Well monitoring system

A method for monitoring water resources in a well bore having an air column extending from a wellhead to a water surface level and a water column extending from the water surface level to an extraction inlet, comprising:

• transmitting from the wellhead and into the bore at least a single sound pulse and receiving a return signal representing a reflection of the single sound pulse from the water surface level, and
• determining a round trip time between transmitting the single sound pulse and receiving the corresponding return signal,
• each single sound pulse having a duration in the range of 20 milliseconds to 50 milliseconds, and
• from the round trip time,
• determining an air column length from the wellhead to the water surface level and a water column length from the water surface level to the extraction inlet, and
• from a cross sectional area of the bore,
• determining a water resource value representing a volume of water contained between the water surface level and the extraction inlet.

A monitoring system for monitoring a resource in a bore having an air column extending to a resource surface level and a resource column extending from the surface level to an extraction inlet, comprising:

• a sensor unit including,
• a sensor mounted within the bore and including a transmitting unit for transmitting at least a single sound pulse into the bore and a receiving unit for receiving a return signal representing the single sound pulse reflected from the resource surface level, and
• a sensor control for controlling the transmission of the single sound pulse and determining a round trip time between transmitting the single sound pulse and receiving the corresponding return signal,
• each single sound pulse having a duration in the range of 20 milliseconds to 50 milliseconds,
• a base unit for determining, from the round trip time,
• an air column length from the sensor to the resource surface level and a resource column length from the resource surface level to the extraction inlet, and
• from a cross sectional area of the bore,
• a resource value representing a volume of the resource contained between the surface level and the extraction inlet.

A method for monitoring resources in a bore having an air column extending to a resource surface level and a resource column extending from the resource surface level to an extraction inlet, comprising:

• transmitting at least a single sound pulse into the bore and receiving a return signal representing a reflection of the single sound pulse from the resource surface level, and
• determining a round trip time between transmitting the single sound pulse and receiving the corresponding return signal,
• each single sound pulse having a duration in the range of 20 milliseconds to 50 milliseconds, and
• from the round trip time,
• determining an air column length to the resource surface level and a resource column length from the resource surface level to the extraction inlet, and
• from a cross sectional area of the bore,
• determining a resource value representing a volume of resource contained between the resource surface level and the extraction inlet.