Non-disruptive underground pipe replacement process
View Patent ↗A method of installing a new underground pipe adjacent an existing underground pipe begins with drilling a series of substantially vertical boreholes downwardly from the ground surface so as to expose a portion of the existing pipe. Then, a pilot stem is directionally bored in a first direction adjacent the existing pipe and intersecting the bottoms of the vertical boreholes. Next, a reamer head is pulled in an opposite direction to enlarge the pilot hole, while pulling the new pipe through the enlarged hole behind the reamer head. The new pipe extends substantially parallel and adjacent the existing pipe. When the existing pipe is a water main, water service through the existing pipe is maintained during these drilling steps, until the new pipe is installed and connected for water service. The existing pipe is retained and can be repurposed for other uses.
1 . A method of installing a new underground pipe adjacent an existing underground pipe, comprising:
forming a series of substantially vertical bore holes downwardly from ground surface whereby each vertical bore hole visibly exposes the existing underground pipe while maintaining service through the existing pipe;
directionally boring a hole to pass through each of the boreholes adjacent the existing pipe;
and pulling a new pipe through the hole while maintaining service through the existing pipe.
2 . The method of claim 1 wherein the hole is drilled with a boring stem, and the boring stem is observed through the bore holes.
3 . The method of claim 1 wherein water connected to customers via the existing pipe is shut off only after the new pipe is laid.
4 . The method of claim 1 wherein the existing pipe is re-purposed for use by other utilities.
5 . The method of claim 1 further comprising reaming the hole to a larger diameter ahead of the new pipe.
6 . The method of claim 5 further comprising supplying liquid during the reaming to create a slurry which is expelled out of the bore holes.
7 . The method of claim 1 wherein the existing and new pipes are at substantially same elevations.
8 . The method of claim 1 wherein the new pipe resides within a few inches of the existing pipe.
9 . The method of claim 1 further comprising maintaining service to customers connected to the existing pipe until the new pipe is installed.
10 . The method of claim 1 wherein the new pipe runs parallel to the existing pipe.
11 . The method of claim 1 wherein the new pipe is spaced laterally from the existing pipe.
12 . The method of claim 1 wherein the new pipe is spaced above the existing pipe.
13 . The method of claim 1 wherein a supply of water to the existing pipe is not shut off until the new pipe is installed.
14 . The method of claim 1 wherein the existing pipe remains functional until the new pipe is installed.
15 . A replacement process for an existing underground pipe, comprising:
drilling bore holes downwardly from a ground surface to visibly expose the existing pipe, and without cutting into the existing pipe; then
boring a pipe hole substantially parallel to the existing pipe and extending through the bore holes; then
pulling a new pipe through the pipe hole; and
maintaining service of the existing pipe while the new pipe is pulled into the pipe hole.
16 . The process of claim 15 wherein the pipe hole is formed by a pilot stem pulled in a first direction and a reaming head pulled in an opposite second direction.
17 . The process of claim 15 wherein the existing pipe is retained for re-purposed use.
18 . The process of claim 15 further comprising providing service to the new pipe before service of the existing pipe is discontinued.