples include: 

• changing existing faucets to low flow faucets
• installation of dual flush or low flush toilet
• removal of lawn and replacement with climate friendly drought tolerant landscaping
• closed loop water recycling system in a laundry facility
• gray water system
• rainwater harvesting system

An applicant may request an offset credit for measures performed on or off-site up to five years prior to submission of project application, or July 1, 2023, whichever is most recent. Please see the Water Neutrality Guidelines for additional details. 

With regard to building and landscape design and operation, the applicant would still be required to comply with existing EMID and City of Foster City regulations including:

• Foster City Code Chapter 13.12 Stormwater Management and Discharge Control
• EMID Code Chapter 8.60 Water Conservation and Rationing
• EMID Code Chapter 8.70 Indoor Water Use Efficiency
• EMID Code Chapter 8.80 Outdoor Water Conservation in Landscaping

2020 Urban Water Management Plan for Estero Municipal Improvement District   

BAWSCA Per Capita Water Use
Appendix D: Water Capacity Study of the Foster City Housing and Safety Elements Update EIR
Foster City Housing and Safety Elements Update- Responses to Comments Document

EMID water customers have access to various rebates to assist with water reduction.

Please visit the Water Conservation Rebate Programs page.

The City of Foster City and the Estero Municipal Improvement District Board of Directors adopted the Water Nuetrality Growth Ordinance that went into effect on May 1, 2023.  See Chapter 8.90 Chapter 8.90, Water Neutrality Growth within Title 8, Water and Sewer Service of the EMID Code.

History:

On August 5, 2024, the President and Members of the Estero Municipal Improvement District (EMID) Board of Directors adopted and amendment to the Water Neutrality Ordinance which included amendments relating to water conservation offset credit to allow applicants to receive credit for water conservation measures undertaken prior to project application submission and other various clarifying revisions.  The amendments are in effect 30 days after the adoption of the Ordinance. (August 5, 2024 staff report link and Ordinance link)

On May 22, 2023 the President and Members of the Estero Municipal Improvement District (EMID) Board of Directors approved Resolution 2023-48 approving the Water Supply Assessment (WSA) Report for the Final Environmental Impact Report (EIR) for the Housing and Safety Elements Update.

A WSA is required for a proposed residential development of more than 500 dwelling units. The requirements for the WSA is described in the California Water Code Sections 10910 through 10915, amended by the enactment of Senate Bill 610 (SB 610) in 2002. SB 610 requires an assessment of whether EMID total projected water supplies available during normal, single-dry and multiple-dry water years, during a 20-year projection, are sufficient to meet the projected water demand associated with the 2023-2031 Housing Element, in addition to existing and planned future uses in the EMID service area (see Water Code Section 10910(c)(3)).

The WSA concluded that there is not “sufficient water supply” (per Government Code 664737.7 (a)(2)) available to meet the demands of the 2023-2031 Housing Element, in addition to the existing and planned future uses evaluated in this WSA, during single-dry and multiple dry water years within a 20-year projection. Water reduction strategies were identified in the WSA such as a Water Neutrality Growth Policy.  (May 22, 2023  staff report link)

May 15, 2023 the EMID Board adopted Resolution No. 3721 approving the Water Supply Assessment (WSA) report for the Final Environmental Impact Report (EIR) for the Housing.  (May 15, 2023 for staff report link)

 On May 1, 2023 EMID Board approved an Ordinance adding a new Chapter 8.90, Water Neutrality Growth within Title 8, Water and Sewer Service of the EMID code. (May 1, 2023 staff report link)

On March 20, 2023 EMID Board approved Resolution No. 3713 directing staff to prepare an Ordinance implementing a Water Neutrality Growth Policy framework, as a long-term water demand management measure.  (March 20, 2023 staff report link)