Motorists plying the Kitale-Lodwar road may be able to use the Kainuk bridge by Wednesday, KeNHA said on Tuesday.
The bridge was washed away by floodwaters on Sunday after heavy rains pounded the area paralysing transport through the route.
KeNHA assistant communications officer said Charles Njogu said repairs are on course.
"Reinstatement of the washout commenced and by 2pm on November 7, substantial rock feel and gravel had been undertaken."
"KeNHA is working determinedly to ensure repairs are completed on Wednesday and passage of traffic restored," Njogu said.
On Monday, people travelling from Ludwar to Kitale and those from Kitale to Lodwar were dumping their passengers at the bridge.
Some traders had to incur heavy losses as circumstances forced them to hire people to carry their goods across the river.
Njogu warned those plying the Kitale-Lokichar-Lodwar-Nadapal road to be cautious where approaching the area.
Last month, the roads agency repaired the bridge and said it will be operational to low tonnage traffic.
This was after the highway, which connects Kenya with South Sudan, was shut at the bridge as a safety measure to avert further losses.
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