Often times during projects where the schedule requirements over-ride everything, including common-sense disconnects occur in the design process.

However in the end all disconnects and variations should be reconciled, otherwise undesirable things may happen.

Also another factor in our economy of today, is everybody wants the cheapest rock bottom price, often times ignoring quality of the final product, the resulting efforts are usually never good... there is cheap and then there is too cheap!

If the differences that exist between the analysis model vs what’s has actually been built are as great as you have stated, then you really have no analysis and therefore do not comply with the intent of the B31.3 code. para. 319.4.1 & 319.4.2.

A field survey should be commissioned, and analysis based on the survey should be done.

Finally any re-design based on the analysis should occur followed by field construction and field inspection of the finished work for compliance to the final design.

Or... sit back and see what happens!!!! The allowable stress for wave displacements will be quite low and if we assume the current system does not meet these low limits a fatigue type failure some time from now may occur. When it occurs it will be a crack and an associated leak.