What, in some places at least, a "Toby" is. Apparently, says t'int'ernt, a "Toby" - in Britain and New Zealand no less - is the valve that sits between the water main and your properties supply pipework. Hence the generic term "Toby Box" for those hatch-lidded openings in the highway, used for water meters, valves, and (pertinent to our village atm) termination of FTTP feeds before being connected to the property itself.
I've never heard the term "Toby" used for a valve. It's apparently from an Irish term for a roadway (the Toby), and short for "Toby-Cock" or "Toby-Valve".