Specialist officers from Dyfed-Powys Police, along with others from other forces, have been searching the area in and around Machynlleth since the beginning of October.
The force says the search areas identified during the course of the investigation were completed on Friday.
47-year-old Mark Bridger has been charged with murder, abduction and intending to pervert the course of justice.
He denies all the charges.
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Not a bad start to the weekend, bright spells and showers for most of us.
None of the people onboard the boat had been wearing a lifejacket. They were spotted clinging to the hull of their upturned boat.
Staff at seven museums in Wales are taking strike action this weekend over plans to cut their pay.