Abstract: A horizontal directional drilling system is provided. The system includes a first tank for containing fluid therein, a second tank for containing fluid therein, a manifold comprising at least one inlet port and at least one outlet port, a feed line extending from the manifold, and a valve system configured to control fluid flow to and from the manifold. The valve system is configured to provide selective flow communication to the manifold from one of the first tank or the second tank through the at least one inlet port, and is configured to provide selective flow communication from the manifold to one of the first tank, the second tank, or the feed line through the at least one outlet port.