A wet tap connection refers to a connection made into a New York City or public water main for a water service line connection. Usually such a connection is for an individual property. In NYC before the advent of cast iron water main pipes a NYC water main was actually constructed out of wood. They were typically hollowed out tree trunks, frequently with the bark of the tree still left on. The common term ‘fire plug’ refers to a time before fire hydrants.
When a fire erupted the firemen of the day would actually cut a hole into the wooden NYC water main in order to have access to water and attempt to put the fire out. This actually was a step up from a ‘bucket brigade’. At the conclusion of the fire, and the need for water, the opening made for fire department use would be plugged. Hence a ‘fire plug’. A wet connection for a water service line would be installed in like manner.
Wet Tap Connection
The tap, sometimes called a wet tap, is the connection from a main water line to the NYC DEP owned water main usually located in the roadway. If a connection is undersized it will not permit proper water volume to enter a premises no matter how large the water line is. This is even more of an issue in the old Jamaica Water territory that the NYC DEP took over in the 1990’s. A new tap costs around $300.00 which is a small price to pay for ensuring a correct main water line job.
New connections are easily installed by NYC DEP field forces in around 20 minutes after the NYC licensed plumber has secured the proper permits. With the modern tools now in use, installing a tap only results in about a 1/2 gallon of water being lost when a hole for a new connection is drilled into a NYC water main. A wet tap ranges in approved sizes from 3/4″ up to 2″ (a 1/2″ water line connection pictured to the right is not legal for use). If a size larger than a 2″ connection is required, then a ‘wet connection’ would be required.
Driven Tap Connection
That is why these old water service line connections are referred to as driven taps. Unfortunately these frequently undersized connections can become clogged. They also became inadequate as most modern buildings require a greater volume of water due to an increased number of plumbing fixtures. More troubling however is the fact that because they were ‘driven in’, they also frequently blow out without warning.
A driven tap must be handled with extreme care and is never suitable to be re-used when a water line leaks. If a main water line has to be replaced a new tap must be installed using modern tools and be an adequate size.
A wet connection is for a larger sized main water line and is installed in a different manner than a wet tap. A wet connection is for connections whose size exceeds 2″, typically for apartment buildings or when fire sprinkler protection is required. In NYC there is an increasing demand that various types of residential and commercial buildings must have a fire sprinkler system installed.
Unlike a tap connection, which is drilled into the NYC water main, a wet connection is actually a ‘core drill’. This means that instead of drilling the main water line, like someone would drill a piece of wood for instance, a section of the main water line is actually cored drilled out of the City water main. The core drill hole is equivalent in size to the needed connection.
When wet connections are required a specialized NYC DEP crew is utilized. This crew is sometimes still referred to as ‘the caulkers’ in the plumbing trade. The term ‘caulkers’ refers back to the day when lead joint wet connections were installed. These wet connections had their joints sealed with molten lead that were caulked in place. The lead used never came into contact with the water supply as a treated rope called ‘oakum’ actually made the joints water tight. The molten lead was used as a means to keep the ‘oakum’ in place. New wet connections are installed with ‘mechanical joints’ and contain no lead whatsoever.