HydroCorp conducts over 25,000 cross-connection control inspections on an annual basis. These inspections/surveys consist of containment as well as isolation surveys of the entire potable water system downstream of the water meter.

1. Top 10
Cross-Connection
Hazards
Threatening Your Drinking Water

2. • We conduct over 25,000 Cross-Connection Control
Inspections/Site Surveys annually.
• Many Surveys are downstream of water meter, and
include potable plumbing of entire building.
• Commercial, Industrial and Government Facilities as
well as Residential Homes.
Here’s a list of our 10 most common findings
DATA

3. Regulations in some states may require Backflow Protection at the
Service Supply. Pictured above is a service connection without
backflow protection on a bypass line (closed valve only).
Containment or
Service Protection

4. Recommended Action
Install and test an equivalent type of required assembly
(ASSE 1013) on the bypass at the service connection.

5. Toilet water closets (tanks) with unapproved or
incorrectly installed backflow prevention #10
CLICK HERE for Educational Video
On toilet fill valves – ASSE #1002

6. #10 - Recommended Action
Install an ASSE #1002 type fill valve, available at hardware and
home supply stores. Many older style fill valves are not
approved for backflow protection.

7. Improper plumbing installations related to
backflow hazards
# 9
POTABLE WATER

8. #9 - Recommended Action
The ASSE #1001 Atmospheric Vacuum Breaker is not
code compliant for this application. The vacuum
breaker has elevated piping downstream of the unit,
and may also be connected to a pressurized piping
system, resulting in backpressure causing vacuum
breaker leaking and malfunction.
Install an ASSE #1013 backflow preventer assembly
in the supply to the Process Water system. Properly
label piping downstream of assembly as “Non-
Potable Water”.

9. # 8
Industrial use valved hose drops with incorrect
type of backflow prevention

10. #8 - Recommended Action
• Install an ASSE #1020, #1013 or #1056 backflow preventer
assembly (selection dependent upon type of backflow) and
ensure testing and recordkeeping of assembly on minimum
annual basis. Properly label piping downstream of assembly
as “Non-Potable Water”.
• The circled device is an ASSE #1012 type backflow
preventer. It is only rated and appropriate for low hazard
type protection of the potable water supply. The piping
downstream of the device serves a frequently used acid
battery maintenance filling station, and represents a high
hazard cross connection.

11. Residential boilers with improper OR missing
backflow prevention
# 7

12. #7 - Recommended Action
• Install an ASSE #1012 type backflow preventer and
properly plumb the relief port with an approved air
gap to drain.
• This water supply to a residential boiler has an ASSE
#1012 type backflow preventer. While it is the
correct type of backflow preventer for this
application, it has been modified with a shut-off
spigot valve on the relief port. The relief port is
designed to drain water and may indicate unit failure
or potential backflow.

13. Soda fountain carbonators with missing or
improper backflow prevention
# 6

14. #6 - Recommended Action
• Install an ASSE #1022 device and ensure relief port is
properly air gapped to drain.
• Soda Fountain Carbonator Machines are found in
nearly all fast food chains, taverns, restaurants and
sporting venues. Each carbonator uses a high pressure
boosting pump in order to mix the water supply with
the CO2 prior to the flavor added at the dispensing
nozzle. Carbonators may come from the manufacturer
with an ASSE #1022 type backflow preventer. While this
is the correct device, the relief port (intended to relieve
backpressure) is plugged to stop a perceived “leak”.

15. Chemical soap dispenser mixers incorrectly
installed to utility sinks
# 5

16. #5 - Recommended Action
• Install an open flow water bleeding “tee” after the faucet
backflow preventer and use code compliant hose material
to supply dispenser. *Consult with dispenser manufacturer
to ensure proper GPM/Flow needed for mixing function
when a water bleeding tee is added. Some dispenser
companies provide their own bleeding tee with each
dispenser unit.
• Chemical soap mixers that depend on water supply
connection have a variety of design and functions. Often the
dispenser is supplied in a manner that renders the existing
vacuum breaker backflow preventer inoperable. This photo
depicts an existing ASSE #1011 vacuum breaker on the
fixture. The piping and dispenser control valve downstream
of the backflow preventer represents an installation that is
not code compliant.

17. #5 - Example A wasting tee should be installed on the
faucet end. This tee allows water to flow
from the faucet up to the soap dispenser,
and as the water supply is turned on, water
will also continuously flow out of the
bottom of the tee into the sink.
There is a flow restrictor at the tee
discharge into the sink, which allows
positive flow to be maintained up to the
soap dispenser. When the user has
completed their operation, the water supply
valves on the faucet must be turned off,
otherwise water will continue to drain from
the bottom of the tee.
The wasting tee essentially forces a user to
shut off the water supply when bucket
filling is complete, and as a result water
drains from the hose between the faucet
and the dispenser. This prevents
continuous pressure and backpressure on
the atmospheric vacuum breaker on the
faucet.

18. Incorrectly installed backflow preventer for lawn irrigation system
(incorrect orientation, unapproved installation, etc.)
# 4

19. #4 - Recommended Action
• Install and test (at installation and at intervals required
by AHJ) an ASSE #1020 Pressure Vacuum Breaker
Assembly. (ASSE #1013 may also be used if required by
code or the AHJ)
• This ASSE #1001 Atmospheric Vacuum Breaker in a
supply to a lawn irrigation system was incorrectly
installed sideways (green label should face up). The
black wire feeds a solenoid zone valve downstream of
the backflow preventer. This type of device is not
approved to have control valves installed downstream,
and must be installed in an upright position.

20. Chemically treated boilers with
improper/missing backflow protection
# 3

21. #3 - Recommended Action
• Install an ASSE #1013 backflow preventer assembly
and ensure testing/recordkeeping of assembly on a
minimum annual basis or as required by AHJ.
Properly label piping downstream of assembly as
“Non-Potable Water”.
• The circled piping is where a backflow preventer
should be installed to supply water to this
chemically treated boiler system.

22. Missing or improper air gaps on water cooled
machines, process tanks and/or water softener
discharges
# 2

23. #2 - Recommended Action
• This water supply to a caustic tank mixture does
not have an approved air gap.
• Install an approved air gap separation of a
minimum of 1 inch, or an air gap size equivalent to
twice the supply piping diameter above the flood
level rim. In this example, the supply piping
diameter was 2 inches, thus a 4 inch air gap above
the flood level rim is required. (ASME A112.1.2)

24. Missing backflow protection on Hose Bibb
# 1

25. #1 - Recommended Action
• Install an ASSE #1011, #1013, #1020 or #1056 backflow
preventer assembly (selection dependent upon type of
backflow and valve location).
• The most common cross connection we find is the hose
bibb connection with no backflow preventer. In many
cases, we find hose connections arranged in ways that
render the existing backflow preventer inoperable or
prone to failing due to continuous pressure or
backpressure potential. In this photo, multiple
unprotected connections to one fixture pose a hazard
to the drinking water supply.

26. TOP 10 Common
Cross-Connection Hazards
1. Missing Hose Bibb Vacuum Breaker
2. Improper Air Gap
3. Improper protection on chemically treated boilers
4. Incorrectly installed backflow preventers
5. Chemical dispensing systems
6. Soda fountain carbonator dispensing systems
7. Residential boilers with improper backflow protection
8. Hose reels
9. Improper plumbing installation, incorrect application
10. Toilet fill valves

27. Evaluating Backflow Protection
- Is the application a high or low hazard?
- Is the device subject to backsiphonage, backpressure, or both conditions?
- Is the device subject to continuous or intermittent pressures?
- Are there any control valves located downstream of the device?
- Is the application subject to freezing?
- Is the device located near electrical equipment?
- Is there acceptable room for maintenance and testing?
- What will the pressure loss be through the device?
- Does the application require continuous service?

28. • Industrial / Manufacturing
• Schools & Colleges
• Restaurant / Fast Food Facilities
Top Facilities Requiring
Corrective Action

29. On average, nearly ½ of the
facilities that we initially
survey/inspect have some type
of cross-connection hazard
that needs corrective action.
50%

30. For More Information:
HydroCorp – Corporate Office
5700 Crooks Rd., Ste. 100
Troy, MI 48098
hydrocorpinc.com
info@hydrocorpinc.com
800.690.6651
We help over 250 Public Water
Systems as well as industrial,
healthcare and government
facilities with comprehensive
Cross-Connection Control
Programs and Site Surveys.
Backflow Prevention, Cross
Connection Control Rules and
Regulations vary by state. Check
with your local Authority Having
Jurisdiction (AHJ) and Plumbing
Code for applicable regulations
in your area.
Click here for more information: