I suspect that's VC 22651(b) ...
22651. A peace officer, as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2 of the Penal Code, or a regularly employed and salaried employee, who is engaged in directing traffic or enforcing parking laws and regulations, of a city, county, or jurisdiction of a state agency in which a vehicle is located, may remove a vehicle located within the territorial limits in which the officer or employee may act, under the following circumstances:
(b) When a vehicle is parked or left standing upon a highway in a position so as to obstruct the normal movement of traffic or in a condition so as to create a hazard to other traffic upon the highway.
7'6" is not enough for a fire truck, and unless there are no cars parked on the other side of the road, a fire truck would have a very difficult time squeezing between two parked cars on such a narrow roadway. However, if the area is so constricted the city should have signed the zone for no parking or painted the curbs to indicate the same.
This is not a "no parking area" This has been a parking spot for the thirty years I have lived here. There is one driver who drives up the road as a time when the afternoon sun does make visibility difficult that has ( I have learned from a discussion with neighbors) called on numerous occasions to complain.
The car itself was parked as far from center of road as is possible given that there is a steep slope on right shoulder. I re measured and it seems there is about 7' 6" between side of car and center of double line.
Were your right wheels more than 18" from the curb? Was any part of the vehicle jutting out into the roadway? What kind of vehicle are we talking about?
You have ten days from the time of the impound to schedule a post storage hearing with the impounding agency to discuss the legality of the tow. They have 48 hours (two business days) in which to schedule it.