H2O + L-histidinol phosphate = L-histidinol + phosphate Amino-acid biosynthesis; L-histidine biosynthesis; L-histidine from 5-phospho-alpha-D-ribose 1-diphosphate: step 8/9. Present with 4280 molecules/cell in log phase SD medium. Belongs to the PHP hydrolase family. HisK subfamily.