Backflow Testing in Stanislaus County, California
California-certified backflow testing across every major Stanislaus County water purveyor, dispatched from our Modesto headquarters with same-week scheduling.
- CCL: #1062017
- AWWA Backflow Tester Cert.: #15112
- AWWA Specialist Cert.: #03373
- Cross-Connection Specialist on staff
- 9 Stanislaus cities served
Serving: Modesto, Turlock, Ceres, Oakdale, Patterson, Riverbank, Waterford, Hughson, Newman.
Do I need backflow testing in Stanislaus County?
If your property sits on a City of Modesto, Turlock, Ceres, Oakdale, Patterson, Riverbank, Waterford, or Newman water connection and has a backflow prevention assembly (RP, DC, PVB, or SVB) between the meter and your irrigation, fire line, boiler, or process water, you are responsible for an annual test. You also need a test after any new installation, repair, or relocation.
“Owners must have the devices tested each year by a certified tester to ensure they are working properly, and the results must be reported to the City.”
The scope is large. The City of Modesto Water Services Division alone operates over 75,000 water service connections across roughly 1,000 miles of potable pipeline, and every commercial and industrial account with a cross-connection risk carries a device that has to be tested every year.
Not sure if this applies to your property? Call (800) 684-8346 and we will tell you over the phone whether your service address has a registered device.
Water purveyors in Stanislaus County requiring annual testing
Each city runs its own cross-connection control program under California state authority. The platforms, deadlines, and ordinance sections differ, so test reports have to be filed with the right utility using the right method.
| Purveyor | Service Area | Governing Rule |
|---|---|---|
| City of Modesto Utilities | Modesto, portions of Ceres, Del Rio, Empire, Grayson, Salida, Turlock | Modesto Municipal Code, Cross-Connection & Backflow Control (program page) |
| City of Turlock Municipal Services | Turlock | Turlock Municipal Code § 6-6 |
| City of Ceres | Ceres | Ceres Municipal Code Chapter 13.28 |
| City of Oakdale | Oakdale | Oakdale MC, Backflow & Cross-Connection Control |
| City of Patterson | Patterson | Patterson Backflow Prevention Device Annual Test Program |
| City of Riverbank | Riverbank | Riverbank Municipal Code § 52.35 |
| City of Waterford | Waterford | Waterford Backflow & Cross-Connection Regulations |
| City of Newman Public Works | Newman | Newman Municipal Code Chapter 11.05 (Water Service Regulations) |
“The city may shut off service to any premises and may physically disconnect the customer's piping from the city's water distribution system if a backflow prevention device required by this section is not installed, tested, and maintained as required.”
Note: Modesto Irrigation District (MID) and Turlock Irrigation District (TID) deliver wholesale and raw agricultural water, not retail drinking water, so their customers are governed by the city utility program tied to the premise, not by MID/TID directly.
How our testing process works
- 1
Schedule
Call (800) 684-8346, email, or use the scheduling form. Same-week availability across Stanislaus County is typical.
- 2
On-site test (10 – 20 minutes)
Most residential and small commercial devices test with a full water shut-off. We isolate the assembly, run the certified test procedure, and record readings on the test form.
- 3
If a device fails, clear options
If possible, we walk you through repair versus replacement on the spot, with pricing before any work starts. We avoid proceeding without your approval.
- 4
Report filed within 24 hours
We submit the certified test report form directly to your purveyor using the method they require (email for Modesto, Turlock, Ceres, Patterson; direct to Public Works for Riverbank, Oakdale, Waterford, and Newman). You get a copy with the invoice.
- 5
Annual reminder
We track your anniversary date and reach out ahead of time so you never end up with a non-compliance notice from the city.
Devices we test
ASSE 1013
Reduced Pressure Assembly (RPA / RPZ)
The highest-hazard device class. Required for chemigation, boiler feed, industrial process water, and fire lines with chemical additives. Typical at Modesto food plants and Turlock dairies. See a reference Febco RP spec.
ASSE 1015
Double Check Valve Assembly (DCVA)
Lower-hazard applications: residential fire lines, commercial irrigation without chemical injection, and many HOA landscape meters. Most common device on Modesto and Turlock residential accounts.
ASSE 1020
Pressure Vacuum Breaker (PVB)
Above-ground irrigation backflow protection. Very common on Oakdale, Riverbank, and Waterford landscape accounts and small-acreage orchards on city water.
ASSE 1056
Spill-Resistant Vacuum Breaker (SVB / SRVB)
Modern variant of the PVB with reduced nuisance spill. Common retrofit on Ceres and Patterson residential irrigation where a legacy PVB has reached end of life.
California and federal compliance context
“All backflow prevention assemblies are to be tested annually at the owner's expense.”
400+
documented backflow incidents in the United States, 1970 – 2001, per the EPA Cross-Connection Control Manual (816-R-03-002).
Additional authorities: the AWWA M14 Manual, 5th ed. governs recommended practice, the USC Foundation for Cross-Connection Control and Hydraulic Research (FCCCHR) Manual 10th ed. defines the approved field test procedures, and CA Health & Safety Code § 116800 grants local health agencies program authority over cross-connections.
Cities we serve in Stanislaus County
Modesto
County seat. The City of Modesto runs over 75,000 water service connections; E. & J. Gallo Winery, Stanislaus Food Products, Doctors Medical Center, and Memorial Medical Center are concentrated RP-assembly accounts.
Turlock
Staggered annual deadlines on March 1, June 1, and September 1. Emanuel Medical Center and the surrounding dairy corridor drive commercial RP demand under Turlock Municipal Code § 6-6.
Ceres
Annual testing is due by May 1 under Chapter 13.28. Bronco Wine Company's production campus on Bystrum Road is the best-known local high-volume water account.
Oakdale
Cowboy Capital of the World. A heavy mix of Oakdale Irrigation District orchard parcels and city water residential accounts means DCVA and PVB volume dominate here.
Patterson
Apricot and almond processing hub on the west side. Patterson Public Works will test devices itself if an owner misses the annual deadline, so staying ahead of the notice matters.
Riverbank
Annual testing due by March 15 under Municipal Code § 52.35. The ordinance authorizes water service shut-off for non-compliance, so missed deadlines carry real consequences.
Waterford
Smaller ag-adjacent system on the Tuolumne River. City regulations explicitly cover RPA, DCVA, and PVB assemblies and cite CCR Title 17 as the framework.
Hughson & Newman
Small city systems in the Stanislaus dairy and westside ag corridors. We test residential and small commercial devices here; schedule-ahead is recommended since purveyor response times run longer.
Our credentials
California
CCL #1062017
Active contractor state license.
Backflow tester
AWWA Backflow Tester Cert. #15112
AWWA-certified backflow tester in good standing.
Specialist
AWWA Specialist Cert. #03373
Cross-Connection Control Specialist certification.
Ownership
Family-owned
Jesse Cuevas, owner and lead tester.
Our lead technician is Jesse Cuevas, a Cross-Connection Specialist with 13+ years in backflow prevention, installation, testing, and repair. Every test we perform is run by a tester credentialed under AWWA and documented with the exact gauge, serial, and device readings your purveyor needs on file. We do not sub-contract field work out of the county.
Frequently asked questions
How often is backflow testing required in Stanislaus County?
Every major water purveyor in Stanislaus County requires an annual test, aligned with the California State Water Resources Control Board Cross-Connection Control Policy Handbook (effective July 1, 2024). Testing is also required after installation, relocation, or repair of any assembly.
Which water purveyors in Stanislaus County require annual testing?
The City of Modesto, City of Turlock (MC § 6-6), City of Ceres (MC Chapter 13.28), City of Oakdale, City of Patterson, City of Riverbank (MC § 52.35), City of Waterford, and City of Newman all run cross-connection control programs with annual testing requirements. MID and TID are wholesale and raw-water suppliers rather than retail drinking-water CCC authorities.
What happens if my device fails the test?
We walk you through the failure mode on site, quote the repair (commonly a rubber kit, check, or relief valve replacement), and schedule the retest. We avoid starting work without your approval. Under Riverbank MC § 52.35 and similar ordinances, the purveyor can ultimately shut off water service for uncorrected failures, so quick turnaround matters.
Who is legally allowed to test backflow devices in California?
Only a backflow prevention assembly tester certified by AWWA or the USC FCCCHR and listed on the relevant purveyor's approved tester roster. Our lead specialist holds AWWA Backflow Tester Cert. #15112 and AWWA Specialist Cert. #03373, and City Certified Backflow Prevention carries CCL #1062017.
How do I submit my test report to the City of Modesto?
The City of Modesto Water Services program accepts backflow test reports by email to WaterBackflow@modestogov.com (phone 209-342-2246). We file the certified test report form on your behalf within 24 hours of the test and send you a copy with the invoice.
Does an agricultural chemigation setup on my Stanislaus irrigation account need backflow testing?
If the chemigation point is on a City of Modesto, Turlock, Ceres, Oakdale, Patterson, Riverbank, Waterford, or Newman drinking-water connection, yes: chemigation is a classic high-hazard case that requires a reduced-pressure (RP) assembly and annual testing. If it is strictly on a raw MID or TID canal connection with no drinking-water tie-in, the requirements differ and we can confirm by phone.
Annual deadlines in Stanislaus County are enforced by your city utility. Non-compliance can result in water service shut-off under Riverbank MC § 52.35 and similar ordinances.
Mon – Sat, 7:30 AM to 5:00 PM. Emergency response available.
Sources and authorities cited on this page
California state authority. CA SWRCB Cross-Connection Control Policy Handbook (CCCPH), CA Health & Safety Code § 116800, CCR Title 17 § 7605 (legacy, repealed 2024-07-01).
Federal. EPA Cross-Connection Control Manual (816-R-03-002), CDC MMWR surveillance for waterborne outbreaks.
Standards bodies. AWWA M14, 5th ed., USC FCCCHR, ASSE International.
Stanislaus County purveyors. Modesto Cross-Connection Program, Modesto Water Services, Turlock Water Quality, Ceres Cross-Connection Program, Oakdale MC Backflow ordinance, Patterson Annual Test Program, Riverbank CCC Program, Riverbank MC § 52.35, Waterford Backflow Regulations, City of Newman Public Works, Newman MC Chapter 11.05.