HANOVER, VA (WWBT) - One of the big focuses of the search for Robert Wood, Jr. has been the North Anna River, including the part close to where Robert was last seen, and areas downstream.
They're back-tracking to locations marked specifically to be re-checked.
They also expanded the search area to nearly four miles from where Robert was last seen five days ago in the North Anna Battlefield Park.
The river is a big focus. Dive teams are traveling downstream looking for clues. Tethered to kayaks, a boat carries a specially trained dog.
The North Anna River level dropped two feet, after Dominion stopped the flow to help divers search for any sign of Robert.
"In most places we can see the bottom, fortunately we have these kayaks we can skim across in about four to six inches of water," said Jeremiah Sheehan, with Hanover Fire.
But other spots are too deep.
"Those areas have been marked, and if need be we can go back with scuba equipment," said Sgt. Lee Elliott with Virginia State Police.
One challenge divers are dealing with is debris from Hurricane Irene. Trees are down over the river so they're having to get out of their kayaks and walk along the banks around it.
"You're having to from points walking down the river with no obstacles to fallen trees, big rocks and little branches, so it's slow going," said Sgt. Elliott.
Volunteers are also covering ground by horseback.
Beth Linton and Shaun Engleby are not trained in search and rescue, but were paired up with people who are.
Their team disappeared into the brush toward the North Anna River where miles of rugged search terrain awaited.
"You never know what the terrain is so they're putting our horses up to a test," said Engleby.
"I just feel like he's a tough little boy playing around out there. The weather hasn't been that bad, he's got to still be out there," said Linton.
Survival packs left for Robert remain untouched, but that won't stop the hundreds determined to find him.
"Our assertion that Robert is still alive has not changed. We will be acting with a sense of urgency 24 hours a day until he's found," said Captain Mike Trice with the Hanover Sheriff's Office.
Authorities remain in constant contact with Robert's family. His mom and dad have taken part in the ground searches.
Plans for Friday volunteers have also been announced:
If you're looking to assist in the search for Robert on Friday, the new meeting location will be at the Meadow Event Park, Gate 9 in Doswell.
If you've already been trained earlier this week, you're asked to arrive at 8:00 a.m. If Friday is your first day volunteering, you're asked to arrive at 9:00 a.m.
Directions to the Meadow Event Park can be found here: http://www.meadoweventpark.com/directions
Police want to thank every single person who is donating their time and energy to help find Robert.