Method and apparatus for rehabilitating an underground water conduit and detecting and drilling a service entrance in the conduit

1. A method for rehabilitating an underground water conduit having at least one service entrance, the method comprising:

plugging the at least one service entrance with a plug having a light emitter which is responsive to the presence of an electromagnetic field;

lining the internal surface of the underground water conduit with a semi-transparent membrane thereby covering the plug;

generating an electromagnetic field with a coil inductor disposed on a drilling head having a drill bit, wherein the coil inductor is adapted to generate an electromagnetic field near the drilling head;

moving the drilling head inside the underground water conduit until the light emitter of the plug is turned on by the electromagnetic field emitted by the coil inductor;

aligning the drill bit with the light emitted by the light emitter through the semi-transparent membrane; and

drilling the plug with the drill bit through the semi-transparent membrane in order to reopen the at least one service entrance.

2. The method of claim 1 , wherein the step of aligning the drill bit utilizes a camera connected to a television monitor aboveground and positioned in front of the drilling head for visually detecting the light emitted by the light emitter through the semi-transparent membrane and for aligning the drill bit with the light emitted by the light emitter.

3. The method of claim 2 , wherein the step of drilling includes remotely operating the drilling head by a technician aboveground looking at the television monitor relaying live images captured by the camera.

4. The method of claim 3 , wherein the step of drilling further includes moving the drilling head rotatably and back and forth along a horizontal axis of the underground water conduit.

5. The method of claim 1 , wherein the light emitter is located in the center of the plug.

6. The method of claim 1 , wherein the coil inductor is wound in an oval shape.

7. A system for rehabilitating an underground water conduit having at least one service entrance, the system comprising:

a plug having a light emitter which is responsive to the presence of an electromagnetic field, wherein the at least one service entrance is plugged with the plug;

a semi-transparent membrane lining the internal surface of the underground water conduit thereby covering the plug;

a drilling head disposed on a body moveable within the underground water conduit, the drill head having a drill bit and a coil inductor concentric with the drill bit, the coil inductor being adapted to generate an electromagnetic field near the drilling head, wherein the light emitter of the plug is adapted to be turned on by the electromagnetic field emitted by the coil inductor to allow visual alignment of the drill bit with the light emitted by the light emitter through the semi-transparent membrane.

8. The system of claim 7 , further comprising a camera connected to a television monitor aboveground and positioned in front of the drilling head for visually detecting the light emitted by the light emitter through the semi-transparent membrane and for aligning the drill bit with the light emitted by the light emitter.

9. The system of claim 8 , wherein the drilling head is remotely operable by a technician aboveground looking at the television monitor relaying live images captured by the camera.

10. The system of claim 9 , wherein the drilling head is rotatable about an axis extending in a horizontal direction of the underground water conduit and movable back and forth along the horizontal axis.

11. The system of claim 7 , wherein the light emitter is located in the center of the plug.

12. The system of claim 7 , wherein the coil inductor is wound in an oval shape.