Have a flow test in a semi-rural area that has static pressures of over 130 psi but a residual pressure of 60 psi at just 500 gpm.
A flow test from nearly a decade ago shows worse results - with a static of around 120 and a residual of 20 psi at just 600 gpm.
My initial concern with the older flow test was a partially-closed valve or obstruction in the line.
With the newer test the residual pressure seems more reasonable, but other than something being wrong with the system is there a reason that would justify a residual pressure less than half the static at only 500 gpm of flow? Perhaps a system fed with small pumps and no tower? What are your thoughts?
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