# Re-occurring Leak



## Ken_K (Apr 16, 2020)

My 30 year old system has had 3 or 4 leaks in the main line about 5-6 feet from the meter shut off. There is no back flow preventer or pressure reducing valve and street pressure is routinely 125 psi. The ground is too wet to explore the leak so I don't know if a previous repair has failed or if this is a new problem. I'm in Atlanta so winter frost isn't an issue. 
Each time in the past I've just repaired the problem and it would be fine for 1-4 years. I'm concerned that the high street pressure could be contributing to these failures and I should install a pressure reducer when I fix the leak this time.
Your comments are welcome.


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## corneliani (Apr 2, 2019)

Is this for you irrigation line or water main? What type of pipe? I likewise have 125-ish psi at the street and used 1" Sch40 for the main house line as well as the main irrigation offset to the irrigation manifold... from where I ran CL200 pipe. I have the Hunter valves where I can adjust the pressure if needed, as well as PRS40 heads for exact control at the head. So far no problems (except where I overtightened the valve body to the connectors and managed to crack a couple valves over the offseason!). Dope.

Unfortunately this type of work requires digging... and possibly replacing of lines. You can install a PRV/backflow preventer on your side of the meter to mitigate this high PSI (here's an example of one.. it's approx 12" long and will require it's own box: https://www.grainger.com/product/6A770?gclid=Cj0KCQjw3ZX4BRDmARIsAFYh7ZIYzaobxes5tUclSUdmKImvOyLzKB5LVkYI9dH6Z8rwkPJBQxS0GsEaApXiEALw_wcB&cm_mmc=PPC:+Google+PLA&ef_id=Cj0KCQjw3ZX4BRDmARIsAFYh7ZIYzaobxes5tUclSUdmKImvOyLzKB5LVkYI9dH6Z8rwkPJBQxS0GsEaApXiEALw_wcB:G:s&s_kwcid=AL!2966!3!281698275786!!!g!469890691366!) but it's not cheap. Technically if you have an irrigation system you're required to use a back flow preventer (a simple check valve will suffice). You can keep kicking this can down the road but eventually it'll need addressing, I assume.


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## ken-n-nancy (Jul 25, 2017)

When you've fixed the leak previously, what has been done?

When the leaks have recurred, what form has that been? Have there been new leaks in a replaced section of pipe? Have the prior repairs failed? Has a nearby section of unrepaired pipe failed?


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## Ken_K (Apr 16, 2020)

Thanks for the replies. I dug up the line yesterday and found that one of the couplings from a previous repair had failed. I'm a bit concerned about putting a pressure reducer in and having the throw/range of they heads decrease. I don't know if 60 psi vs 125 psi would substantially change the range and volume of the existing heads. 
The leak involves the main line of the irrigation system. I have a separate meter just for my irrigation system.


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## bernstem (Jan 16, 2018)

If you know the brand of heads you have, you can look up specs on the manufacturer website. For most heads, the max pressure with performance specs is ~65 psi. From 65 to 25 PSI, hunter PGP Ultras, lose ~10% of throw range. As an aside, high pressure leads to misting and poor performance. You should try to design for 45 PSI at the head if you can.


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## Ken_K (Apr 16, 2020)

Update - went out today and cut out the bad fittings and glued in new ones. I turned the main valve back on and about 30 seconds after the main line pressured up, there was water spraying out around the new fitting I just installed. After cussing for a few minutes I cut the just replaced section out and happened to notice a hairline longitudinal crack in the Sched 20 PVC. That was probable what caused my initial leak and I just didn't cut enough of the damaged pipe out. Now I'm wondering what caused that pipe to split. The pipe is deep enough and winters are mild here so I'm doubtful that freezing is an issue.
My sprinkler heads are K2 Pros and it looks like 70 psi is their maximum rating.


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## corneliani (Apr 2, 2019)

That pressure regulating backflow preventor may be a 2 birds (or is it 3?) / one stone solution for you. Just the peace of mind it offers, considering you have 20+ year-old pipe with that high psi that's straining every possible weak point in that pipe. I dunno, it sure would allow me to sleep better if I were in your shoes.


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