A voice grade telephone line is needed at the station for voice communication and at stations where the station signals have to be transmitted by telephone to another nearby existing facility which has a radio, a four-wire data circuit (FDDA) is required.

A telephone outlet shall be provided near the interface relay cabinet. A one-inch empty conduit shall be provided from the remote terminal unit cabinet to the telephone backboard at stations with data circuit.

Interfacing with the telephone company shall be done by the consultant. WSSC will order the circuits during the construction phase of the project. The contractor has to coordinate with the telephone company for the cable installation. A touchtone telephone will be provided by the WSSC. (Design Guideline DG-08 § 15.0, dated August 2006)