Systems and methods for sewer monitoring

A sensor unit support structure for supporting a sensor unit in a manhole, the support structure comprising:

• an elongate beam adjustable along its length to span a width of the manhole and support the sensor unit within the manhole;
• first and second mounting brackets associated with respective first and second ends of the beam, each mounting bracket being configured to fasten the beam to an inner surface of the manhole;
• and
• a hanger to couple the sensor unit to the beam, the hanger comprising a first coupling portion at a first end of the hanger configured to couple the hanger to the beam, and a second coupling portion at a second end of the hanger configured to couple the hanger to the sensor unit.

A sensor unit for detecting a selected characteristic in a manhole, the sensor unit comprising:

• one or more sensors;
• a controller communicatively coupled to the sensor;
• first and second casing portions configured to sealingly engage each other and cooperate to form a substantially water tight casing to accommodate the one or more sensors, the controller and a battery for supplying power to the sensor and the controller;
• and
• a battery clip at least partially disposed in one of the first and second casing portions, the battery clip configured to removably couple the battery to the casing,
• wherein the first casing portion is removable from the second casing portion to allow access to an inside of the casing for periodic removal and replacement of the battery.