System and method for detecting cross bores

An apparatus for detecting a cross-bore between a first pipe and a second pipe that are installed underground, the apparatus comprising:

• a support that is movable through the first pipe;
• an electronic circuit assembly mounted to the support to move through the first pipe with the support, the electronic circuit assembly including a controller and a capacitance sensor;
• the capacitance sensor is configured to output to the controller a capacitance value at each location of the capacitance sensor based on an interaction of an electric field generated by the capacitance sensor with an environment of the first pipe at the location of the capacitance sensor;
• wherein the capacitance sensor outputs a first capacitance value when the capacitance sensor is at a location where the environment of the first pipe is underground embedment materials and outputs a second capacitance value when the capacitance sensor is at a location where the environment of the first pipe is a cross-bore intersection with the second pipe, the first capacitance value and the second capacitance value being different capacitance values as (i) the underground embedment materials and (ii) the cross-bore intersection with the second pipe interact differently with the electric field generated by the capacitance sensor;
• and
• the controller is configured to generate an indicator indicative of a presence of a cross-bore when the capacitance sensor outputs the second capacitance value after having outputted the first capacitance value.

A method for detecting a cross-bore between a first pipe and a second pipe that are installed underground, the method comprising:

• moving a capacitance sensor through the first pipe;
• outputting by the capacitance sensor a first capacitance value based on an interaction of an electric field generated by the capacitance sensor with an environment of the first pipe when the capacitance sensor is at a location where the environment of the first pipe is underground embedment materials;
• outputting by the capacitance sensor a second capacitance value based on the interaction of the electric field with the environment of the first pipe when the capacitance sensor is at a location where the environment of the first pipe is a cross-bore intersection with the second pipe, wherein the first capacitance value and the second capacitance value are different as (i) the underground embedment materials and (ii) the cross-bore intersection interact differently with the electric field;
• and
• generating an indicator indicative of a presence of a cross-bore when the capacitance sensor outputs the second capacitance value after the capacitance sensor having outputted the first capacitance value.