Divers are looking in the Chesbro and Uvas reservoirs, both located west of Morgan Hill and in close proximity to LaMar's home. They're searching for any evidence connected with the disappearance of the 15-year-old, including the worst-case scenario of finding her body.
Investigators are following up on more than 1,000 images captured by sonar equipment.
"We are fortunate we have a device that can tell us interesting things, but it can't tell us what those things are, so it's up to us to search that whole area and find a piece of evidence or something that can help us in searching," diver Peter Robinson said.
Two off-road dirt bikes are also searching the trails near the reservoirs.
Dive teams have been able to eliminate four of the five areas of interest at Chesbro Reservoir so far.