SAN DIEGO -- An "unknown volume" of raw sewage seeped into Lake Hodges, prompting water officials to place warning signs around the lake Saturday, according to the San Diego water department.

The raw sewage began seeping Friday from an area two miles south of the lake, officials said.

It flowed into a canyon at West Bernardo Avenue and an unknown amount may have reached the lake.

Lake Hodges provides water to the San Dieguito Reservoir, which supplies San Diego with drinking water, city water officials said.

The pumps that move water from the lake to the reservoir were turned off until water samples show the lake meets drinking water standards, the city said.

Signs have been posted around Lake Hodges, warning of possible sewage in the water, city officials said. The signs will remain until the water is safe for recreational use.