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Our Mission, Organization, Facts, and History

Our Mission

To safely and responsibly collect and treat wastewater for the Tri-Cities while protecting human health and improving the environment in a way that benefits our customers, employees and the community.

Read more about how we accomplish our Mission

Our Organization

See our organizational chart here.

Our Employee Union's Mission:

Union Sanitary District is synonymous with quality work. Our highly skilled and qualified labor force is the cornerstone to the overall public health and success of the communities we serve. Through hard work and dedication, we provide customers with value for their dollar.

Our Sewer System Management Plan (SSMP) can be found HERE.
The SSMP is updated twice a year - last updated 5/24/2016.

District Facts

When was USD founded? May 27, 1918

What area does USD serve?
(annexed areas)
City of Fremont 36.4 sq.mi.
City of Newark 13.8 sq.mi.
City of Union City 9.9 sq.mi.
Total 60.2 sq.mi.

How many people are served by USD?

Fremont 229,324
Newark  44,733
Union City 72,952
Total population served (January 2016 California Dept. of Finance demographics) 347,009
What types of customers are served? (as of 6/16)
Type of customer
No. of Connections
Domestic/Residential living units
Commercial parcels
Industrial  parcels

How many miles of sewers does USD maintain? 811

How many gallons of wastewater are treated each day?
2015 Average Daily Flow: 21.85 million gallons

What type of treatment does the plant provide?
Primary: which uses screening and sedimentation
Secondary: which uses activated sludge

Who are the major industrial dischargers in the area served by USD and what is their flow (gallons per day)? (6/16)

Tesla Motors
Western Digital - Fremont #1
Seagate #3
Lam Research/CA3
U.S. Pipe & Foundry
Washington Hospital
Kaiser Hospital
Thermo Fisher Scientific

Silevo Inc.


How many people does USD employ? 137 (July 2016)

What is USD's annual operating budget? $34,534,433 (FY 2017)
USD's Fiscal Year 2016: July 1, 2016 through June 30, 2017

What is the annual service charge for a single family? $380.05 (as of July 1, 2016))

What is the current capacity fee? $6,421.17 equivalent dwelling unit (FY 2017)

Historical Information

1918 Union Sanitary District (USD) founded; first Board of Directors meeting

1923 District reorganized under Sanitary District Act of 1923

1924 First two connections made to USD system

1949 Niles Sanitary District becomes part of USD

1954 Decoto Sanitary District annexed to USD

1956 Irvington Sanitary District becomes part of USD

1962 City of Union City joined USD service area

1974 East Bay Dischargers Authority (EBDA) JPA formed; USD contracted for
.........19.7 mgd of capacity in outfall to deep portion of San Francisco Bay.

1981 Alvarado Wastewater Treatment Plant (WWTP) completed
.........Abandoned Newark & Irvington plants
.........Transport system and EBDA outfall put into operation

1988 Alvarado WWTP expansion completed

1990 Treatment Plant Facilities Plan completed

1994 District-wide Master Plan completed and EIR certified

1996 Alvarado Wastewater Treatment Plant Upgrade construction complete (30 mgd)

1997 Reorganization into a Team-based organization

2001 Consolidated USD Administration, Corp Yard and Wastewater Treatment Facilities at one location in Union City.


The Union Sanitary District is an independent special district which provides wastewater collection, treatment and disposal services to the residents and businesses of the cities of Fremont, Newark and Union City, in Southern Alameda County, California. Independent special districts are voted into existence by the citizens they serve and are sanctioned under California law to perform specific local government functions within certain boundaries. The District was formed in 1918 and reorganized under the Sanitary District Act of 1923. It derives its authority in the California Health & Safety Code (Sections 6400-6830). The District is governed by an elected Board of Directors which is accountable to the public. The Directors are members of the community they represent. The District recovers the cost of their service delivery through rates imposed on users of the service. The District is independently audited and subject to state and public scrutiny.

Other special districts in Alameda County provide services such as water, fire service, mosquito abatement, recreation, parks and hospital services