My house is in Phoenix, Arizona and was built in 1951. The back side of houses on my street back up the back side of houses on the next (parallel) street. There used to be an alley separating the two property sides, but now the houses on my street have picked up this alley space and a cement block wall divides the properties.

The City main drain line runs in the old alley space. I had my house drain line scoped with a camera to determine its health (good) and to identify it's exact location. My house main bisects the back yard and connects with the City Main with a 90* (although I have not seen it personally, it runs perpendicular to the City Main). The house main is cast iron.

My problem - the best location for the new pool is directly in line with the house main. The house main would definitely be affected by any pool construction.

Can the house main use two 45*s and connect to the City main in another location? How to best solve this problem (assuming the pool will be built where the current house main is located)?

Thanks.

You may have to offset around the pool and connect back at the same location. Otherwise, the city may charge you a new tap connection fee, which is usually NOT inexpensive.

You will in the end probably offset your way around the pool. Make sure at least two clean outs to grade are installed in the new work.

Thank you. Is there a rule of thumb for the best way to design the offset/s? In other words, use 45s, but no 90s, etc?

45° elbows are preferable.

You can use 90° elbows, but according to the International plumbing code: 708.3.3: Cleanouts shall be installed at each change of direction GREATER than 45° in the building sewer, building drain and horizontal waist or soil lines. where more than one change of direction occurs in a run of piping only one clean out shall be required for each 40 feet of developed length of the drainage piping.

You still need at least one cleanout outside of the home. You may have one already installed. According to the international plumbing code section 708.3.1: All horizontal drains shall be provided with cleanouts located not more than 100 feet apart.

If the total developed length of your sanitary main is 100 feet or less (including The new offset that you are going to put around your new swimming pool) then you technically do not need a clean out.

You may want to check with your building department to see how close you can be to your neighbors property.

Unless you ALREADY have a lot of pitch you are creating a perpetual maintenance problem by ADDING a significant offset AROUND an object.

You will need a laser device to determine ACCURATELY.

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Thanks again.

About 3' from the foundation the house main drain was identified as 1'10" deep. Just before the City main connection, the depth was 3'5". The nearly straight line run from the two points is about 40ft. If an additional 20ft of pipe is added to accommodate the offset, 60ft of pipe @ 1/4" pitch/ft would require 15" of pitch over than run. That's close. The pitch is there, but the laser seems absolutely necessary. Thanks for the advice.



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to nit pick:

the pitch will be different on the offset itself unless you rerun the entire piping

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Good advice both posts Bernabeu



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The POOL would have to be a certain distance, NOT the sewer, and the pool permit will define WHERE the pool has to go.

I haven't had to do one in years so I cannot tell you, but at that time it was a substantial amount, because they wanted the preinstalled taps to be used, and they can add development fees if they desire.



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