The A361, which connects Glastonbury and Street with Taunton and which has been closed for much of the last three months, has reopened today.
The stretch of the road between East Lyng and Burrowbridge was closed in November following heavy rainfall.
It reopened for three days in mid December before closing again after a further downpour.
Somerset County Council says the water level has now fallen to a safe level and the road was reopened after passing an inspection at lunchtime today.The road was shut for four weeks in November as the water level rose and the Environment Agency allowed the surronding land to flood to relieve pressure on other areas.
The road closure left drivers with a 20 mile detour through Bridgwater. Some motorists who ignored the warnning signs found themselves stranded by the floodwater.
Since the closure the agency has been mounting pumping operations that have seen 5 billion gallons of water transferred from the levels into rivers and drains.