The southbound lanes of Interstate 805 flooded in Otay Mesa because of a nearby water main break.
CHP officials said the water flooded two lanes of the highway near Palm Avenue just north of Interstate 905.
The flooding and closure affected traffic up to Main Street bringing speeds down to 8 mph past the scene.
A nearby collision involving injuries was more than likely caused by the car hitting the water and hydroplaning causing a crash according to a CHP spokesperson.
Water was turned off around 6:55 a.m. helping clear up the traffic backup along the highway.
San Diego City water crews are working alongside Cal American crews to determine the cause of the flooding.
The break is located at the connection of two pipes - one from the City of San Diego, the other from Cal American according to San Diego City spokesperson Arian Collins.
Cal American services San Ysidro, Coronado and Imperial Beach.
Crews will need to excavate the pipes to determine which of the 10-inch pipes needs replaced.
CHP officers were preparing for a long-term closure depends on how fast the repairs can be made.
The only businesses affected were a McDonald's restaurant next to the source of the flooding and a small shopping center located on Palm Avenue just west of I-805.
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