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	$227.32 per form
Test Report Fee	$75.25 per test
Backflow Prevention Device Inspection - Regular Hours	$190.69
Backflow Prevention Device Inspection - After Hours	$262.05
Backflow Prevention By-law Contractor Registration Fee	$191.65

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 January 26, 2026

COMPANY NAME	ADDRESS	PHONE
1844813 ONTARIO LTD.ROTO ROOTER	617 PARKDALE AVE N UNIT 8A HAMILTON, ON L8H 5Z1	905-570-8788
A-1 PLUMBING & MECHANICAL INC.	440 LAKE AVE., N UNIT 1HAMILTON, ON L8E 3C2	905-662-7444
ADAMS PLUMBING	94 LYNDEN RD, LYNDEN, ON L0R 1T0	905-627-7739
AINSWORTH	131 BERMONDSEY RD, TORONTO, ON M4A 1X4	416-751-4420
ANTA PLUMBING	364 MUNSTER AVE, TORONTO ON M8Z 3C7	416-231-3331
ANTHONY BARNABY	3400 14TH AVE UNIT #8 MARKHAM, ON	647-308-0742
ARCHIE HORN & SON	31 BIGWIN ROAD UNIT 1 HAMILTON, ON L8W 3R3	905-318-5020
AW REANEY	189 CEDARDALE AVE STONEY CREEK, ON L8E 1R4	289-308-6665
BACKFLOW PRO/TESSCO PLUMBING	21 HOBART CRES BRANTFORD, ON N3P 1V5	519-750-4244
BATES GROUP INC. O/A BATES PLUMBING	401 VAUGHAN VALLEY BLVD VAUGHAN, ON L4H 3B5	905-850-7777
BESSELING MECHANICAL INC	79 COVINGTON STREET HAMILTON, ON L8E 2Y4	905-560-0200 FAX: 905-560-0505
BIRD MECHANICAL	1201 NICHOLSON RD NEW MARKET, ON L3Y 9C3	905-954-1020
BLACK & MCDONALD	328 GREEN RD STONEY CREEK, ON L8E-2B2	905-560-3100x610 FAX: 905-662-5882
BML MULTI TRADES GROUP LTD	32 RYAN PLACE PO BOX 1627 BRANTFORD, ON N3T 5V7	519-756-4150
BUCCILLI PLUMBING	47 WASHINGTON ST NORWICH, ON NOJ 1P0	519-757-5850
CENTRAL PLUMBING & HEATING	601 Green Mountain Rd East Stoney Creek. ON L8J 2Z7	905-527-2406
CJ EXPRESS PLUMBING & ELECTRICAL LTD.	240 SHELDON DR CAMBRIDGE, ON N1T 1A8	519-621-3111
COVE MECHANICAL INC	850 LEGION RD, UNIT #12 BURLINGTON, ON L7S-1T6	905-632-2683
CULLITON INC	473 DOURO ST STRATFORD,ON N5A 6W3	519-271-1981
DALCRO MECHANICAL CONTRACTING LTD	1402 HAIG BLVD MISSISSAUGA, ON L5E 2N1	905-274-2657
DDK PLUMBING AND HEATING	22 BROOKHURST CRESCENT, WATERDOWN, ON L0R-2H3	905-690-1483
E.S.FOX LTD	1202 EGERTER RD SPORT ROBINSON, ON L0S 1K0	905-384-9999
EOS MECHANICAL INC	30 Great Gulf Dr UNIT 27 VAUGHAN,ON L4K 0K7	647-621-6811
EVERDING FIRE PROTECTION LTD	270 MILL ST KITCHENER, ON N2M 3R5	519-578-6100
Expert Plumbing and Drains INC	3327A Mainway BURLINGTON, ON L7M 1A6	888-300-1015
FLOTECH CANADA INC	11623 15 SIDE RD GEORGETOWN ON L7G 4S6	416-200-7116
FRED'S MAINTENANCE & REPAIR	11 ROSS AVE HAMILTON, ON L8W 2N2	905-961-8123
FULL FLOW PLUMBING	1290 RENFIELD DR BURLINGTON, ON	416-317-5069
G.O. TAP PLUS INC	335 Watline Ave MISSISSAUGA, ON L4Z 1P3	416-695-4377 FAX: 905-564-7640
GLAD MECHANICAL	901 SLOAN CIRCLE DR ,CHURCHILL, ON L0L 1K0	416-605-1755
GLENN RICHARDSON PLUMBING & HE	2413 INDUSTRIAL STREET BURLINGTON, ON L7P 1A6	905-335-2945 FAX: 905-335-3077
GREG MORO PLUMBING	490 ARVIN AVE STONEY CREEK, ON L8E 2M9	905-664-2543
GRIFFIN MECHANICAL INC. O/A Secure Water Systems	27 Monarch Road Unit 1B GUELPH, ON N1K 1N4	905-580-1698 FAX: 519-822-9260
GTA PLUMBING LTD	6-3995 SLADEVIEW CRES MISSISSAUGA, ON L5L 5Y1	905-569-7558
HARB PLUMBING	1032 CEDARWOOD PL BURLINGTON, ON L7T3J3	905-617-6362
HILLS PLUMBING SERVICE	P.O. BOX 69007 1900 KING ST. E HAMILTON, ON L8K 6R4	905-741-7241
HI-TECH PLUMBING	241 EDGELEY BLVD, CONCORD, ON L4K 3Y6	905-761-0700
HOFFER MECHANICAL	460 GRAYS ROAD HAMILTON, ON L8E 2Z4	905-561-6660 FAX: 905-578-2755
IAN C ALLEN	211 CARNWITH DR W WHITBY, ON L1M 2G3	905-242-1016 FAX: 905-655-5667
JORDAN KINDT	239 KIRKWOOD DR DUNDAS, ON L9H 7A5	519-771-2848
JORDAN KINDT BENCHMARK PLUMBING	239 KIRKWOOD DR DUNDAS, ON L9H 7A5	519-771-2848
JTS MECHANICAL SYSTEMS	5061 WELLINGTON COUNTY RD 32, GUELPH, ON N1H 6J4	519-635-0022
KEITHS'S PLUMBING & HEATING	647 PARKDALE AVE N HAMILTON, ON L8H 5Z1	905-544-8118 FAX: 905-544-6815
KERR MECHANICAL INC	422 DELAWARE AVE BURLINGTON, ON L7R 3B5	905-973-5114
L.J. BARTON MECHANICAL INC	1341 OSPREY DRIVE UNIT 4 ANCASTER, ON L9G 4V5	905-304-1976 FAX: 905-304-1607
MATTINA MECHANICAL LIMITED	211 LANARK ST UNIT A HAMILTON, ON L8E 2Z9	905-544-6380
MEADOWBROOK CONSTRUCTION INC	5579 Mcadam Rd Mississauga, ON L4Z 1N4	416-819-3800
MICHAEL GRAHAM	473 DOURO ST STRATFORD, ON N5A 6W3	519-271-1981x8309
MICHAEL GRAHAM	473 DOURO ST STRATFORD, ON N5A 6W3	519-271-1981x8309
MODERN NIAGARA	8125 HIGHWAY 50VAUGHN, ON L4H 4S6	416-748-3882x5508
MT DRAIN	604 EDWARD AVE, UNIT #5, RICHMOND HILL, ON L4C 0V4	905- 761-5551
NAYLOR GROUP INCORPORATED	455 NORTH SERVICE RD OAKVILLE, ON L6H 1A5	905-338-8000
NELCO MECHANICAL LTD	1 CORBETT AVEST CATHARINES, ON L2N 5M3	519-465-7112
NUTECH FIRE PROTECTON / FIRE PLUS	2814 Barton Street E HAMILTON, ON L8E 2J9	905-549-0111
ONTARIO FIRE PROTECTION	65 IMPERIAL ST, HAMILTON, ON L8L 4E2	289-799-5220
PITTON PLUMBING & HEATING INC	566 RENNIE ST HAMILTON, ON L8H 3P5	905-544-0006
PLUGGED PIPER	4280 HARVESTER RD, UNIT 23 BURLINGTON, ON	905-333-3044
PLUMBERS EDGE	1000 SIMCOE ST N, OSHAWA, ON L1G8E6	905-529-5988
PLUMBWAY INC.	171 GLOVER RD HANNON,ON L0R 1P0	905-574-3456
PRACTICAL PLUMBING CO LTD	3-1895 BLUE HERON DR, LONDON, ON N6H 5L9	519-471-8392
PRECISION PLUMBING	20 FESTIVAL WAY BINBROOK, ON L0R 1C0	905-971-4321
PROACTIVE WATER SOLUTIONS INC	2 HOLLAND DR UNIT 9 BOLTON, ON L7E 1E1	416-249-2837
RAPID PLUMBING INC	94 KENHAR DR UNIT 19 TORONTO, ON M9L 1N2	416-216-1264
RICK CAMPOVARI	45 Lancing Dr. Unit 3 HAMILTON,ON L8W 2Z9	289-683-6344
ROBERT D. STEWART MECHANICAL	P.O. BOX 57309 110 KING STR WHAMILTON, ON L8P 4X2	905-529-4805
RUSSELL'S PLUMBING	225 GIBSON AVE HAMILTON, ON L8L 6K2	905-541-2877
S&J PLUMBING SERVICES IN	3400 14TH AVE UNIT 8 MARKHAM, ON	647-308-0742
SELECT FIRE PROTECTION	2459 INDUSTRIAL ST BURLINGTON,ON L7P 1A6	289-635-2150
STEVENSON SPRINKLER & FIRE PROTECTION	520 JORDAN RD #1, JORDAN STATION, ON L0R 1S0	905-562-7575
TOMEL MECHANICAL CONTRACTORS	335 STONE CHURCH ROAD 307, ANCASTER, ON L9K 1S5	905-808-1364
TOWNSEND PLUMBING & HEATING LT	70 HEMPSTEAD DR UNIT BHAMILTON, ON L8W 2E7	905-574-1100
TRADE-MARK INDUSTRIAL INC	250 ROYAL OAK RD CAMBRIDGE, ON N3E 0A4	519-650-7444
TRANSPARENT BACKFLOW	473 ALEXMUIR PL WATERLOO, ON N2T 1S5	519-574-8776
UNDER PRESSURE PLUMBING SERVICES	12901 HWY 27 NOBLETON, ON L0G 1N0	249-506-6510
VIVE MECHANICAL	200 HACHBORN RD BRANTFORD, ON N3S 7W5	519-758-3500
WATER BRIDGE ENVIRONMENTAL	79 ABBOTSFORD TRAIL, HAMILTON, ON L9B 0A4	905-679-3713
WESTERN PLUMBING & HEATING	111 BRIARWOOD CRESCENT HAMILTON, ON L9C 4C5	905-389-2902 FAX: 905-574-1808
XPER-TEK	9 PINELANDS AVE UNIT 9 STONEY CREEK, ON L8E 3A4	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

January 26, 2026