Onsite Water Reuse and Dual Plumbing Study
Results and Preliminary Staff Recommendations
Background
● On June 1, 2021, City Council adopted Resolution No. 2021-0166 directing staff to evaluate water conservation policies that could conserve water while promoting green job opportunities
● Part of the Climate Implementation Work Plan
● Study initiated in January 2022
2 Onsite Water Reuse and
Dual Plumbing
Dual Plumbing Feasibility
Study and Dual Plumbing
Ordinance Recommendations
3 Onsite Water Reuse
Treatment Feasibility Study
2022 2023-2024
Dual Plumbing
● System of plumbing installation
to supply both potable and non-
potable water to a building
● Indoor and/or outdoor end uses
● Onsite treatment required for
indoor end uses of greywater and
all end uses of blackwater.
4 Dual Plumbing
● Dual plumbing can be used to
caputre and reuse greywater,
rainwater and/or blackwater.
5 Study Considerations
The focus of the study was the
feasibility of dual plumbing in
commercial (non-residential)
buildings of 100,000 sq ft or
larger.
6 Economic
• Costs for dual plumbing and treatment
• Costs to administer the program
Regulatory
• Existing & Upcoming codes and regulations
Technical
• Requirements for treatment, testing, and inspection
Market Assessment
• Reviewed the number of buildings (100,000sqft) built
and planned in Sacramento
Reviewed 3 Cases Studies
Key Findings
7 Dual Plumbing
Installation Costs
8 • Cost model based on 17
commercial buildings
constructed in California
within the last five years
Cost per area ($/sf) to add dual plumbing to
commercial buildings
Dual Plumbing
Installation Costs
9 Percent increase to total project cost to add dual
plumbing to commercial buildings
Treatment and
Operation
10 • Treatment requirements
and costs are highly
variable depending on
source water and end
use
Program
Administration
11 ● Additional staffing
resources may be
needed for DOU for
initial set up and
ongoing admin of the
program.
● Plan check and cross
connection inspections
can likely be absorbed
within existing staffing.
Regulatory Findings
12 • Current plumbing code
allows for the
installation of rainwater
and grey water reuse
systems.
• SB 966 – upcoming
regulations
SB 966
• Requires the State Water Board to
adopt regulations for onsite treatment
and reuse in buildings.
• Draft regulations are expected August
1, 2022
• Regulations are expected to be
effective December 1, 2022
• Potential County of Sacramento role as
permitting agency.
Testing and
Inspection
13 • Strict public health and
safety requirements
• Regular Cross
connection testing
• Public notification
• Ongoing Water
quality testing
Sacramento’s Market Assessment
13 Commercial Buildings Built
● 100,000 sqft or greater
14 14 Commercial Buildings
● 100,000 sqft or greater
2010-2022 Planning Entitlements
Planned
Commercial Non-
Residential
Buildings by
Building Type
15 Building Type Number of Buildings
100,000 sq ft or greater
Commercial/Retail 7
Office 1
Hotel/Motel 3
Industrial 1
Warehouse 2
Case Studies
16 • San Francisco, Hawaii,
Santa Monica
San Francisco Onsite Water Reuse
Program
• 2012 – Established a voluntary onsite water
reuse program
• 2016 – Required onsite water reuse for
buildings of 250,000 sqft or larger
• 2021 – Required onsite water reuse for
buildings of 100,000 sqft or larger
• City/County Department of Environmental
Health – approves the engineering report,
issues permit to operate, and oversees the
water quality testing.
Preliminary Recommendations
17 Rationale for Recommendations
● Match alternate water
sources with appropriate
non-potable end uses
18 ● State regulations are
expected to be completed
by December 2022.
Sustainable and Resilient
Water Management Just Job Transition
Alignment with upcoming
state regulations
● Alignment with New
Building Electrification
Ordinance
Preliminary
Recommendations
19 Phase 1: Dual Plumbing Ordinance:
• Amend title 15 (Buildings and
Construction) of the Sacramento Code
to require dual plumbing to reuse
greywater in certain new buildings
Preliminary
Recommendations
20 Building Criteria:
• New commercial non-residential
buildings
• 100,000 sq ft or greater
• Specific occupancy groups (based on
plumbing fixture density)
Preliminary
Recommendations
21 Proposed Effective Date of Phase 1:
• Bring forward an Ordinance within 6
of the effective date of SB 966
(expected December 2022)
Building Types
Subject to
Proposed
Requirements
22 Building
Type
Number of
Buildings
100,000 sq ft
or greater
Subject to
proposed
requirements
Commercial
/Retail
7 Office 1
Hotel/Motel 3
Industrial 1
Warehouse 2
Preliminary
Recommendations
23 Phase 2: Onsite Water Reuse Treatment for Grey
and Blackwater
• Phase in potential requirements for onsite
reuse of grey and blackwater after the state
adopts water quality standards for onsite
treatment of non-potable water (per SB 966)
• Proposed effective date of January 1, 2026, to
coincide with the full implementation of the
New Building Electrification Ordinance
Onsite Water Reuse and Dual Plumbing Study
Results and Preliminary Staff Recommendations