The break, which occurred in Richardson according to a news release from the city of Plano, has also affected water supply to Richardson, Garland, Murphy, Sachse and Wylie.
The North Texas Municipal Water District is expected to restore full capacity of the transmission system over a 72 hour period.
Though Plano is not directly affected by the break, it receives water from the same transmission system, according to the news release. The water conservation measures are precautionary.
NTMWD said in a news release that water quality will not be affected.