An apparatus and method for facilitating eversion of a flexible liner down a borehole when an artesian head condition is producing a rate of water flow out of the top of the borehole. A bypass pipe channels artesian flow, moving upward in the borehole and/or well casing, past an everting flexible liner to a wellhead fixture. Artesian flow arriving at the wellhead fixture is pumped away to ameliorate resistance to liner eversion otherwise presented by the water flow. A heavy mud may be disposed inside the everting liner further to promote its downward eversion past the artesian flow.