The details of local codes vary from place to place, but we have summarized some typical code issues in this section. For more detailed information, contact your local permit office. In large cities, you will usually find knowledgeable people on the staff if you get the right person. In smaller cities, many counties, and MUDs you will sometimes find that they are not really familiar with what is required, either because there is no defined rule, or the people you find don't know what the rules are. In any event, you should always design and operate your system to the strictest codes which apply to your area.

• Why do I need a permit?
• What happens if I don't get a permit?
• How much does a permit cost?
• Where do I get the permit?
• What does "pulling" a permit mean?
• What inspections are needed?
• How do I schedule the inspection?
• What restrictions affect backflow preventer installation?

We sincerely hope you will find helpful information in these pages. Be sure to check our indexed Frequently Asked Questions (FAQ) and Answers pages first to see if your questions have already been answered. If you can't find the answer you are looking for, submit your question to and we will consider including your question in our FAQs pages. Unfortunately, due to the volume of questions we receive, we can't answer them all personally, but we'll let you know if we decide to include your question and answer on our site.

 

Why do I need a permit?

The permit is required to enable the water utility to enforce safety restrictions regarding hook-up to the water supply.

 

What happens if I don't get a permit?

You may be caught and fined, and your water can be shut off if you refuse to obtain a permit. When your house is sold and the buyer's inspection determines that you have an unpermitted system it may delay closing, detract from the value of the property instead of enhance it, and you may be required to dig up portions of the system and schedule a formal inspection.

 

How much does the permit cost?

It's not expensive. It usually runs around $25 to $35.

 

Where do I get the permit?

Look up the number for the building permit office for your city or county. You are looking for a plumbing permit for a homeowner-installed irrigation system. If they seem uncomfortable with your request, assure them you don't intend to cut any corners, and will meet all applicable codes. They should have some copies of a summary of applicable codes. For more information you can also contact the board of irrigators, or the board of plumbers if no board of irrigators exists for your state.

 

What does "pulling" a permit mean?

It means "getting" a permit, that's all.

 

What inspections are needed?

The backflow preventer installation is the main item (and perhaps the only item) they are interested in. It must be installed with all necessary valves and valve boxes between the backflow preventer and the water supply. The trench connecting the backflow preventer and the water supply must be open to allow measurements of the amount of cover over the pipe. You may be required to have the backflow preventer tested after installation to verify it is functioning properly before a final inspection can be scheduled. If so, contact a certified backflow prevention testing service to perform this test.

 

How do I schedule the inspection?

Call the permit office to schedule a final inspection. You normally don't need to be there when they inspect unless you want to understand what to fix in case you fail the inspection.

 

What restrictions affect backflow preventer installation?

There are many restrictions that control the installation of backflow preventers. Only SOME of them are listed below. The restrictions below usually influence the type of backflow preventer that you select. Once you have selected a type of backflow preventer, you should contact your local permit office for a detailed list of installation restrictions.

AVB (Atmospheric Vacuum Breaker) -lowest grade of backflow prevention, some restrictions which apply to their installation include:

- May not be under continual pressure- must be installed downstream from a control valve

- Must be installed at least 12" in elevation above the highest sprinkler

- May not be used under high hazard situations, such as fertilizer injection systems

PVB (Pressure Vacuum Breaker) -higher grade of protection and typically must be installed with the following restrictions:

- Must be installed at least 12" in elevation above the highest sprinkler

- May not be used under high hazard situations, such as fertilizer injection systems

DCA (Double Check Assembly) -the most common type of backflow prevention which typically must be installed with the following restrictions:

- Usually the only form of backflow prevention allowed to be installed underground

- May not be used under high hazard situations, such as fertilizer injection systems

- Do not confuse the DCA with a double check valve (or dual check valve) which is usually much cheaper and NOT suitable for backflow prevention!

RPZ (Reduced Pressure Zone) -highest grade of backflow prevention, typically must be installed with the following restrictions:

- Must be installed 12 inches above ground

- May be used under high hazard situations, such as fertilizer injection systems

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