As many have pointed out about the gas and the point of attachment for the bonding jumper I will address the bonding of the hot to the cold water at the water heater.
If one is under the impression that the hot and cold pipes constitute two separate piping systems then a bond from one system to the other system at the water heater would be a code violation.
Read carefully 250.104(A)(1).
Which one is being bonded to the other? It wouldn?t much matter as whichever is being bonded this bond conductor must be bonded to one of the following;
- service equipment enclosure
- the grounded conductor at the service
- the grounding electrode conductor where of sufficient size
- one or more grounding electrodes used
If the idea is that the cold is one system then that system must have a bonding jumper installed from an assessable point back to one of the items outlined above.
If the idea is that the hot is one system then that system must have a bonding jumper installed from an assessable point back to one of the items outlined above.
Neither the hot nor the cold water pipe at the water heater would fulfill one of the requirements outlined above unless the water heater is installed within 5 feet of where the cold water enters the building. So unless the heater is at the point of entry then the bonding across the water heater is not compliant and would serve no purpose at all as only the first five feet of water pipe that enters the building can be used to attach a bonding jumper to.