4-(1H-Benzimidazol-3-ium-2-yl)benzoate dihydrate

In the title compound, C14H10N2O2·2H2O, the water mol­ecules are involved in hydrogen bonds and interactions. Intermolecular and intramolecular O—H⋯O hydrogen bonds connect the complex into chains along the a axis, whereas N—H⋯O intermolecular hydrogen bonds and C—H⋯O interactions interconnect these layers forming a three-dimensional network.