A conduit for drip irrigation systems having a wall of a pierceable material characterized by a series of inwardly formed dimples along the length thereof and arranged to be pierced by a piercing member on an off-take or sprinkler, the dimples having a selected wall thickness in relation to the wall of the conduit, the conduit being optionally provided with ribs at the dimples to give further securing means and optionally including a tension wire or member for support.
