[Adopted 11-13-2013 by Ord. No. 2013.10.09-013 as Ch. 148, Art. I, of the 2013 Code]
A. 
Cross-connections between water supplies and nonpotable sources of contamination are significant threats to health in the water supply industry. This article is designed to maintain the safety and potability of the water in the Community Services Department by establishing rules and procedures to prevent the contamination of public drinking water by the backflow of water from an approved source or other fluids.
B. 
The purpose of this regulation is:
(1) 
To protect the public water supply of the Community Services Department from the possibility of contamination by isolating contaminants which could backflow or backsiphon into the public water system within its customers' internal distribution system(s);
(2) 
To promote the elimination or control of cross-connections, actual or potential, between its customers' in-plant drinking water system(s) and anything that could contaminate or pollute it; and
(3) 
To provide for the maintenance of a cross-connection control program to effectively prevent the contamination or pollution of all drinking water systems.
[Amended 2-12-2020 by Ord. No. 2020.01.08-001]
This article is adopted pursuant to the following:
A. 
New Hampshire Administrative Rules Part Env-Dw 505, Backflow Prevention, or subsequent rules.
B. 
The Dover Utilities Commission rules and regulations approved by the Dover City Council. Under these rules and regulations, the Community Services Department has the primary responsibility for protecting the public water supply from the backflow and cross-contamination of dangerous substances which would endanger the public health or physically damage the public water system.
As used in this article, the following terms shall have the meanings indicated:
AIR GAP
A physical separation sufficient to prevent backflow between the free-flowing discharge end of the potable water system and any other system. Physically defined as a vertical distance equal to twice the diameter of the supply pipe but not less than one inch.
ATMOSPHERIC VACUUM BREAKER
A device which prevents backsiphonage by creating an atmospheric vent when there is either a negative pressure or subatmospheric pressure in a water system.
AUXILIARY WATER SUPPLY
Any water supply on or available to the premises other than the purveyor's approved public potable water supply.
BACKFLOW
The flow of water or other fluids, mixtures or substances into the distribution pipes of a potable water system from any source other than the intended approved source of supply.
BACKFLOW PREVENTER
A device or means designed to prevent backflow or backsiphonage.
BACKPRESSURE
A condition in which the owner's system pressure is greater than the supplier's system pressure.
BACKSIPHONAGE
The flow of water or other fluids, mixtures or substances into the distribution pipes of a potable water system from any source other than its intended source caused by the sudden reduction of pressure in the public water system.
BAROMETRIC LOOP
A fabricated piping arrangement rising at least 35 feet at its topmost point above the highest fixture it supplies. It is utilized in water systems to protect against backsiphonage.
CONTAINMENT
A method of backflow prevention which requires a backflow prevention device at the water service entrance.
CONTAMINANT
A substance that may impair the quality of the water, creating a potential health hazard to the public.
CROSS-CONNECTION
Any actual or potential connection between the public water system and any source of contamination or unapproved water source.
DOUBLE CHECK VALVE ASSEMBLY
An assembly of two independently operating, spring-loaded check valves with tightly closing shut-off valves on each side of the double check valve, plus properly located test cocks for the testing of each check valve.
DUAL CHECK VALVE WITH INTERMEDIATE ATMOSPHERIC VENT
A device having two independently operating, spring-loaded check valves separated by an atmospheric vent chamber.
FIXTURE ISOLATION
A method of backflow prevention in which a backflow preventer, such as a hose bib or an atmospheric vacuum breaker, is located to correct a cross-connection at an in-plant location rather than at a water service entrance. This protects the drinking water in the building.
HOSE BIB VACUUM BREAKER
A device which is connected to a hose bib and which acts as an atmospheric vacuum breaker. Not to be used under constant pressure.
OWNER
Any person who has legal title to, or license to operate or habitat in, a property upon which a cross-connection inspection is to be made or upon which a cross-connection may be present.
PERSON
Any individual, partnership, company, public or private corporation, political subdivision or agency of the state, department, agency or instrumentality of the United States, or any other legal entity.
PRESSURE VACUUM BREAKER
A device containing one or two independently operated, spring-loaded check valves and an independently operated, spring-loaded air inlet valve located on the discharge side of the check valve(s). The device includes tightly closing shutoff valves on each side of the check valve(s) and properly located test cocks for the testing of the assembly.
REDUCED PRESSURE PRINCIPLE BACKFLOW PREVENTER
An assembly consisting of two independently operating, spring-loaded check valves with an automatically operating differential relief valve located between the two check valves, tightly closing shutoff valves on each side of the check valves, plus properly located test cocks for the testing of the check valves and the relief valve.
RESIDENTIAL DUAL CHECK
An assembly of two spring-loaded, independently operating check valves. Generally employed immediately downstream of the water meter to act as a containment device in a single- or two-family residence.
WATER SERVICE ENTRANCE
That point in the owner's water system beyond the sanitary control of the water supplier; generally considered to be the outlet end of the water meter or where the water service first enters the building.
WATER SUPERINTENDENT
The official, or his delegated representative, in charge of the Community Services Department who is invested with the authority and responsibility for the implementation of an effective cross-connection control program and for the enforcement of the provisions of this article.
WATER SUPPLIER
The public water supply system.
The Water Superintendent shall be responsible for the protection of the public potable water distribution system from contamination or pollution due to the backflow or backsiphonage of contaminants or pollution through the water service connection. If, in the judgment of the Water Superintendent, an approved backflow prevention device is required at the City of Dover's water service connection to any customer's premises for the safety of the water system, the Water Superintendent or his designated agent shall give notice, in writing, to said customer to install an approved backflow prevention device at each service connection to his premises. The customer shall, within 90 days, install the approved device or devices at his own expense. Failure, refusal, or inability on the part of the customer to install said device or devices within 90 days shall constitute grounds for discontinuing water service to the premises until such device or devices have been properly installed.
A. 
The Community Services Department will operate an approved cross-connection control chapter, including the keeping of necessary records to fulfill the requirements of the New Hampshire Department of Environmental Services' backflow rules, regulations, and related laws.
B. 
The owner shall allow the City of Dover to inspect his property for possible cross-connections and shall follow the provisions of this article and the rules of the Dover Utilities Commission.
[Amended 2-12-2020 by Ord. No. 2020.01.08-001]
C. 
If the City of Dover requires that the public supply be protected by containment, the owner shall be responsible for the water quality beyond the outlet end of the containment device and should utilize the appropriate device approved for that purpose.
A. 
Community Services Department.
(1) 
On new installations, the City of Dover will provide an on-site evaluation and/or inspection and review of plans in order to determine the type of backflow preventer, if any, that will be required.
(2) 
On new installations, the City of Dover will issue a permit and perform inspection and testing.
(3) 
For premises existing prior to the start of this program, the City of Dover will:
(a) 
Perform an assessment of the function of the premises and determine if it poses a cross-connection risk.
(b) 
If a risk is present, assess the risk as high-hazard or low-hazard.
(c) 
Inform the owner, in writing, of any corrective action deemed necessary, the method of achieving the correction, and the time allowed for the correction to be made. Ordinarily, 30 days will be allowed. However, this time period may be shortened depending upon the degree of hazard involved and the history of the device(s) in question.
(4) 
The City of Dover will not allow any cross-connection to remain unless it is isolated by an approved backflow prevention assembly, commensurate with the degree of hazard, for which a permit has been issued and which will be regularly inspected/tested to ensure satisfactory operation.
(5) 
The City of Dover shall inform the owner, in writing, of any failure to comply and the time allowed for the correction to be made. If upon reinspection the owner has not complied, the City of Dover may allow an additional 15 days for the correction. In the event the owner fails to comply with the necessary correction by the time of the second reinspection, the City of Dover will inform the owner, by certified letter, that the water service to the owner's premises will be terminated within a period not to exceed five days. In the event that the owner informs the City of extenuating circumstances as to why the correction has not been made, a time extension may be granted by the Community Services Director.
(6) 
If the City of Dover determines at any time that a serious threat to the public health exists, the water service shall be terminated immediately.
(7) 
The City of Dover shall begin inspections to determine the nature of existing hazards and corrections to be made, following approval of the program by the New Hampshire Department of Environmental Services (NHDES). Initial focus will be on high-hazard water use.
(8) 
Certified backflow prevention device inspectors must be certified through the New England Water Works Association (NEWWA) Certified Backflow Prevention Device Inspectors/Testers Program.
(9) 
The City of Dover shall also develop installation standards and specifications for each type of backflow preventer to ensure they are installed in a manner in which they have been evaluated and approved and to allow for periodic testing and maintenance.
B. 
Owner.
(1) 
The owner shall be responsible for the elimination, or isolation with the proper installation of an approved backflow preventer commensurate with the degree of hazard, of all cross-connections on his premises.
(2) 
The owner, after having been informed by a letter from the City, shall, at his expense, install, maintain, and inspect or have inspected (as determined by the City of Dover) all backflow preventers on his premises.
(3) 
The owner shall correct any deficiency of a backflow preventer which is revealed by inspection or testing. This shall include the replacement of parts or the replacement of the backflow preventer, if deemed necessary by the Community Services Department.
(4) 
The owner shall inform the Community Services Department of any proposed or modified cross-connections and also existing cross-connections of which the owner is aware but which have not been found by the Community Services Department.
(5) 
The owner shall not install a bypass around any backflow preventer unless there is a backflow preventer of the same type on the bypass. Owners who cannot shut down operations for inspecting of the device(s) must supply additional devices necessary to allow inspecting to take place.
(6) 
The owner shall install backflow preventers in a manner and location approved by the Community Services Department.
(7) 
The owner shall only install approved backflow preventers from a list adopted by the Community Services Department and NHDES.
(8) 
Any owner having a private well or other private water source must:
(a) 
Have a permit if the well or source is cross-connected to the Community Services Department's system. Permission to cross-connect may be denied by the Community Services Department. The owner may be required to install a backflow preventer at the service entrance if a private water source is maintained, even if it is not cross-connected to the Community Services Department's system.
(b) 
In the event the owner installs plumbing to provide drinking water for domestic purposes which is on the City public water system's side of the backflow preventer, such plumbing must have its own backflow preventer installed.
(9) 
The owner shall be responsible for the payment of all fees for permits, annual or semiannual device inspections, retesting in the case that the device fails to operate correctly, and reinspections for noncompliance with the Community Services Department or NHDES requirements.
The Community Services Department recognizes the threat to the public water system arising from cross-connections. All threats will be classified by degree of hazard and will require the installation of approved backflow prevention devices for high and low hazards.
A. 
Low degree of hazard. If backflow were to occur, the resulting effect on the water supply would be a change in its aesthetic qualities. The foreign substance must be nontoxic to humans.
B. 
High degree of hazard.
(1) 
If backflow were to occur, the resulting effect on the water supply could cause illness or death if consumed by humans. The foreign substance may be toxic to humans from either a chemical, bacteriological or radiological standpoint. The effects of the contaminants may result from short- or long-term exposure.
(2) 
Only the following types of backflow prevention devices may be used for the containment of on-site contaminants for high- and low-hazard situations, respectively:
(a) 
High hazard.
[1] 
Air gap (AG).
[2] 
Reduced pressure principal backflow preventer (RPZ).
[3] 
Combination of the above.
(b) 
Low hazard.
[1] 
Air gap (AG).
[2] 
Pressure vacuum breaker (PVB).
[3] 
Double check valve assembly (DCVA).
[4] 
Reduced pressure principal backflow preventer (RPZ).
[5] 
Combination of the above.
The Community Services Department shall not permit a cross-connection within the public water system unless it is considered necessary and cannot be eliminated.
A. 
Cross-connection permits that are required for each backflow prevention device are obtained from the Community Services Department. A fee will be charged for the initial permit and for the renewal of each permit as found in the Fee Schedule.
B. 
Cross-connection permits shall be renewed every five years and are nontransferable. Permits are subject to revocation and become immediately revoked:
[Amended 2-12-2020 by Ord. No. 2020.01.08-001]
(1) 
If the owner should change the type of cross-connection or degree of hazard associated with the service type of device;
(2) 
Upon replacement of the device with a new device; or
(3) 
Upon change of ownership.
C. 
A permit is not required when fixture isolation is achieved with the utilization of a nontestable backflow preventer in the case of residential dual checks.
Any existing backflow preventer shall be allowed by the Community Services Department to continue in service unless the degree of hazard is such as to supersede the effectiveness of the present backflow preventer, or unless an unreasonable risk to the public health results.
A. 
Backflow prevention devices shall be inspected and tested at least semiannually for high hazard devices and annually for low hazard devices.
B. 
Periodic inspections and testing shall be performed by an inspector certified through the NEWWA Backflow Prevention Device Inspectors/Testers Program. The inspections will be done at the owner's expense.
C. 
When performed by an inspector from the Community Services Department, the inspections shall be conducted during the Community Services Department's regular business hours. Exceptions to this, when at the request of the owner, may require additional charges to cover the increased costs to the Community Services Department.
D. 
Any backflow preventer which fails the inspection test during a periodic inspection will be repaired or replaced. When repairs are necessary, upon completion of the repair, the device will be inspected a second time at the owner's expense to ensure correct operation. High-hazard situations will not be allowed to continue unprotected if the backflow preventer fails the inspection and cannot be repaired immediately. In other situations, a compliance date of not more than 30 days after the inspection date will be established. The owner is responsible for spare parts, repair tools, and/or a replacement device. Parallel installation of two devices is an effective means of the owner ensuring that uninterrupted water service is provided during inspections or repair of devices and is strongly recommended when the owner desires such continuity.
E. 
These devices shall be repaired or replaced at the expense of the owner whenever said devices are found to be defective. Tests and repairs shall be recorded on forms approved by the Water Superintendent, and copies shall be distributed to the owner and Water Superintendent within 10 days of the actual test.
F. 
Backflow prevention devices may be inspected more frequently than specified in Subsection A above in cases where there is a history of test failures and the Community Services Department feels that, due to the degree of hazard involved, additional inspections are warranted. Cost of the additional inspections will be borne by the owner.
A. 
Records. The Community Services Department will initiate and maintain the following for a minimum of five years:
(1) 
Master files on customer cross-connection inspections and/or tests.
(2) 
Master files on cross-connection permits.
(3) 
Copies of permits and permit applications.
B. 
Reports. Each year, by April 1, the Community Services Department will submit a summary of inspection results to NHDES that includes the following:
(1) 
The name, certifying organization, and certification number of the certified backflow prevention device inspector who performed the inspection and test on the device;
(2) 
The permit number;
(3) 
The name of the owner and the location of the device;
(4) 
The purpose of the device and its hazard class;
(5) 
The type of device;
(6) 
The date and result of each test; and
(7) 
If the test failed, the subsequent test date and result until the device passes.