What is a street fitting?

How did street' originate in the plumbing term street ell?

A "street ell" may have gotten it's name because it describes a 90˚ fitting particularly useful in tight, street ditches. When installing water pipes under a street, or from a water service, again under the street, into a home or business, this street ell allows one to change pipe direction with one less fitting, and in less space, than with a standard ell. A "street ell" may have gotten it's name because it describes a 90˚ fitting particularly useful in tight, street ditches. When installing water pipes under a street, or from a water service, again under the street, into a home or business, this street ell allows one to change pipe direction with one less fitting, and in less space, than with a standard ell.