Backflow Prevention Program | City of Hamilton

The City's Prevention of Backflow By-law 10-103 ensures that the City of Hamilton drinking water quality and distribution system is protected from each industrial, commercial, institutional or multi-residential property. Under backflow conditions, contaminates from these properties could enter the drinking water system when a property is not sufficiently backflow protected.

The By-law affects all:

Industrial properties
Commercial properties
Institutional properties
Multi-residential properties four stories or higher

What is Backflow?

The flow of water through a pipe in a direction opposite to that which is normal or intended. When this occurs, contaminates may be drawn back into the City’s water distribution system unless prevented by a backflow preventer.

Two types of backflow that can occur:

Backpressure is backflow that can be caused when the pressure within the private water supply system is greater than the water pressure supplied by the City’s water distribution system. Can be caused by things such as booster pumps located on the property.
Backsiphonage is backflow that can be caused by a pressure drop in the City’s water distribution system which could draw water from the private property back into the City’s water distribution system. Can occur due to a watermain break, or excessive demand on the system such as fire fighting.

What is a Backflow Prevention Device?

A Backflow prevention device is a mechanical device installed on a water service downstream of the water meter to prevent backflow.

Property Owner

Backflow Survey Requirements

Property owners with a water service line entering their property that is 38 mm (1.5 inches) in diameter or smaller need to complete a Self Assessed Survey once every 5 years. This will determine the level of backflow risk associated with your property. If there is more than one business located on your property a survey must be completed for each individual business.

Download & Completed the Backflow Self Assessed Survey(PDF, 3.15 MB)

Email the completed survey to [email protected]
Send the completed survey by mail to:
City of Hamilton
Backflow Prevention Program
330 Wentworth Street North
Hamilton, ON L8L 5W2

If you require more information to complete your Self Assessed Survey call Customer Service at 905-546-2489.

Property owners with a water service line entering their property that is 50mm or larger or are deemed by the City of Hamilton through the Self Assess Survey to require a completed Cross Connection Survey.

Hire a contractor from the approved City of Hamilton list of contractors. The contractor will complete a Cross Connection Survey(PDF, 409.22 KB) to determine the hazard level associated with your property.

Submit an original signed copy of the Cross Connection Survey and the fee within 14 days of completing the survey in person or by mail to:
City of Hamilton
Backflow Prevention Program
330 Wentworth Street North
Hamilton, ON L8L 5W2

You will receive a Cross Connection Survey Acknowledgement by mail from the City of Hamilton. It will identify the hazard level based on the completed Cross Connection survey and determine the appropriate backflow prevention device required for your property.

Learn More About

Backflow Prevention Devices

Installation Process

Relocating Device

Common Prevention Devices

Program Fees

Steps to Install Backflow Device

A Building Permit is required for all backflow device installations. You can purchase the permit from at City Hall, 71 Main Street West, 3rd Floor, Hamilton.
You will need to have your contractor install the backflow prevention device and carry out the initial test.
Call the Building Division at 905-546-2720 to schedule your backflow prevention device inspection. The inspector will come out after the installation and initial test have been completed.
Submit the Initial Backflow Device Test Report and the fee within 14 days of completion to the City of Hamilton Backflow Prevention Program at 330 Wentworth Street North, Hamilton.

Complete Double Check Value Assembly (DCVA) Device(PDF, 85.13 KB)

Complete Reduced Pressure (RP) Device(PDF, 140.62 KB)

The property owner will receive a Backflow Device Test Acknowledgment by mail from the City.

All backflow prevention devices must be tested every year after installation.

Do you need to relocate or install a Moderate Hazard backflow device from a chamber to inside of a building?

Relocate or Install Backflow From Chamber to Inside Building Request Form(PDF, 252.52 KB)

Submit to:
Backflow Prevention Program
330 Wentworth Street North
Hamilton, Ontario L8L 5W2

Reduced Pressure Zone Assembly

Also known as RP
Has two independently acting check valves separated by a reduced pressure zone
Installed as a unit between two shut off valves
Each check valve is fitted with a test cock for periodic testing.
Can be used for health hazards such as toxic material and severely hazardous connections such as in hospitals and morgues

Reduced Pressure Detector Assembly

Also known as RPDA
Has two independently acting check valves separated by a reduced pressure zone
Installed as a unit between two shut off valves
Each check valve is fitted with a test cock for periodic testing.
Can be used for health hazards such as toxic material and severely hazardous connections such as in hospitals and morgues

Double Check Valve Assembly

Also known as DCVA
Has two internally loaded check valves, force-loaded or internally weighted
If one check valve fails to close the other will prevent backflow
Each check valve is fitted with a test cock for periodic testing
Can be used for all non-health hazards (non-toxic) connections such as fire sprinkler and irrigation systems.

Double Check Detector Assembly

Also known as DCDA
Has two internally loaded check valves, force-loaded or internally weighted
If one check valve fails to close the other will prevent backflow
Each check valve is fitted with a test cock for periodic testing
Used for Moderate hazard Fire service connections.

Service	Fee (HST included)
Self Assessed Survey Fee	Free
Cross Connection Survey Fee	$221.37 per form
Test Report Fee	$73.72 per test
Backflow Prevention Device Inspection - Regular Hours	$185.81
Backflow Prevention Device Inspection - After Hours	$255.09
Backflow Prevention By-law Contractor Registration Fee	$186.72

Backflow Program Contractors

Register as a Contractor

There are four categories of contractors that can register under the Backflow Prevention program to carry out functions listed in the Backflow Prevention By-law including:

Plumbing companies
Sprinkler and Fire Protection Installers
Professional engineers
Corporations

The City of Hamilton will issue one permit number per company. The Master Plumber or P. Eng. must do all registrations. In the case of a corporation, the corporation has to register the qualified trades in person for in house work only.

The company pays a registration fee every year. It is your responsibility to ensure that all licenses are kept up to date with the City or you will be classified as inactive and unable to submit any documentation under your permit number.

You must register in person as a contractor at:

City of Hamilton
Public Works, Hamilton Water Division
330 Wentworth Street North
Hamilton, ON L8L 5W2

Depending on the category, you will need to bring copies of these documents for our records:

Plumbing Company

The Master Plumber must complete the registration. You can register any Journeyman Plumbers and Apprentice Plumbers under your company. You need to provide copies of these documents:

City of Hamilton Master Plumbing License
City of Hamilton Contractors License
Journeyman Plumbers: Journeyman’s License along with an OWWA or ASSE Testers Certificate
Apprentice Plumbers: Contract of Apprenticeship along with an OWWA or ASSE Testers Certificate
Calibration Certificate for your backflow device test equipment

Fire and Sprinkler Installation Company

The Master Sprinkler and Fire Protection Installer must complete the registration. You can register under your company any:

Journeyman Sprinkler and Fire Protection Installer
Sprinkler and Fire Protection Installer
Apprentice Sprinkler and Fire Protection Installer

You need to provide copies of these documents:

City of Hamilton Master Sprinkler and Fire Protection Installer License
City of Hamilton Contractors License
Journeyman Sprinkler and Fire Protection Installer: Journeyman’s License along with an OWWA or ASSE Tester Certificate
Apprentice Sprinkler and Fire Protection Installer: Contract of Apprenticeship along with an OWWA or ASSE tester Certificate
Calibration certificate for your backflow device test equipment

Professional Engineers

The P. Eng. must complete the registration. You can register any certified Engineering Technologists under your company. You need to provide copies of these documents:

Your P. Eng. Diploma or wallet card along with an OWWA or ASSE testers certificate
CET: your CET certificate along with your OWWA or ASSE testers certificate
Calibration certificate for your backflow device test equipment

Corporations

The corporation must complete the registration. You can register under your corporation any:

Journeyman
Plumbers or Apprentice Plumbers
Journeyman Sprinkler and Fire Protection Installer
Apprentice Sprinkler and Fire Protection Installer

You need to provide copies of these documents:

A letter on company letterhead indicating that the corporation authorizes the individuals to carry out functions for in house use only
Journeyman Plumbers: Journeyman’s plumbing license along with an OWWA or ASSE Testers Certificate
Apprentice Plumbers: Contract of apprenticeship along with an OWWA or ASSE Testers Certificate
Journeyman Sprinkler and Fire Protection Installer: Journeyman’s license along with an OWWA or ASSE Tester Certificate
Apprentice Sprinkler and Fire Protection Installer: Contact of Apprenticeship along with an OWWA or ASSE Tester Certificate
Calibration certificate for your backflow device test equipment

Approved List of Contractors as of June 5, 2025

COMPANY NAME	ADDRESS	PHONE
1844813 ONTARIO LTD.ROTO ROOTER	617 PARKDALE AVE N UNIT 8AHAMILTON ONL8H 5Z1	TEL: (905)570-8788
A-1 PLUMBING & MECHANICAL INC.	440 LAKE AVE., N UNIT 1HAMILTON ONL8E-3C2	TEL: (905)662-7444
AARON ATKINSON	617 PARKDALE AVE N UNIT 8AHAMILTON ONL8H 5Z1	TEL: (905)570-8788FAX: (905)664-4395
ADAMS PLUMBING	94 LYNDEN RDLYNDEN ONL0R-1T0	TEL: (905)627-7739
AINSWORTH	131 BERMONDSEY RDTORONTO ONM4A-1X4	TEL: (416)751-4420
ANTA PLUMBING	364 MUNSTER AVE TORONTO ON M8Z 3C7	TEL: (416)231-3331
ANTHONY BARNABY	3400 14TH AVE UNIT #8MARKHAM	TEL: (647)308-0742
ARCHIE HORN & SON	31 BIGWIN ROAD UNIT 1HAMILTON ONL8W-3R3	TEL: (905)318-5020
AW REANEY	189 CEDARDALE AVESTONEY CREEK ONL8E 1R4	TEL: (289)308-6665
BACKFLOW PRO/TESSCO PLUMBING	21 HOBART CRESBRANTFORD ONN3P 1V5	TEL: (519)750-4244
BATES GROUP INC. O/A BATES PLUMBING	401 VAUGHAN VALLEY BLVDVAUGHAN ONL4H 3B5	TEL: (905)850-7777
BESSELING MECHANICAL INC	79 COVINGTON STREETHAMILTON ONL8E-2Y4	TEL: (905)560-0200FAX: (905)560-0505
BINBROOK PLUMBING LIMITED	RR#1 4045 GUYATT RDBINBROOK ONTARIOLOR 1C0	TEL: (905)549-7252
BIRD MECHANICAL	1201 NICHOLSON RD NEWMARKET ON L3Y 9C3	TEL: (905)954-1020
BLACK & MCDONALD	328 GREEN RDSTONEY CREEK ONL8E-2B2	TEL: (905)560-3100x610FAX: (905)662-5882
BML MULTI TRADES GROUP LTD	32 RYAN PLACE PO BOX 1627 BRANTFORD ON N3T 5V7	TEL: (519)756-4150
BRIAN YOUNG P.ENG.(PROFESSIONAL ENGINEER)	79 ABBOTSFORD TRAILHAMILTON ONTARIOL9B 0A4	TEL: (905)679-3713
BUCCILLI PLUMBING	47 WASHINGTON STNORWICH ONNOJ-1P0	TEL: (519)757-5850
CENTRAL PLUMBING & HEATING	601 Green Mountain Rd EastStoney Creek ONL8J 2Z7	TEL: (905)527-2406
CJ EXPRESS PLUMBING & ELECTRICAL LTD.	240 SHELDON DR CAMBRIDGE ON N1T 1A8	TEL: (519)621-3111
COVE MECHANICAL INC	850 LEGION RD, UNIT #12BURLINGTON ONL7S-1T6	TEL: (905)632-2683
CULLITON INC	473 DOURO STSTRATFORD ONN5A 6W3	TEL: (519)271-8309x8309
DALCRO MECHANICAL CONTRACTING LTD	1402 HAIG BLVDMISSISSAUGA ONL5E 2N1	TEL: (905)274-2657
DDK PLUMBING AND HEATING	22 BROOKHURST CRESCENTWATERDOWN ONL0R-2H3	TEL: (905)690-1483
E.S.FOX LTD	1202 EGERTER RD SPORT ROBINSON ONL0S-1K0	TEL: (905)384-9999
EOS MECHANICAL INC	30 Great Gulf Dr UNIT 27VAUGHAN ONL4K 0K7	TEL: (647)621-6811
EVERDING FIRE PROTECTION LTD	270 MILL ST KITCHENER ONN2M 3R5	TEL: (519)578-6100
Expert Plumbing and Drains INC	3327A MainwayBURLINGTON ONL7M 1A6	TEL: (888)300-1015
FRED'S MAINTENANCE & REPAIR	11 ROSS AVEHAMILTON ONL8W-2N2	TEL: (905)961-8123
FULL FLOW PLUMBING	1290 RENFIELD DRBURLINGTON ON	TEL: (416)317-5069
G.O. TAP PLUS INC	335 Watline AveMISSISSAUGA ONL4Z 1P3	TEL: (416)695-4377FAX: (905)564-7640
GLAD MECHANICAL	901 SLOAN CIRCLE DRCHURCHILL ONTARIOL0L 1K0	TEL: (416)605-1755
GLENN RICHARDSON PLUMBING & HE	2413 INDUSTRIAL STREETBURLINGTON ONL7P-1A6	TEL: (905)335-2945FAX: (905)335-3077
GREG MORO PLUMBING	490 ARVIN AVE STONEY CREEK ON L8E 2M9	TEL: (905)664-2543
GRIFFIN MECHANICAL INC. O/A Secure Water Systems	27 Monarch Road Unit 1BGUELPH ONTARION1K 1N4	TEL: (905)580-1698FAX: (519)822-9260
GTA PLUMBING LTD	6-3995 SLADEVIEW CRESMISSISSAUGA ONL5L-5Y1	TEL: (905)569-7558
HARB PLUMBING	1032 CEDARWOOD PL BURLINGTON ONL7T3J3	TEL: (905)617-6362
HILLS PLUMBING SERVICE	P.O. BOX 69007 1900 KING ST. EHAMILTON ONL8K-6R4	TEL: (905)741-7241
HI-TECH PLUMBING	241 EDGELEY BLVD, CONCORD, ON L4K 3Y6	TEL: (905)761-0700
HOFFER MECHANICAL	460 GRAYS ROADHAMILTON ONL8E-2Z4	TEL: (905)561-6660FAX: (905)578-2755
IAN C ALLEN	211 CARNWITH DR WWHITBY ONL1M-2G3	TEL: (905)242-1016FAX: (905)655-5667
JORDAN KINDT	239 KIRKWOOD DRDUNDAS ONL9H 7A5	TEL: (519)771-2848
JORDAN KINDT BENCHMARK PLUMBING	239 KIRKWOOD DRDUNDAS ONL9H 7A5	TEL: (519)771-2848
JTS MECHANICAL SYSTEMS	5061 WELLINGTON COUNTY RD 32 GUELPH ON N1H 6J4	TEL: (519)635-0022
KEITHS'S PLUMBING & HEATING	647 PARKDALE AVE NHAMILTON ONL8H 5Z1	TEL: (905)544-8118FAX: (905)544-6815
KERR MECHANICAL INC	422 DELAWARE AVEBURLINGTON ONL7R-3B5	TEL: (905)973-5114
L.J. BARTON MECHANICAL INC	1341 OSPREY DRIVE UNIT 4ANCASTER ONL9G-4V5	TEL: (905)304-1976FAX: (905)304-1607
MATTINA MECHANICAL LIMITED	211 LANARK ST UNIT AHAMILTON ONL8E-2Z9	TEL: (905)544-6380
MEADOWBROOK CONSTRUCTION INC	5579 Mcadam RdMississauga ONL4Z 1N4	TEL: (416)819-3800
MICHAEL GRAHAM	473 DOURO STSTRATFORD ONN5A 6W3	TEL: (519)271-1981x8309
MICHAEL GRAHAM	473 DOURO STSTRATFORD ONN5A 6W3	TEL: (519)271-1981x8309
MODERN NIAGARA	8125 HIGHWAY 50VAUGHN ONL4H 4S6	TEL: (416)748-3882x5508
MT DRAIN	604 EDWARD AVE, UNIT #5, RICHMOND HILL, ON L4C 0V4	TEL: (905) 761-5551
NAYLOR GROUP INCORPORATED	455 NORTH SERVICE RDOAKVILLE ONL6H-1A5	TEL: (905)338-8000
NELCO MECHANICAL LTD	1 CORBETT AVEST CATHARINES ONL2N-5M3	TEL: (519)465-7112
NUTECH FIRE PROTECTON / FIRE PLUS	2814 Barton Street EHamilton ONL8E 2J9	TEL: (905)549-0111
ONTARIO FIRE PROTECTION	65 IMPERIAL ST Hamilton ONL8L 4E2	TEL: (289)799-5220
PITTON PLUMBING & HEATING INC	566 RENNIE STHAMILTON ONL8H-3P5	TEL: (905)544-0006
PLUGGED PIPER	4280 HARVESTER RD BURLINGTON ON UNIT 23 BURLINGTON ON	TEL: (905)333-3044
PLUMBERS EDGE	1000 SIMCOE ST NOSHAWA ONL1G8E6	TEL: (905)529-5988
PLUMBWAY INC.	171 GLOVER RDHANNON ONL0R 1P0	TEL: (905)574-3456
PRACTICAL PLUMBING CO LTD	3-1895 BLUE HERON DRLONDON ONN6H 5L9	TEL: (519)471-8392
PRECISION PLUMBING	20 FESTIVAL WAY BINBROOK ONL0R 1C0	TEL: (905)971-4321
PROACTIVE WATER SOLUTIONS INC	2 HOLLAND DR UNIT 9 BOLTON ON L7E 1E1	TEL: (416)249-2837
RAPID PLUMBING INC	94 KENHAR DR UNIT 19 TORONTO ON M9L 1N2	TEL: (416)216-1264
RICK CAMPOVARI	45 Lancing Dr. Unit 3HAMILTON ONL8W 2Z9	TEL: (289)683-6344
ROBERT D. STEWART MECHANICAL	P.O. BOX 57309 110 KING STR WHAMILTON ONL8P-4X2	TEL: (905)529-4805
RUSSELL'S PLUMBING	225 GIBSON AVEHAMILTON ONL8L 6K2	TEL: (905)541-2877
S&J PLUMBING SERVICES IN	3400 14TH AVE UNIT 8MARKHAM ON	TEL: (647)308-0742
STEVENSON SPRINKLER & FIRE PROTECTION	520 JORDAN RD #1, JORDAN STATION, ON L0R 1S0	TEL: (905)562-7575
TOMEL MECHANICAL CONTRACTORS	335 STONE CHURCH ROAD 307ANCASTER ONL9K-1S5	TEL: (905)808-1364
TOWNSEND PLUMBING & HEATING LT	70 HEMPSTEAD DR UNIT BHAMILTON ONL8W-2E7	TEL: (905)574-1100
TRANSPARENT BACKFLOW	473 ALEXMUIR PL WATERLOO ON N2T 1S5	TEL: (519)574-8776
UNDER PRESSURE PLUMBING SERVICES	12901 HWY 27 NOBLETON ON L0G 1N0	TEL: (249)506-6510
VIVE MECHANICAL	200 HACHBORN RDBRANTFORD ONN3S 7W5	TEL: (519)758-3500
WESTERN PLUMBING & HEATING	111 BRIARWOOD CRESCENTHAMILTON ONL9C-4C5	TEL: (905)389-2902FAX: (905)574-1808
XPER-TEK	9 PINELANDS AVE UNIT 9 STONEY CREEK ON L8E 3A4	TEL: (905)664-9000

This list represents companies that have met the requirements and have submitted the proper documentation to register and carry out authorized functions under the Backflow Prevention Program. The City of Hamilton does not endorse or verify quality of workmanship for any contractor, and recommends that all property owners obtain multiple quotes and check references before choosing one of the approved contractors from this list.

Date modified

June 30, 2025