Sacramento Regional County Sanitation District: Wastewater and Environmental Services

The Sacramento Regional County Sanitation District (SRCSD) is the public agency responsible for collecting, treating, and disposing of wastewater generated across a large portion of Sacramento County and portions of adjacent jurisdictions. Operating one of the largest wastewater treatment facilities on the West Coast, the District manages a regional infrastructure system that directly affects water quality in the Sacramento and American rivers. This page covers the District's scope, operational structure, the scenarios it governs, and the boundaries between its authority and that of other utilities and agencies.

Definition and scope

SRCSD is a county sanitation district formed under California Health and Safety Code, Division 7 (California Health and Safety Code §§ 4700–4856), which authorizes counties to establish sanitation districts as independent special districts. The District's primary service area covers unincorporated Sacramento County along with portions of the cities of Sacramento, Elk Grove, Citrus Heights, Rancho Cordova, Folsom, and several smaller communities. The Sacramento County Board of Supervisors acts as the District's Board of Directors, providing governance oversight.

The District's core asset is the Sacramento Regional Wastewater Treatment Plant (SRWTP), located in Elk Grove near the intersection of Dwight Road and Elkhorn Boulevard. The plant has a permitted treatment capacity of approximately 181 million gallons per day (MGD) under its National Pollutant Discharge Elimination System (NPDES) permit issued by the Central Valley Regional Water Quality Control Board (CVRWQCB). Treated effluent is discharged into the Sacramento River under strict water quality standards governing nitrogen, pH, temperature, and biochemical oxygen demand.

For residents and property owners looking for broader context about how the District fits into regional governance, the Sacramento Metro Authority index provides an overview of the area's interconnected public agencies and special districts.

How it works

Wastewater flows from homes, businesses, and industrial facilities through a network of local collection systems — owned and operated by individual cities or local utility districts — before entering SRCSD's regional interceptor system. The District does not own local sewer lines within most city limits; it owns and operates the trunk interceptors and the treatment plant.

The treatment process at SRWTP follows a multi-stage sequence:

1. Preliminary treatment — Screens and grit chambers remove large solids and abrasive particles from raw influent.
2. Primary treatment — Sedimentation basins allow suspended solids to settle, removing roughly 50–60% of suspended material.
3. Secondary treatment — Activated sludge biological processes reduce dissolved organic material and oxygen demand.
4. Tertiary/advanced treatment — Filtration and disinfection (using sodium hypochlorite and ultraviolet systems) bring effluent to NPDES permit standards before discharge.
5. Biosolids processing — Digested solids are dewatered and land-applied or otherwise beneficially reused under U.S. EPA Part 503 biosolids regulations (40 CFR Part 503).

The District funds operations through service charges billed to property owners within the service area, collected on the annual Sacramento County property tax statement. Capital projects are financed through revenue bonds and state revolving fund loans administered by the California State Water Resources Control Board (SWRCB).

Common scenarios

Residential connection requests: When a property within unincorporated Sacramento County or a contracting city seeks a new sewer connection, the property owner applies through the local city or county agency, which then coordinates capacity allocation with SRCSD. The District evaluates whether existing interceptor and plant capacity can accommodate additional flow before a permit is issued.

Industrial pretreatment compliance: Businesses discharging industrial wastewater — including food processors, metal finishers, and medical facilities — must comply with SRCSD's Industrial Pretreatment Program, which implements federal categorical pretreatment standards under 40 CFR Part 403. Facilities must obtain a discharge permit and submit periodic self-monitoring reports.

Permit renewals and regulatory negotiations: SRCSD's NPDES permit is subject to renewal every 5 years under the Clean Water Act (33 U.S.C. § 1251 et seq.). Permit renewals typically involve negotiation with the CVRWQCB over effluent limits — particularly nitrogen limits, which have been a prolonged regulatory issue for the Sacramento region given the Sacramento River's role as a downstream drinking water source.

Wet weather overflow events: During significant storm events, groundwater infiltration and inflow can approach or exceed the 181 MGD plant capacity, requiring operational adjustments and, in some cases, regulatory notifications under the District's Sanitary Sewer Overflow (SSO) reporting obligations.

Decision boundaries

SRCSD's authority is geographically and functionally bounded. Understanding what falls inside and outside its scope prevents misdirected inquiries.

Inside scope:
- Regional interceptor sewer conveyance
- Wastewater treatment at SRWTP
- Industrial pretreatment permitting for dischargers into the regional system
- Biosolids management and land application
- Regional service charge administration

Outside scope — not covered by SRCSD:
- Local collection systems (lateral sewers, neighborhood mains) within city limits — those are owned by cities such as Sacramento, Elk Grove, Folsom, Rancho Cordova, and Citrus Heights
- Stormwater drainage and flood control — governed by the Sacramento Area Flood Control Agency (SAFCA) and county drainage districts
- Drinking water supply — administered by the Sacramento Municipal Utility District (SMUD) for electricity, and by Sacramento County Water Agency or individual city utilities for water
- Wastewater treatment for areas outside the District's service boundary, including portions of Yolo County ([/yolo-county-government]) or Placer County ([/placer-county-government]), which have independent treatment facilities

The District's geographic coverage also does not extend to unincorporated communities served by septic systems rather than sanitary sewers; those systems are regulated at the local level under Sacramento County Environmental Management Department authority, not SRCSD.

A practical contrast: a homeowner in unincorporated Sacramento County whose sewer lateral backs up should contact Sacramento County's Department of Utilities for local line issues, not SRCSD. SRCSD becomes the relevant agency only when flow enters the regional interceptor system downstream of the local collection point.

References

• Sacramento Regional County Sanitation District (SRCSD) — Official Site
• Central Valley Regional Water Quality Control Board (CVRWQCB)
• California State Water Resources Control Board (SWRCB)
• U.S. EPA National Pollutant Discharge Elimination System (NPDES)
• U.S. EPA 40 CFR Part 503 — Biosolids Standards
• U.S. EPA 40 CFR Part 403 — Industrial Pretreatment Program
• Clean Water Act, 33 U.S.C. § 1251 et seq. — GovInfo
• California Health and Safety Code §§ 4700–4856 — County Sanitation Districts