Water supply pipe joint fixing

[Charlie080]

We recently had a leak in the water supple pipe between an external water meter and the where the pipe enters the building. The leak occurred where the pipe ran underneath the entrance walkway (about 600-700mm deep). Once we excavated and found the leak, we found it was at a joint in the pipe which had a screw fitting (photo attached).
I was wondering why this had happened as the whole block is only 10 months old? Is this type of fitting appropriate below ground? should there be protective ducting around the supply pipe?
Any advice would be appreciated.

 

[ShaunCorbs]

Could of been installed correctly but it's approved for underground use

 

[Charlie080]

Do you think it just wasn't tightened enough when installed? Or is this a common problem in general ?

Thanks

 

[ShaunCorbs]

Could be installer error or pipe too short etc / not all the way in

 

[snowhead]

Or too much pressure put on the joint when the ground was compacted above it.

 

[justlead1]

These fitting are used a lot for MDPE pipes. However inserts should have been used with these fittings. Inserts push in the pipe end before fitting is fitted, they are designed to prevent the pipe collapsing and joint leaking and or pulling of pipe.

 

[Janice H. Salazar]

Did you ever consult this with any plumber?

 

[Stigster]

Was the end of the pipe inside the fitting in good condition with no deep scratches or other damage? I have seen them leak where the pipe has been scratched as it was pulled through/under objects. The scratch being under the O-ring and produced a leak.