My dr told me that the hydronephrosis puts me at a high risk for developing kidney infections. how high is this risk and is there anything i can do do reduce tbe risk?

Depends upon cause: Risk of UTI with hyronephrosis(hn) is only significant if hn is associated with bladder reflux or u have past history of utis. Otherwise not. Risk of developing UTI low if cause is congenital blockage. Ur already 30 years-old & obstruction has been present a long time. U may need antibiotics if hn was found after uti.Shower & don't bathe, avoid constipation, cotton & no thong underwear, pee often.